Author: chogan@directresearch.com

Post #1934: No spare tire? When did this happen?

 

You buy into new tech, you expect certain aspects of your life to change.

Buy a Chevy Bolt, and part of the deal is that you stop saying “gas pedal” for the accelerator.  Likewise, “step on the gas” is no longer a valid request.

I guess I should have seen it coming.  But I now wonder how long it will be before the phrase “spare tire” goes the way of “cigarette lighter socket”.

Flat tire?  Use OnStar

The Chevy Bolt provides absolutely nothing for dealing with a flat tire.  It has taken me a while to get my mind around why they did that.  And no, I don’t think it’s just to sell OnStar services.

Era 1:  Ancient history, the true spare tire.

Standard equipment:  Full-service tire and rim, jack, lug wrench.

Back in the day, cars came with five functional rims, and five full-sized tires.  One of those was the spare tire. If you had a flat you could drive on your spare more-or-less indefinitely.  Because your spare was a real tire.

In most cases, you could use any of the five tires/rims, on front or back, or either side of the car.  This, despite whatever folklore you may have absorbed.  This, per the standard method for “rotating the tires”, according to the experts at Bridgestone tires, among others.  (Directional tires — those that have a forward direction of rotation — are the exception.)

Source:  tirerack.com

Era 2:  The limited-service, compact, or doughnut spare

Standard equipment:  Limited-service tire and rim, jack, lug wrench.

Sometime in the 1980s, car makers began to replace the full-sized spare with a “compact spare”.  This was an era when cars were shrinking, gas mileage was at a premium, and competition from foreign manufacturers was intense.  Credit for the first compact spare apparently goes to Volkswagen (reference).

Initially the compact spare was the mark of the econo-box, but eventually it became the norm.

Today, there are still plenty of cars that come with a full-sized spare tire standard, but these tend to run to be cars meant to have an “off road” look, as well as some top-end sedans.  If you buy your typical mid-size middle-of-the-road vehicle, chances are pretty good it comes with a compact spare.

To be honest, as tires got better over the years, and cars got smaller, I found that the full-sized spare was more of a nuisance than a comfort.  Improvements in manufacturing made tire sidewall “blowouts” a thing of the past.  Steel-belted radials made it far harder to get a flat by picking up a nail in the tread.  And, in general, tires just became a whole lot more reliable.  And the full-sized spare ended up just taking up space.

My wife’s 2005 Prius came with a doughnut spare.  We sneered at the time, but a) we used it several times so far, b) it works fine for getting the car to the tire shop, and c) little did we know what was coming up next.

Era 3:  Tire pump, Fix-a-Flat, and a prayer

Standard equipment:  Tire puncture repair kit.

My wife’s 2021 Prius Prime came with no spare at all.  Instead, Toyota provides a “tire puncture repair kit” which, as far as I can tell, consists of some tire sealant in a pressurized can, an electric air pump, and directions for use.

Prayer is optional but recommended.  And as I am a non-religious person, I tossed in an actual tire plugging kit as backup.

This is now the standard on all Prius models.  You don’t even get a doughnut spare,  In effect, you get a can of Fix-a-Flat, an electric tire pump that fits that can, and roughly 35-step directions for use.  I don’t think we even got a lug wrench or a jack, so there’s literally no way for us to take the tire off the car, unless we buy those tools separately. Edit:  Nope, Toyota hid them in an odd spot.  So, oddly, the car does come with jack and lug wrench, but no spare tire of any sort.  That’s a mixed message, for sure.

(For those unfamiliar with the product, Fix-a-Flat (r) is this pressurized goo that you can squirt into a flat tire, and, if all goes well, and you follow directions, it’ll seal the leak in the tire.  At least long enough for you to get to a service station.)

Era 4:  The Chevy Bolt:  Self-sealing tires and real-time tire pressure monitoring.

Standard equipment:  Nada.

The Chevy Bolt takes this to a new low, or new high, depending on your point of view.  Like the Prius Prime, the Chevy Bolt gives you no way to remove a wheel from the car.  No jack, no tire iron. But in addition, they give you no way to fix a flat, period.

Instead, the car comes with “self-sealing tires”.  Bicyclists familiar with the product “Slime” will grasp the concept.  In effect, they have pre-installed Fix-a-Flat, with the idea being that the goo already inside the tires it should seal holes up to about an eighth of an inch.  It also lets you see the tire pressures in real time, which I think would be handy if you’re trying to get a car with a low tire to a service station.

That’s the theory, anyway.  Plus, you are encouraged to subscribe to OnStar.  (I still haven’t figured out how to shut up the OnStar lady upon startup, so I just keep the volume on the radio turned off.)

I have of course put a 12 volt tire pump in the trunk of the Bolt.  Because, in my experience, “self-sealing” tires are more like slower-leaking tires.  It just takes them longer to go flat than if there were no sealant inside the tire.  So I do want to carry some way to inflate the tire.

But I’m thinking long and hard about buying a jack and lug wrench for it.  Not only is the Bolt a relative dense car — short wheelbase, but weighs more than two tons — it has some weird, non-standard jack points.  And Chevy is pretty cagey about just where, exactly, those jack points are, and what will fit.

Crazy as it sounds, to an old guy, Chevy engineers really don’t want the owners to jack up the car, to remove a tire.  And for once, I might just go along with the plan.

In any case, for this car, at least, I think I understand the lack of doughnut spare.  It’s a small, very heavy car.  (As a result, it has a stiff and sometimes uncomfortable suspension, to take all that weight.)  There wouldn’t be a lot of wheel travel with a doughnut spare.  And I think you’d put your battery down too close to the road to be comfortable.

So, on a Prius, if you hit a pothole with the doughnut spare, you might ding a little sheet metal.  With a Bolt, you’ve got some great big battery modules there on the underside of the car.  And I suspect Chevy was a little hesitant to put just a doughnut spare between those and the road surface.

Conclusion

Having had cars with a full-sized spare, a doughnut spare, and no spare, I think the doughnut spare hits the global optimum.  You really only need something that will give you a few miles of travel, a few times in the life of the car.  Just enough to get you home, or to a tire-repair shop.  Dedicating a full-sized tire and rim to that task is wasteful, and overkill.

But no spare?  I’m not too keen on that.  With the Prius Prime, there really is no place to put a doughnut spare.  So I guess I’ll accept Toyota’s puncture repair kit as a necessary evil.  On the Bolt, I can see why Chevy’s engineers might have wanted to avoid a doughnut spare, owing to a very dense, small car with critical components located in the floor of the vehicle.   I’m still not sure why they’ve gone so far out of their way to make it difficult for the Bolt owner to remove a wheel.

In either case — the Prime or the Bolt — I can definitely imagine a situation where I’d want to take the wheel off the car, to get a tire repaired.  That’s a lot less stress on the vehicle than towing the car, just to get a nail puncture repaired.  And right now, that’s not possible, given what the manufacturer supplies with the car.  Not sure what I’m going to do about it.

But this seems to be the trend.  Just as my kids thought I was kidding when I called the 12V power outlet under the dash the “cigarette lighter socket”, someday, when an old guy refers to somebody’s fat gut as a spare tire, none of the younger people are going to have the faintest idea what he’s talking about.

Addendum:  Notes to self on adding donut spares.

Upon further research, nope, no way I can be comfortable driving a care without a spare tire.  Not when I can remedy the situation for a modest expense.

For the 2021 Prius Prime:  The car actually does have a jack, just stowed in an odd place (in a compartment under the back seat).  By report, the tire puncture repair kit is to be used only as a last resort, as using it will kill the tire pressure sensor and require that to be replaced.  By report, the same donut spare fits all regular Prius models from 2004 to 2022.  But the 2017 and later models use a larger, 17″ rim, compared to the earlier models with a 16″ rim.  Experts say you’re better off getting the proper donut for the vehicle.  The Prime still has no place to put a compact spare, and several drivers report tucking it behind a front seat for long trips.  But all we need to do is pick up a donut spare from a junkyard, for any standard Prius model in that range of years,.

