Category: Environment

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 #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.

Post #1921: Psychrophilic bacteria for winter composting, setting up the experiment.

 

You might reasonably think that a post featuring my rotting kitchen scraps is a new low for this blog …

… though I’d bet there are some in the Town of Vienna who might disagree.  But that’s water over the dam.

In any case, you’d be wrong, because today I treated half that pile of rotting kitchen scraps with cold-water pond … eh … stuff.  That converts this pile of rotting (or, more precisely, non-rotting) garbage from a mere oddball gardening obsession into an exciting citizen-scientist experiment.

Anyway, as promised in Post #1917, I leveled up the two compartments in my tumbling composter and added cold-water pond treatment to one side.  This stuff:

The idea being that a big dose of psychrophilic (cold-loving) bacteria might jump-start my kitchen-scrap composting.

Composting activity has pretty much ground to a halt, due to the cold outdoor temperatures, despite my having built a little insulated solar shed for the tumbling composter.

Methods:  After leveling up the two sides of the composter, I added about a third of the bottle to one side of the composter,  in several small doses, tumbling the compost vigorously with each dose.  And added a packet of something advertised as enzymes to break down cellulose (though that seems more than a bit far-fetched to me, for reasons I won’t go into).  I’ll tumble it daily, maybe add another treatment in two weeks or so.

In a month, I’ll check to see whether or not the level of compost