For the 2020 Bolt, I’ve already ordered a Chevy S10 jack, from a model year that has the right “button” top jack plate to fit the jack points on the Bolt.  Rumor has it that a Chevy Cruze (2010-2019, excluding diesels!) donut spare will fit the Bolt, with its odd 5/105 bolt pattern.  (The Cruze diesel had slightly larger wheels with a 5/115 bolt pattern).  Everyone says that, owing to the radically smaller diameter of the compact spare (compared to the normal wheel and tire), the compact spare should not be used to replace the front tires (but instead, tires should be shuffled as needed so that a compact spare is used on the rear, in the event of a flat).  The Bolt actually has a wheel well designed to hold a compact spare, but Chevy blocked off part of it, and a spare will only fit completely if stored deflated. 

The upshot is that we’re shopping our local junkyards and/or Ebay for his-‘n’-hers used donut spares, so that when we have a flat, we have some option other than getting towed.

Addendum to Addendum:  I bought some donuts.

Last night I bought what I hope are the relevant donut spare tires off Ebay, having already Ebay’ed a jack/lug wrench for a Chevy S10, to fit the Bolt.  This was more expensive than scrounging the junkyards, but far less expensive than buying a generic boutique “spare nouveu” off Amazon.

The deciding factors in going with the internet were age and fit.  I wanted tires in good shape, because tires degrade over time.  (I didn’t want to buy a donut and immediately have to replace the tire.)  And for the Prius, the rim fit was fairly important.  I only wanted a donut from the latest Prius models, not earlier ones, which means fewer wrecks in the junkyard.

Really, it was like anything else — these days, you get a better selection off the internet than you do in person.  You just pay for it.  When all was said and done, I figured I had a better chance of success picking among 20 or 30 current offerings for each donut on Ebay, than I did driving out to my nearest you-pick junkyard and managing to find exactly what I was after.

On balance, it’s probably a little bit wasteful to carry around that donut spare, when both manufacturers say you don’t need it.  Mostly.  But in the end, I realized the internal inconsistency of stocking a car with disaster preparedness supplies (Post #1628), and then not having any functioning spare.  So I spent a bit of money to fix that.

Case closed.

Post #1933: A short, simple explanation of U.S. immigration law

 

/s.  The title is sarcasm.  This post isn’t about explaining U.S. immigration policy.  It’s about giving up trying to understand it, let alone explain it.

U.S. immigration policy is a stew cooked from ancient and modern quotas, agribusiness needs, humanitarian concerns, special exceptions, vestigial ethnic, racial, and religious bias, aftermath-of-war, left-over anti-communism, workforce shortages, national security issues …you name it.

It’s a dish where everybody gets to toss in an ingredient.  Or maybe everybody who can pay to play gets to.  It’s hard to tell.

Policy consists of turning a blind eye to the results, until it’s politically expedient to do otherwise.

 

And by “blind eye”, I don’t mean merely pretending that those folks don’t exist.  Although there’s plenty of that.

It’s knowing they are there, and dismissing it with a shrug.  Ever wonder why they don’t just impose stiff fines on the businesses who hire illegal aliens?  I mean, putting all the right-wing nonsense aside, if nobody would hire you, there wouldn’t be much incentive to immigrate here illegally, would there?

Ponder this:  About 44% of paid U.S. crop workers are illegal aliens.

Who says so, and how do they know?  Who says that so many agribusinesses engage in such a gross violation of Federal law?  The Federal government does.  That’s straight out of the U.S. Department of Labor, National Agricultural Workers Survey.  (From their 2019-2020 survey results summary, available as a .pdf at this link.)  And that’s the percent of folks who were willing to be interviewed, and willing to admit that they lacked legal status to work in the U.S.   But that’s after excluding all workers under H-2A temporary agricultural worker visas, from the sampling frame, to begin with.)

So it’s not as if this is some unknown, unquantifiable practice.  It’s an integral part of the U.S. food supply.  It continues because in normal times, nobody is quite crazy enough to try to disrupt that without having something else ready to take its place.

Which, needless to say, we ain’t got.

For the past few decades, the “politically expedient to do otherwise” periods seem to occur just after peaks in immigration.

And since we’re having a peak now, you’d expect another round of doing something about it. Beyond the billion or two we’ve been spending each year,  now, to fix the worst holes in the Mexican border.

And so, I finally arrive at the cause of this particular screed.

By report, a large majority of U.S. Senators are on board with beefing up security at the Mexican border.  Among other things.

But it sure looks like nothing will happen, because the Republican candidate for President sees it as too good a political issue to allow it to be solved on somebody else’s watch (reference).  And as an added bonus, we can make Putin happy by hanging Ukraine out to dry.  As part of our non-action on this issue.  And the Governor of Texas can defy the U.S. Supreme Court, with impunity.  Ah, that’s an overstatement, but it’s close enough.  Narrowlly construed, I think the Court ruling merely means that the Border Patrol can continue to remove the razor wire that gets in the way of them doing their jobs,  even as the Texas National Guard continues to lay more razor wire.  Not because it makes sense, or is effective.  But because that’s unbeatable political theater.

This is U.S. immigration policy?  Yep, it’s what passes for it, in the current situation.

Define U.S. immigration policy?  Apparently, it’s whatever the Republican executives want it to be.  Nothing more and nothing less.

Maybe I see the past through rose-colored glasses.  Maybe it’s because I spent a decade working for a U.S. legislative-branch agency, and ended up with a lot of respect for then- members of Congress.  But I swear that the U.S. Congress didn’t used to be anywhere near this screwed up.

Post #1932: The death of my electric vehicle has been greatly exaggerated.

 

I bought a 2020 Chevy Bolt about two weeks back. It’s an electric vehicle with a roughly 250-mile range.  I did my research. Waited for prices to drop.  Got a pretty good deal on a low-mileage car. I think.  Post #1924 summarizes that.

Post #1924: I bought a Chevy Bolt.

And wouldn’t you know it, the very next week the news was full of horror stories about what a bad idea EVs are, owing to poor performance in the cold.  Long lines at public chargers, people being stranded, people getting towed.  The whole nine yards.  This, accompanied by the usual sneering comments from John Q Public.

OMG, did I just make a huge mistake? Continue reading Post #1932: The death of my electric vehicle has been greatly exaggerated.

Post #1931: Custom oil candle base for the Luminiser TEG lantern

 

This is the third (and, I hope, last) in a series of posts about the Luminiser thermo-electric-generator lantern.  This device makes light by converting the heat of a candle to electricity, then using that electricity to run some LEDs.

The claimed output of the Luminser is 200 lumens, or about one-quarter as bright as a “60 watt” light bulb.  It’s an impressive piece of technology for $20, and an impressive amount of light from the heat of a single tea-light-sized candle.

But it has a couple of problems.  It’s not very stable (sitting on four spindly plastic legs, as shown above), and it uses a disposable, proprietary oil candle as the preferred power source.

I happened to notice that the base of the Luminiser lantern is almost exactly the same size as a U.S. standard wide-mouth canning jar.  Which then immediately suggested a solution.

I’ve now fixed both of those issues by converting a standard wide-mouth mason jar into a custom oil candle, just the right size to be used to stabilize and power this lantern.  My Luminiser now rests securely on the mason jar, with the candle flame at the same height, and of the same size, to replace their proprietary disposable oil candle.

Here’s the final product, below, where I’ve removed the flimsy plastic legs, and used a low-profile pint (500 ml) canning jar as the base.  Plenty of light to work a crossword puzzle with no eyestrain.  All that, powered by a flame about the size of what you’d get from a tea light candle.

Directions in brief

Overview

Start with a wide-mouth canning jar (mason jar, Ball jar), pint or half-pint size.  Drill a little hole through the metal lid.  Stick a little piece of copper tubing through that.  Run a piece of cotton kitchen twine through that tube, to form the wick.  Fill the jar with lamp oil, screw on the lid, and that’s your oil candle.

(N.B., canning jars come in two formats in the in the U.S., regular and wide-mouth.  Wide-mouth is the right choice here, as that fits nicely into the base of the Luminiser.)

That’s the finished oil candle, shown above.  This now fits neatly against the bottom of the Luminiser, and replaces the proprietary oil candle.

NOTE:  You must also drill a small pressure-relief hole in the lid in order to use this safely.  That’s really the only part of this that isn’t obvious.  That little pressure-relief hole is a standard safety feature on oil lamps.  It is important that you include it in this oil lamp.  Even if you skip all the rest of the directions, read that part, in red, below.

Materials:
  • Pint or half-pint wide-mouth canning jar, with band and lid (a.k.a., two-piece metal lid).  If you’ve read this far, I probably don’t have to tell you, but don’t use a plastic lid.
  • 1/8″ rigid copper tubing (sold in 1′ pieces at ACE Hardware, $2, reference below).
  • A foot or so of cotton twine, ~2.5 mm diameter, sometimes sold as  “butcher twine” (the stuff you’d use to “truss a chicken”, see below for brief discussion).
  • For attaching the copper tubing to the lid:
    • A few drops of superglue  OR
    • Optional:  A small amount of two-part epoxy OR
    • Crazy optional:  Torch and solder.

Tools:

  • Razor-blade knife (Skil knife) or single-edge razor blade.
  • A bit of sandpaper.
  • Drill, with bits:
    • 1/8″ drill bit (to drill hole in lid for wick-holder tubing)
    • 1/32″ (or tiny) drill bit (to drill air relief hole in lid).
  • Metal paper clip (to push cotton twine wick through the copper tubing).

Part reference:  The only “exotic” piece of material here is the thin copper tubing.  My local ACE Hardware sells that, shelved with hobby supplies, for $2 each.  It’s “K&S 1/8 in. D X 1 ft. L Utility Copper Tubing“.  The metal does not make any difference — copper, brass, or aluminum would all be fine.  But the dimension is fairly critical.  Don’t go larger, you’ll get too big a flame.

Cotton twine:  The cotton twine needs to be small enough to fit through the copper tube, but must fit snugly inside the copper tube.  The theoretical internal diameter of that 1/8″ O.D. copper tube is .105″ or 2.667 mm.

You may have to eyeball this, as it’s hard to find twine marked as to diameter, or even as to twine gauge, in the hardware store. Ideally, the cotton twine would run about 3/32″ or 2.5 mm in diameter when lightly twisted.  The twine I used was not quite as thick as two U.S. dimes, as shown in the pictures below, thicknesses in millimeters.

What will work:  You want 2.5-ish mm cotton twine.  Of what I saw on the shelf at my local ACE Hardware recently, this product, labeled butcher’s twine, looked about right.

What might work, but I haven’t tried it:  In theory, purpose-made 2.6mm oil candle wicking on Amazon should work, but I can’t say that I’ve tried it, and it’s expensive.  If it works, it’ll be a tight squeeze.  Separately, a lot of cotton kitchen twine, package-wrapping twine, and general-purpose twine will be too small unless you double it or triple it up before feeding it through the copper pipe.

What won’t work:  Material sold as 1/8″ round oil lamp wicking is way too large for this use.  Any twine or wicking sold as 3 mm or larger is too large.  Wicking or twine sold as 2 mm or smaller would likely be too small.  Anything with a “twine gauge” or “size number” in the 10s or 20s (e.g., #12 twine) will be much too small unless you double it up or triple it up.

Finally, you can’t (or, at least, shouldn’t) use twine made of synthetic materials for this purpose,  Whether you could use other natural materials (e.g, jute), I have no idea.

Directions in some detail.

1:  Prepare the wick holder.

Cut 1.5″ off one end of the copper tube.  The simplest way to do this is to place it on a flat surface, place the Skil knife blade or single-edge razor blade on top, and roll it back and forth until the knife edge cuts through the thin copper tubing.  Remove the burr around the cut edge by sticking the paperclip in and working it around until you’ve opened cut end back up to the full diameter of the original copper tube.

2:  Prepare the wicking.

Cut a foot or two off the roll of cotton twine. 

Thread the cotton twine through the 1.5″ piece of copper tubing.  First, bind one end of the twine using superglue.  Hold the tightly-twisted cotton twine in one hand, put a few drops of superglue near the end, and let it set up.  Once set, snip off the little bit of twine past the super-glued part.  If you did it right, you end up with a nice, tight, rigid section of super-glued twine that you can then poke into the copper tubing.  (Same concept as an aglet, or shoelace-end.)  Once you have that started, use the paperclip to push it all the way through.

3:  Prepare the metal canning lid.

Sand the plastic coating off a square inch or so of the interior of the lid, right at the center.  This is to help whatever glue/solder you use to stick the wick holder to the lid.

Drill a 1/8″ hole in the center of the lid.  Wallow it out just a bit.  Sand it to remove any burrs.

Drill a tiny hole (1/32″ or so, smaller is better) well off-center, but not covered by the screw-on band that holds the lid in place, to provide air pressure relief.  You must provide this pressure-relief hole in order to operate this safely.  If you do not do this, and you screw the lid on tight, the oil candle will enter “runaway” mode when you use it.  Oil and air expand as they warm up.  If you do not provide a pressure relief hole, that will force oil up and out of the wick, resulting in an ever-increasing flame, and possible fuel spill beyond the top of the candle, and a fire.

This tiny vent hole is a standard safety feature on oil lamps, it’s just typically placed so that you don’t notice it on store-bought oil lamps.  You may see directions for mason-jar oil candles, or even commercially-offered mason-jar oil candles, that skip this step.  The resulting products are decorative objects, not working oil lamps.  If you actually want to burn this candle safely, include the air vent, just like a real oil lamp.  You may think to yourself, oh, I’ll always remember to leave the lid a bit loose, or some such.  But at some point, either you or somebody else will forget to do that.  Do your future self a favor and drill that pressure relief hole when you drill the main 1/8″ hole for the wick holder.

4:  Assemble.

Poke the copper tube through the lid, so that the long “tail” of wicking is on the under-side of the lid.

Adjust the copper tube until the top of the copper tube protrudes 15/16″ from the top of the lid.  This adjustment puts the flame in the correct position.  Take the time to get this right.

Super-glue the copper tube in place, front and back, and allow to set.  (This is not great technique, but it’s fast, and it mostly works.  A more secure method would apply a small amount of two-part epoxy to the back of the lid, around the tube.  Or would use a torch and solder to affix the copper tube to the metal jar lid).

Cut the bound end off the cotton twine/wicking, and adjust the cotton twine so that it barely protrudes beyond the end of the copper tube, about 1/16″ to 3/32″ or so.  Something under 1/8″.  This small amount of exposed wicking will generate a flame that’s the right size.  If you leave too much exposed, you will get an unusably large flame, and you’ll have to go back and adjust the wick once it’s wet with lamp oil.  You want just a tiny bit of exposed wick.

5:  Fill, light, test.

Add lamp oil.  To reduce the total amount of oil present, you may want to put some heavy inert filler in the jar, such as marbles, glass weights, clean rocks, or similar.  DO NOT OVERFILL.  As with any oil lamp, leave space at the top of the jar, to allow for easy expansion of the oil as it heats up.  A good rule-of-thumb from canning is, when in doubt, allow a 1″ headspace.  Don’t fill it closer than 1″ from the rim.

Insert the tail of the wick in the oil, put the lid on top of the jar, screw the band on to hold the lid into place.

Wait a few minutes for the lamp oil to saturate the wick.

Light and observe.  You want a flame that’s maybe 3/4″ tall.  Let it burn for 10 minutes to be sure that the flame height remains steady.

Note that the top of the tube is just shy of 1″ above the metal canning lid, and the flame is under 3/4″ tall.

Place the Luminiser over the mason-jar candle and observe another ten minutes to make sure the flame height remains steady.

Below is the final version, using a shorter jar, with the folding legs removed.  To remove the legs, take a Skil knife (utility knife) and slice the inside “rim” off the split plastic pegs that hold the legs on.  You can then pull those plastic pegs out of holes that hold them to the body of the lantern.  Toss the flimsy plastic legs, as they will no longer stay attached to the lantern after you do this.

Never leave the lit Luminiser unattended.

6:  Main drawback:  Awkward wick adjustment.

A simple oil candle like this lacks the “wick riser” mechanism of a real oil lamp.  (That’s the little wheel that you turn to raise or lower the flame.)  For this oil candle, you have to adjust the wick height by tugging on the wick and/or pushing on the wick.

As long as you don’t let the wick burn down to a nub, you should be able to grab it with pliers (or maybe even large tweezers) and give it a little tiny pull to lengthen it.

If you overdo that adjustment, you can either stuff the wick back down the tube, using a paperclip, or you can take the top off the jar and pull the wick back down.  If you let the wick it burn too far, so you can’t grab it from the top, you have to take the top off and use a paperclip to push the wick up.

It works, but it’s awkward.  Luckily, you don’t have to adjust the wick often, once you achieve the right flame height.

If it weren’t for the fact that a wide-mouth mason jar works so well as a stable base for the lantern, I’d probably have bought a commercial lamp mechanism for a mini-oil-lamp, and worked from there.  Just to get an easily-adjustable wick.  As it stands, the awkward wick adjustment is a minor annoyance I can live with.

7:  Eventually, deal with the lantern legs.

The pieces of perforated black plastic in the photo above are the flimsy lantern legs, folded up.  At some point, I’ll either remove them, or cut them so that they will fit over the final (likely, half-pint) container, and so hold the lantern firmly to the mason-jar base.

It works fine as-is.  Its mostly that those folded-up legs spoil view a bit.  Fixing that is optional.

Edit:  Done.

Conclusion

The end result is a heavy, solid base for the Luminiser lantern, along with an oil candle that could hold a several-week-supply of lamp oil.  This avoids the relative unsteadiness of the original design, and allows you to fuel the lantern cleanly without using the proprietary disposable oil candles sold by the manufacturer.

The fit between the standard wide-mouth mason jar and the Luminiser is so good that it almost looks as if this were made for it.   It’s like having an oil lamp with a chimney.  Except that the chimney puts out twenty times as much light as the oil lamp itself.

Replacing the pint wide-mouth mason jar with a half-pint would make this more stable, and more difficult to knock over.  (The only reason I made this with a pint is that I didn’t have a wide-mouth half-pint available.  I plan to replace my pint jar as soon as I can lay hands on a half-pint.) Edit:  I have now replaced it with an even better choice, a low-profile pint jar, as pictured near the start of the post).  If you desire stability beyond that, epoxy the mason jar to a suitable base, such as a piece of marble or wood.

Finally, let me emphasize the general safety precautions.  Don’t run this unattended.  Don’t run it with a flame bigger than about 3/4″.  (If the flame is too big, pull or push the wick down further into the tube.)  Drill that tiny pressure relief hole before you use this, to avoid a runaway lamp situation.  For indoor use, burn only lamp oil or kerosene (e.g.,”Klean Heat”).

That said, you do this at your own risk.  This is, after all, quite a bit of easily flammable material, all in one place.  As with any candle or oil lamp, you always need to keep in mind that you are playing with fire.  There is an inherent risk in doing that, and to do it safely, you need to acknowledge that, and take all reasonable precautions.

Post #1930: Luminiser lantern, much cheaper to run than a flashlight using disposable batteries.

Above, the Luminiser lantern being powered by a candle (left), and that candle alone, right.

In my just-prior post, I worked out the basic efficiency numbers for the Luminiser candle-powered electric lantern.  It’s vastly more efficient than, say, a mantle-based oil lamp, such as an Aladdin (r) lamp.

I was so struck by how well the thing worked …

Scratch that.  I was so struck that the thing worked, at all, that I neglected to show any numbers on  operating costs.  Let me fix that now.

If you are “on the grid”, nothing is as cheap as plugging an LED lamp into the wall.  No surprise there.  Not by a longshot.

But suppose that, as a moral issue, you would not allow the general use of electricity in your home.  You live in a home that is not merely “off the grid”, but one that is purposefully and thoughtfully un-electrified. For the sake of argument, let’s say you would selectively allow battery-powered devices, when useful and necessary.  A flashlight, for example, might be OK, but a battery-powered television would not.  But you had to use disposable (alkaline) batteries, for such devices, because there’s no place to charge your rechargeable batteries.

That’s all by way of setting up the comparison.  How would the operating cost of this candle-powered lantern stack up against that of a standard battery-operated lantern or flashlight using cheap, disposable AA alkaline batteries?

Turns out, depending on what you burn in your Luminiser, it’s either vastly cheaper or merely a lot cheaper, than producing the same amount of light with disposable AAs.

I didn’t expect that, and I find it kind of interesting.   Despite the seemingly Rube Goldberg nature of this device — you use the heat of a little oil lamp (“oil candle”) to run a thermo-electric generator, to power some LEDs — the running cost of this is vastly lower than using disposable AAs in a flashlight.

Here are the results of my cost calculation.  Assuming I haven’t slipped a decimal point somewhere, the Luminiser powered with ordinary gas-pump K1 kerosene costs about 3% as much to run as a battery-operated lantern powered with disposable batteries.

Description of the calculation follows.

A few key details

This calculation assumes the following prices, current as of January 2024:

  • 33 cents per AA battery, based on a box of 60 currently at Home Depot.
  • $5/gallon for K1 kerosene (roughly the U.S. national average right now).
  • $15/gallon for Kleen Heet deodorized kerosene (Home Depot price).
  • $30/gallon for paraffin oil (the finest fuel for flat-wick oil lamps), based on the current ACE Hardware price.

For the output of the Luminiser, I’m just accepting the manufacturer’s specs of 200 lumens, for 8 hours, using one 44 milliliter oil candle.

The only hard-to-pin-down unknown is how many lumen-hours you can squeeze out of the typical disposable alkaline AA battery.   This is hard to pin down from manufacturers’ published data for many reasons, not the least of which is that they’ll lie.  But in addition, modern flashlights contain circuits that will turn down the brightness if they are left on.  And, they’ll get dimmer as they run, in any case.  Manufacturers tend to publish data on maximum brightness, and then on run time, where (unstated) the run time is mostly at some much lower brightness.  This means you can’t just multiply published lumen numbers by published run time numbers.  That will typically vastly overstate actual light output.

In my post on candles and lanterns I used an example of a real-life device that produced about 300 lumen-hours per AA battery.  That was a marine distress signal, and likely had been optimized for long battery life.  Similarly, this Nitecore flashlight works out to about 250 lumen-hours per AA battery, on low.

The figure of 300 lumen-hours for a typical AA alkaline battery is consistent with a typical AA alkaline battery capacity of 3 watt-hours of energy, and an overall energy efficiency of LED/driver circuit of 100 lumens per watt.  The AA alkaline capacity figure is pretty much a known, and the lumens-per-watt figure is at the high end of the current crop of off-the-shelf hardware-store lights.  (E.g., 90 lumens per watt for these LED bulbs (Home Depot reference).

Close enough for this kind of calculation.

Addendum:  Re-using/replacing the oil candle.

Edit 1/22/2024:  One day later, and this is obsolete.  See next post for making the permanent refillable replacement for these.

Above:  Original oil candle, 3/16 twist drill, glue syringe, and tiny drill (for air hole).

Below:  Luminiser burning with factory-original candle, and with refilled candle.

The key to operating this cheaply is to use some sort of re-fillable oil lamp to power it.  As shipped, the device comes with a small disposable oil lamp (“oil candle”).  That’s engineered to work correctly with this device, but is an expensive way to produce light.  To run it cheaply, you need to a way to use off-the-shelf kerosene or lamp oil to power this.

I did the obvious thing and demonstrated that I can, in fact, refill the little disposable oil lamp that comes with the light.  At least once.  Drill a hole just big enough for a glue syringe, drill a second smaller hole for to release air, fill the syringe with lamp oil, and inject in into the oil candle.

That works fine.    Light might be a touch dimmer, consistent with using lamp oil (paraffin oil) for the refill, which by reputation will not burn as hot as kerosene.  But if it is dimmer, it’s not dimmer enough to matter.

Lamp oil and kerosene have high flash points, so I’m not terribly worried about the little open holes in the shoulder of the oil candle.  Other than as a spill risk.  Pretty sure the plastic enclosure (and the plastic oil candle itself) would melt before it got hot enough to flash over the raw lamp oil.

But the wick on these disposable “oil candles” does not appear to be adjustable.  Or, at least, not without a lot of effort.  So this looks like it may work once or twice, but not indefinitely.

In the long run, I’m probably going to adapt one of my small (night-light-sized) oil lamps for this purpose.  These lamps are just a few inches tall, and take a round cotton-cord wick instead of a traditional flat oil-lamp wick.  They can produce a flame that’s about the size of the flame produced by this oil candle.  So, by inference, they should be just about exactly hot enough to run this device as the oil candle does.

The Luminiser seems like a robust device, in terms of fuel source.  People have run it successfully using a variety of setups for candles, for example.  Separately, I got it to run by simply sitting it on top of the chimney of one of those miniature oil lamps.  It’s no surprise that refilling the disposable oil candle with lamp oil works well. 

At this point, I’m sure I can find a setup that is both convenient and works well.  But I need to work up something a little more permanent, and a little less hazardous, than any of these makeshift solutions.  I should probably also muck about with the electrical side a bit.  For example, see if I could I gin up a USB charger circuit, and splice it into this.  But that’s for another day.

I’m not usually one to fawn over technology.  But I am reminded of Arthur C Clarke’s dictum:  Any sufficiently advanced technology is indistinguishable from magic.  I mean, I know how it works — as discussed in the last post, it’s a TEG.  But at a gut level, you feed this gizmo a little tiny candle flame, and it spits out enough light to read by.  Not magic, but it sure looks like it.

Post #1929: The caveman wants his fire, or, better to light one candle.

 

I just bought a candle-powered electric light, on Amazon.  The Luminiser, for $20.

What attracted me to this device, aside from the low price, is that it seems like such an irredeemably stupid concept.  Perfect for the headlights on your horse-drawn EV.  Or perhaps to replace the light bulb inside your ice-powered electric fridge.

It’s almost as if some nerds took steampunk literally, glommed up a bunch of money via Kickstarter, and created this pseudo-retro-techno-thing.  Which is, in fact, how this was developed.

But all that aside, a) it works like a charm, b) the underlying tech is pretty interesting and mostly, c) it’s a vastly more efficient light source than the candle that drives it.  And d), I’ve been wanting to own a device of this type for quite some time.

In fact, in terms of in-the-home, fossil-fuel-fired lighting — oil lamps, candles, Coleman lanterns, Aladdin lamps, gas-mantle lamps, and all of that — this is by far the most efficient one you can buy.

So chalk one up for steampunk, as I sit here typing by the light of that lantern, warmed ever-so-slightly by the candle flame in its heart.

In any case, I’m going to use this new toy as my excuse for running the numbers on the entire range of lighting — from candles to LED lights — that I have in my home.

But I’m leaving the deeper moral question for another day.  Would the Amish accept this?  At root, this two-step light generation process is no different from a mantle-type oil lamp, which is a technology generally acceptable to the Amish.

Continue reading Post #1929: The caveman wants his fire, or, better to light one candle.

Post #1928: Will those who succeeded in immigrating illegally please raise your hands, part II

 

In the prior post I established some basic facts.

1:  We’re still running somewhere around 2M unsuccessful attempts at illegal immigration, per year, at the Mexican border.  This is about a third higher than the previous peaks in FY 1986 (1.6M, Reagan) and FY 2000 (1.6M, Clinton).

Source:  Ultimately, the data are from US DHS, but read the prior post to see what I had to do to generate a consistent timeseries, including COVID-based expulsions,.

2: There are no hard numbers on the count of successful attempts at illegal immigration, per year, at the Mexican border.  That’s the subject of this post.  How do they estimate the number of illegal immigrants successfully crossing the Mexican border?

3:  The Congress has been funding increased personnel, barriers, and tracking technology at this border for decades, and continues to do so today.  That includes 1986 legislation that doubled the size of border patrol staff, and 2006 legislation that authorized 700 miles of walls/fences.  In recent years, the Congress has been funding “border barrier construction” at the rate of about $1.5B/year.  I believe this funding is what Biden administration is using to patch a few of the worst known holes in the Mexican border, in Arizona.

Source:  DHS Border Barrier Funding, Updated January 29, 2020, Congressional Research Service
https://crsreports.congress.gov, R45888   NOTE that there’s a large pot of money not under the control of DHHS that is not accounted for in the recent-year data.  As of this writing, I don’t know what that’s being used for.

I recommend that CRS report, cited just above, because you can see how rational the border control strategy was, at least historically.  To nobody’s surprise, they called in experts from the DoD, and they focused the resources on the easiest/busiest illegal entry routes first (CRS report, op cit, page 2).

That $1.5B a year is in addition to the roughly $6B one-time transfer within the Department of Defense budget, attempted by then-President Trump, to various border security projects.  Of which, only about $2.1B in total is available to be spent, the rest being tied up due to the (ahem) unorthodox way in which the funds were allocated, in part, via a declaration of a National Emergency. (This, as of the 2019 CRS report cited below.)

If you want to know what the DoD has been up to, with the monies re-allocated via declaration of National Emergency, there’s a corresponding CRS report on that, as of 2019, but I couldn’t quite make out what has actually taken place under that funding (reference available on this web page).  Near as I can tell, at the time that report was written, seven sections of border fence/wall were were agreed-upon to be built under DoD funding authority. But it’s clear that funding it this way created a lot of legal and other messes, some of which have resulted in the majority of funds not being spendable for border security.

Efforts by DHS to Estimate Southwest Border Security between Ports of Entry

Rather than re-invent the wheel and do my own research, I’m just going to summarize a 2017 report by the US DHS, with the title shown above (reference).  This is, in effect, a report by the Government, on the performance of the Government, so it’s not clear whether there are any explicit or implicit biases in the analysis.   If nothing else, it’s probably about as good a summary of the technical problem as you are likely to find.

This is a report done at the behest of the Congress, given the attention that then-President Trump was focusing on the Mexican border.  As described in the Report:

Congress has directed the Department to provide more detailed reporting on southwest border security. The Consolidated Appropriations Act, 2017 directs the Department to publish “metrics developed to measure the effectiveness of security between the ports of entry, including the methodology and data supporting the resulting measures."

To paraphrase, how good a job are you doing now, at preventing illegal immigration across that border, and how do you estimate that?

So this report is exactly what I’m looking for.

Total interdiction rate, including those who turn back after crossing the border:  Implied successful illegal immigration rate of about 30% per attempt.

 

The report spends a of time talking about deterrence.  That is, the people who don’t even try to cross illegally, because we’ve made it tough for them to do so.  Or who turn back, once they see US DHS personnel.  And similar.

For example, US Border Patrol (USBP) personnel count “turn-backs”, that is, estimates of the number of persons who cross the border into the U.S., but turn back and return to Mexico once they spot USBP personnel there.

The USBP also counts “got aways”, that is, individuals observed to have made it past border security.  Essentially, these are reported either by direct observation, or by noticing signs of passage and inferring the number of people involved.

From such counts, plus apprehensions, US DHS calculates a couple of “interdiction rates”, that is, the fraction of all persons attempting to cross, who get successfully turned back.  One of those rates relies solely on data that U.S. DHS personnel observe, and so excludes most of the successful illegal immigrants.  A second estimate of the interdiction rate includes some estimate of illegal immigrants who managed to evade US DHS.

In round numbers, by the end of the period, the US DHS estimate for the success rate at crossing the Mexican border is 30%.  The other 70% either turned back voluntarily when they spotted USBP, or they were caught.

(Note that you CANNOT multiply 30%, times the roughly 2 million illegal immigrants caught at the border each year, to estimate the number of illegal immigrants at about 600K per year.  That’s because the TIR above also includes a count of “turn backs”, who are persons who were NOT apprehended crossing the border.  Based on the above, the estimated number of illegal immigrants has to be higher than that.)

But that depends critically on the very last factor above — the estimated (successful) illegal entries.

How do they estimate that?

Survey data, including only apprehensions (not turn-backs), implied successful crossing rate 50% to 70% per attempt.

There are several long-running surveys of migrants where they ask how often they’ve tried to cross into the U.S., and how frequently they’ve gotten caught.  I cannot even imagine what the potential sampling bias issues are for such surveys.  All I can say is that this DHS report summarizes the results of three long-running academically-sponsored surveys as shown above:  Roughly a 30% to 50% chance of being apprehended on any on attempt at border crossing.

So those who were willing to be surveyed — on either side of the border — report getting caught a lot less frequently than the US DHS “TIR” methodology would suggest.

near-border Repeat offenders, the partial apprehension rate:  Implied successful illegal crossing rate of perhaps 50%.

A final method used by US DHS is to track people who were caught and released into Mexico. Guess how many are likely to try it again.  Then see how many they catch a second time.

Once caught, they record “biometric” information, which I guess is fingerprints, face scans, and similar.  (So that they know if they catch them again.)

They restrict their analysis solely to individuals who live near the border.

Using a survey-based estimate, they take a guess at the fraction of those folks who are likely to try to enter illegally again.

And then they count the number that they catch a second time.

That yields the Partial Apprehension Rate shown above.  Admittedly, these are folks who by definition have had some practice at crossing.  But also, by definition, weren’t particularly good at it.  So, FWIW, they estimate that about half of that population successfully immigrates illegally across the Mexican border, on their second attempt.  And they take that estimate — roughly 50% — as a reasonable guess for the overall rate of successful illegal immigration.

Conclusion

I could go on.  This report presents its own complex estimate of likely count of illegal immigrants, but I honestly didn’t follow the logic or the resulting numbers.

The only real bottom line is that the Mexican border is quite porous, and that successful illegal immigration occurs routinely.  You could quibble over just how large a fraction, but as a good working estimate, you’d be justified in guessing that about half the people who try it succeed.

Moreover, there’s no strong trend there.  The is maybe a little harder to cross now, compared to (say) 20 years ago.  But only a little.

We’re currently targeting a billion or two a year at building and reconstructing walls and fences along the border, adding other security measures, and so on.  I’m hardly an expert, but I’m not seeing anything on the plate right now that hasn’t been there for the past couple of decades.

In any case, given the history of this, I think the notion that we’re somehow going to seal that border air-tight strikes me as somewhat far-fetched. Or expensive beyond our willingness to pay, take your pick.

My prediction is that the current Congress — if it can be prodded into action — will do what prior Congresses have done.  Address the worst known points for illegal entry.  Place a few more patches on the existing system.  And wait for the problem to go away for another decade or so.

No matter how you slice it, the influx of a million destitute people a year, in those border states, has to be putting a strain on something.

Despite the rhetoric, some Federal money goes to support whatever-it-is that communities in border states have to spend more money on, in response.  And while illegal (undocumented) immigrants (migrants) are not eligible for (e.g.) Medicaid, the Feds do, in fact, give communities money to deal with the basic humanitarian issues of food and shelter.  (E.g., $290M, per this press release).  Allocated like so, to local charities in those states, showing just the first few listed alphabetically:

But if you read the fine print, none of that applies to successful illegal immigrants, those who got across the border without being apprehended.  Or are not claiming asylum.  And so on.  Those grants to local charities only apply to those who have been “processed” in some form, by immigration authorities.

So at present, there’s a large influx of very poor people, who are almost by definition outside of “the system” and are categorically ineligible for any type of direct Federal assistance.  For example, they can’t get food stamps (reference).  They are, effectively, un-people.

The only major exception is for children.  Even if their parents crossed the border illegally, in theory, the U.S. won’t allow them to starve.  I think.  And schools that take Federal funds have to enroll them.  I think.  Including free and reduced price lunches, if they are not too scared to apply for that.

And so, we have this weird situation in those border states.  Everybody with any sense realizes they’re getting a million or so people a year, currently mostly refugees from bad conditions in South and Central America.  Or just looking for a better life.  Who crossed the border illegally.  And it’s a fantasy to expect that to stop any time soon.  If ever.  But the Feds can’t do anything to ease the resulting strain on state and local governments, because that large population falls entirely outside of the law.

Everybody knows they’re there, somewhere.  Everybody can see that more are coming.  But nobody can help state and local governments deal with the bulk of the problem.  Because that million-a-year influx consists of people who have no legal standing.  And so we carry on, with policy-by-fantasy, or policy-by-turning-a-blind-eye.  Or no policy at all.

Addendum:  Gross versus net, or missing the reverse flow.

Source:  Immigrationpolicy.org

Notice anything odd about the graph above?  If there’s this huge ongoing influx of illegal immigrants … why are all the curves flat?  Why isn’t the estimate of illegal alien U.S. residents rising?

What I’ve looked at so far is the gross inflow of illegal immigrants across the border.   The graph above looks at the net number of illegal aliens living here.  Assuming both estimates are reasonably close to correct, there has to be a pretty big outflow of illegal immigrants, back out of the U.S.

So, as a matter of logic, I’m missing a potentially large flow of people in my overall analysis of illegal immigration.  Some fraction of successful illegal immigrants — those who cross the border illegally, and end up settled somewhere away from the border — eventually cross back.  To get at net illegal immigration, I should, in theory, subtract out that flow.

(And there’s also some fraction of that population lost to illegal immigrants who are granted some form of amnesty, and so convert to legal status.  But there hasn’t been a large-scale amnesty program since Reagan, I think.  Maybe there was one under Clinton?  And then there are attempts to convert the ambiguous legal status of individuals who came here illegally as children but are now grown-up Americans — without legal residency status.)

Historically, there seems to have been a reasonably large reciprocal flow of Mexicans returning to Mexico, from the U.S.  In fact, since 2008, more Mexican nationals have left the U.S. than have entered, by some estimates.  (Or this NY Times article, if you prefer a human interest story to mere statistics.).

To that you’d have to add anybody deported from the interior of the U.S., as only those captured near the border are counted in apprehensions.  (And even there, I’m not sure of the status of long-term illegal residents of communities near the border, who end up being deported as illegal aliens).

By all accounts, if you followed the graph above for another couple of years, there would have likely been an uptick.  But not nearly as much as you might guess, purely from the estimated gross flow of illegal aliens across the border.

Thus, the final lesson for today is that the net growth in the illegal immigrant population in the U.S. is far less than the gross influx of illegal immigrants in any year.

It’s a slight mis-statement to put it this way, but our porous border is porous in both directions.

Addendum 2:  Overstays

Prior to (say) 2017 or so, the single largest source of new illegal U.S. residents every year was individuals who overstayed their visas.  They entered the U.S. legally as tourists, students, or workers, with a visa specifying a defined period of residence, or perhaps legal residence when accomplishing some defined task (e.g., a course of graduate study).  And then the U.S. has no record of their departure, prior to the expiration of that visa.

In the FY 2022 Overstay report, by US DHS, 3.67 percent of persons with such visas overstated their visa, resulting in about 850,000 persons who were, for some period of time, illegal residents of the U.S., because they overstayed their visas.

Aside from that one factoid, I gleaned nothing else useful from that overstay report.  It’s not clear to me how much of that is bookkeeping errors, how much is persons who overstayed by a few days, and so on.  How many eventually left.  And so on.

So it’s hard to make much out of that, except to say that prior to the latest increase in likely illegal immigration at the Mexican border, that was consistently the single largest category of annual “illegal immigration”.  Take that for what it’s worth.

Post #1927: Will those who succeeded in immigrating illegally please raise your hands?

 

This is the first of what may end up as a series of posts on the statistics of illegal immigration across the Mexican border.  

Unlike my usual style, I’m just going to present my conclusions here, and put the citation of sources, evidence, and analysis in separate posts.  If I get around to it.  Because, to be fair, the conclusions aren’t what I expected to see.  And this is a topic where I don’t think people’s opinions are much swayed by evidence anyway.

One simple question:  How do they know?

Source: How to Lie With Statistics,

I didn’t intend to do a series of posts on this topic.  I just wanted a simple answer to what I thought was a fairly obvious question.  The most basic question you can ask about a statistic, as shown above.

That snowballed.  But here’s where I started.

You’ll see various posts and news reporting (loosely defined) claiming that millions of illegal immigrants are coming into the U.S. every year, via the Mexican border.

These claims immediately pinged my bullshit detector, for a very simple reason:

How do they know?

For every law enforcement statistic I know of, official numbers count those who were caught.  But here, how do they count the people who weren’t caught, the ones who made it safely (but illegally) into the U.S., via the Mexican border?

Once you start prying away at that question, you soon discover a whole nested set of additional questions. A set of matrioshka cans-of-worms, if you will.

 

But let’s just stop at the first question.

How do they count the people who successfully illegally immigrate across the U.S.-Mexican border? Continue reading Post #1927: Will those who succeeded in immigrating illegally please raise your hands?

Post #1926: A Prius driver takes a pass on Chevy Bolt “one-pedal driving”.

 

Do electric vehicles (EVs) get rear-ended more often than conventional cars do?

They certainly should.

That’s my conclusion after trying out the “one-pedal driving” mode on my new (used) 2020 Chevy Bolt.   And working through the logical consequences of it.

The practical bottom line of this post is that you should think twice before you tailgate an EV in traffic.  Because the chances are good that they can stop a whole lot faster than you can.   And may give you less warning when they do.

Not convinced?  Keep reading the parts in red, below.

Words do not do it justice: An accurate description of one-pedal driving mode.

Source:  Yeah, I know it’s a front-wheel-drive car.  The Gencraft AI doesn’t, though.  Almost all pictures here are courtesy of Gencraft.

Here’s your typical bland one-sentence description of one-pedal driving mode:  “With one-pedal driving, the car has enhanced regenerative braking, and will begin to slow as soon as you ease up on the gas (accelerator).”

Before I bought a Bolt, my reaction to that was, big deal.  Almost all modern cars do that, to a degree.  Anything with an automatic transmission slows when you take your foot off the gas.  All hybrids use regenerative braking, that is, they slow down by generating and storing electricity, reserving the friction brakes (pads pressing on rotors) as a last resort.

Some EVs can now do it more?  Whoop-te-doo.

Now that I own a Bolt, I know that description is missing a key word:  Abruptly.  Or, rapidly. Or, with great force.  Take your pick.

Taking your foot off the gas in “one-pedal” mode is nothing like taking your foot off the gas in a normal or hybrid car.  You don’t coast, at all.  You stop, pronto.  Not quite a wheels-locked panic stop.  But far faster than I normally stop, and far faster than anyone would reasonably expect me to stop in traffic.  In the Bolt, in one-pedal model, take your foot off the accelerator and you pull a few tenths of a G worth of deceleration.  Enough to pull you forward in your seat.  Enough that there’s no way I would engage that mode in snowy or icy roads.  Enough that I’d think hard about it before I turned one-pedal driving on in a driving rain.

Enough, already.  You get the point.  Here’s a more accurate description of one-pedal driving mode:

The act of lifting up on the accelerator, in one-pedal driving mode, is equivalent to pushing the brake pedal.  Hard.  Your (lack of) accelerator pedal is your brake pedal.  It’s not 100% as much force as you can get, if you actually do mash down the brakes.  But it’s an appreciable fraction of it.

You may again think, so what?  So you can, in effect, actuate the brakes, without hitting the brake pedal.  What’s the big deal?

Keep reading.

Brake lights?  We don’t need no stinkin’ brake lights.

But wait, it gets better.

Prior to mid-2023, some EVs would do that — stop fairly abruptly, in one-pedal mode — without turning on the brake lights.  And no, I’m not kidding about that.  (Reference).

The worst of those were fixed via software update, so now, all EVs on U.S. roads will now show brake lights, at some point, during some level of deceleration, in one-pedal driving mode.

As an afterthought.  Does that make you feel better about it?

But even now, an EV manufacturer’s decision on when, exactly, to show brake lights, during rapid braking in one-pedal driving mode, is entirely voluntary, and entirely up to the manufacturer, here in the U.S.A.  And for all of them, those lights turn on after the car has started slowing down.

Oddly enough, if you see this brought up on-line, you’ll see nothing but apologists for it.  Ah, cars have always had ways of slowing down without showing brake lights.  Let off the gas, in an automatic-transmission car.  Downshift in a manual.  Or, if you’re a jerk, hit the parking brake to stop, to fake out the folks behind you.

But those events were either mild in nature (automatic transmission), or rare and mild (nobody in the U.S. drives a manual these days, and nobody in the last 50 years has been dumb enough to wear out their clutch rather than brake pads by routinely slowing the car by downshifting).  Or required outright malice, like using a hand brake to stop.

Now, by contrast, you’re putting out a whole fleet of cars, for Joe and Jane Driver, all of which are designed to be driven without touching the brakes.  Designed to allow for substantial rates of deceleration without using the actual brake pedal.  And for which the decision about whether, or when, to turn on the brake lights at some point during that one-pedal deceleration, is an option for the manufacturer to decide. 

Let me offer a clear contrast to what you are used to, in a traditional gas car.  There, the brake lights are designed to light the instant you rest your foot on the brake pedal.  Brake lights are actuated by a switch that typically sits directly above the metal bar holding the brake pedal.  That switch has a fine adjustment on it.  You literally fine-tune-it so that the tiniest movement of the brake pedal closes the switch.  Even the lightest possible braking pressure will turn on your brake lights.  Properly adjusted, you literally turn on the brake lights before the brake pads make contact with the rotors.

So we now have a mixed fleet of cars on the road.  For 99% of them, the brake lights illuminate as soon as the driver puts on the brakes.  For the remaining 1%, the lights may come on at some point, after the driver has “put on the brakes”, assuming the rate of deceleration exceeds the manufacturer-specified threshold.

Yeah, what could possibly go wrong with that?

Braking distance versus stopping distance.

Definitions:  Both terms apply to panic stops.  Braking distance is how far your car travels, from the moment that you’ve firmly stomped on the brakes, until you reach a complete stop.  Stopping distance, by contrast, is that, plus the distance you travel during your “reaction time”, that is, the time it takes to say “oh shit”, move your foot off the gas, and hit the brakes.

Honking the horn is optional, but highly recommended here in Northern Virginia.

Now for just a bit of math.

1:  It takes about three-quarters of a second to lift your foot off the gas, and put it on the brake, in a panic stop.  That’s in addition to the initial reaction time — the time it takes you to realize you need to stop quickly.  (Estimates vary, that’s my reading of the literature on the subject.)

2:  At 30 miles per hour, in that amount of time, a car moves about two car lengths.  (Calculated as (30 MPH *5280 FT/MI *(0.75/(60*60) HOURS) = ) 33 feet.

3:  EVs in one-pedal driving mode can initiate an abrupt stop without moving their foot to the brake pedal.

My takeaway from all that is that EVs in one-pedal driving mode should be able to panic-stop somewhere around a couple of car lengths shorter than traditional cars.  That’s not due to better brakes, or better drivers.  That occurs because they begin to brake rapidly before they even move their foot to the brake pedal.

Yeah, what could possibly go wrong with that?

Summary

Shorter stopping distance is just dandy if you’re driving an EV in one-pedal mode.  But maybe isn’t such a plus for the person in a standard vehicle, tailgating an EV in one-pedal mode.

If you are in traffic, behind an EV in one-pedal mode, and the EV in front of you makes a panic stop, you need to be aware that, compared to a conventional car or hybrid:

1: That EV is inherently capable of stopping faster.

2: That EV will give you less time to realize it is stopping.

And nothing about that car will give you the faintest hint that those two factors are in play.

You’ve been warned.

Background:  Regenerative braking the Toyota way, or why Bolt one-pedal mode does me more harm than good.

We changed the brake pads on my wife’s 2005 Toyota Prius sometime around 140,000 miles.  Up to that point, the brakes hadn’t needed any attention.

The crazy thing is, that’s not even brag-worthy.  Going 100K miles between brake jobs is normal for any car with regenerative braking.

The Prius has regenerative braking.  To the greatest extent possible, the car slows down by turning itself into an electric generator.  It converts the forward momentum of the car to electricity, which then charges the traction battery.  Cars with regenerative braking routinely go 100,000 miles between brake jobs.  So says the U.S. DOE.

No material efficiency gains — for me.

The reason for the low brake wear in a Prius is that almost all the braking energy is done electrically.  In an ideal gentle stop, the friction brakes only kick in below about 5 MPH.  (If your rotors have surface rust, and your windows are open, you can hear that happen until you knock the rust off the rotors.)

In an idealized stop from 30 MPH to zero, you can easily calculate the fraction of braking “power dissipation” accounted for by electrical generation versus friction brakes.  Kinetic energy goes as the square of the speed, so, in a hypothetical gentle stop from 30 MPH to 0 MPH, where the friction brakes only handle the part below 5 MPH, the fraction of braking energy is:

Friction fraction of braking energy = 5-squared/30-squared = 25/900 = ~3%

Electrical Fraction of braking energy = 1 – friction fraction = 97%.

In other words, with a reasonably gentle stop, in typical suburban traffic, regenerative braking (Toyota-style) converts about 97% of the car’s forward momentum to electricity.  You don’t get to keep all of that, because there are losses in the electric motor/generators, the wires and charging electronics, and in charging the battery.  Maybe you keep 80% of that, or so.

One rationale offered for EV one-pedal driving is that it improves efficiency by recapturing more of the potentially available energy from braking the car.  That’s because you can literally bring the car to a full stop, and so, in theory, capture 100% of the car’s forward momentum and convert it to electricity.  Of which, again, you might be able to keep and use maybe 80%, after all the relevant losses are factored in.

And that’s the main reason that Bolt one-pedal driving does more-or-less nothing for my driving efficiency.  Because, despite what you may read, the Bolt’s regenerative braking does more-or-less the exact same thing as the Prius, during moderate stops.  In normal (not one-pedal) driving, when I take my foot off the gas, the car begins to recapture energy through regeneration.  And when I push gently on the brake, it begins to capture even more energy through regeneration.  Just like a Prius.  (All you have to do is look at the dashboard, as you brake, to see that this is true.)  And in a normal, gentle stop, with rusty rotors, you can hear the Bolt friction brakes engage at about the same speed as the Prius — about 5 MPH.

I guess if you drive like a bat out of hell, regenerative braking can improve your efficiency somewhat.  Plausibly, those who routinely make quick stops can benefit from converting more of the stop to electricity, before the friction brakes kick in.

But my driving habits were formed during the Arab Oil Embargoes/energy crises of the 1970s.  And I’m cheap, to boot.  So I try to avoid rapid stops.

My gut reaction, from reading about this, is that the real fan-boys for one-pedal driving are, in fact, those who want to drive like a bat out of hell.  They like it for the “sporty” feel, and how it lets them zip around all that much faster.  Which, to me, makes the whole “efficiency” argument kind of silly.  If you drive that way, clearly efficiency isn’t your goal.  You’d get more miles per KWH by not trying to drive the Bolt like a sports car.

So, from my perspective, as far as efficiency goes, one-pedal driving provides a marginal improvement in efficiency, for those with habitually inefficient driving styles.  Turning that around, if you’re a laid-back driver by nature, you ain’t going to get much additional efficiency out of one-pedal driving, beyond what you get from regenerative braking in “normal” driving mode.

Extras for experts, 1:  There is one weird final twist on this, in that, in a hybrid, regenerative braking doesn’t much matter.  It might typically add just 2% to the vehicle’s overall efficiency.  That’s from a combination of factors.  First, even with the efficient Atkinson-cycle engine of a Prius, you start off by wasting 60% of the energy in the gasoline.  Second, with relatively small electric motor/generators, and most importantly a relatively small battery, the amount of regenerative braking force — the amount of current you can safely generate and squeeze into the battery, without damaging anything — is highly limited.   So for the U.S. EPA drive cycle, with its extended periods of fast stop-and-go driving, you tend to show only a modest amount of energy recapture, as a fraction of the total energy used by the vehicle.

In an EV, by contrast, regenerative braking is a much higher contributor to overall vehicle efficiency, as the Federal government measures it.  First, unlike a hybrid, all the inefficiency in converting fossil fuels to electricity is “off the books”, so to speak.  That occurs at your local utility, not in your car.  The calculation of overall car efficiency starts with charging it, so as a whole the vehicle appears to have vastly less total wasted energy, than a hybrid does.  Second, with large motors and much larger battery, you can safely put more current into the battery.  Thus, in a hard stop, an EV can likely capture more of the energy than an hybrid can, prior to applying the friction brakes.

Old dog, new trick — look ma, no brakes!

The first thing about Toyota-style regenerative braking is that it’s absolutely seamless.  In the best case, you wouldn’t even guess that the car had this feature.  Only if you listen very closely, and brake very slowly, can you discern the point at which the friction brakes are engaged.

The second thing about Toyota-style regenerative braking is that hybrids with regenerative braking behave exactly the same as any non-hybrid car with automatic transmission.  Take your foot off the gas, and the car begins to slow just a little bit, just like any other automatic-transmission car (then) on the road.  The harder you push on the brake pedal, the more braking force you get.

Regeneration in the Bolt, by contrast, feels nothing like a normal car in this regard.  It is far more aggressive, even in normal (not one-pedal) mode.  Take your foot off the gas in a Bolt, and you slow much faster than you would in a standard car with automatic transmission, or in a typical hybrid.  I have already had to break myself of the long-learned habit of lifting my foot from the gas when I see a red light ahead.  On the roads around here, If I were to do that in a Bolt, I’d come to a dead stop long before I make it to the light.

But I can live with that.  I lift my foot, eyeball the dash, and look for the something close to zero KW going into or out the battery.  It’s hardly a life-changing difference in driving technique.  Not after I had to re-learn driving for the Prius Prime, and its preference for constant-power (instead of constant-force) acceleration (Post #1618:  There ain’t no disputin’ Sir Isaac Newton).

But switching to one-pedal driving has one potentially life-changing difference:  You may lose the instinct to put your foot on the brake.  If you never need to panic stop, you can literally drive the car in one-pedal mode and never touch the brake.   (Some one-pedal fans brag about doing exactly that.)

So do I, as a 65-year-old guy, now want to train myself to drive in one-pedal mode?  This, when the approach to driving is so different from our other car (a Prius).  And this, where driving in this new style means basically to ignore the brake pedal.

Short answer, no.  Sooner or later, in NoVA traffic, I’m going to have to do a panic stop.  And when that happens, that panic stop happens on instinct.  It took me close to 20 years to get used to ABS, and to lose the instinct to release the brakes in response to a skid, and just keep my foot mashed to the floor.  I really, really don’t want to lose the instinct that tells me to hit the brakes in an emergency-stop situation.

So, it’s not that I couldn’t learn this new trick.  It’s that I probably shouldn’t.  Not with driving two different cars.  And not with my recent entry into geezerhood.  Better to leave sleeping dogs lie.

The Prius Gene

This is a true story.  We bought our first Prius in 2005.  The same week that we bought ours, hundreds of miles away, with no communication between us, one of my brothers also bought his first Prius.

We’re now a two-Prius family.  I think my brother and his wife have been a three-Prius family, with one going off to Prius heaven as a result of a freak highway accident.

My brother says the exact same thing about his Prius, as I say about ours:  It pushes all my buttons, in just the right way.  From the super-smooth acceleration with no gear shifts, to the dashboard feedback on mileage, pretty much everything about the car says “relax, chill, enjoy the drive”.

Maybe we both like that because that’s pretty much the way my dad drove.  Maybe we inherited the genes that give us that bent.  In any case, it seems to run in the family.

It takes some work to drive a Bolt as if you were puttering along in a Prius.  But for whatever reason, by golly, that’s how I choose to drive it.

So, no one-pedal mode for me.  It’s insufficiently Prius-like.

Post #1925: Bolt EV, party like it’s 1999.

 

The last car that I bought, before buying a used Bolt a) had a manual transmission, b) had a CD player, c) had no USB ports, not even for charging, and d) could only communicate with the outside world via the OBD-II port, as God and the U.S. EPA intended.

And, needless to say, ran on gasoline.

Continue reading Post #1925: Bolt EV, party like it’s 1999.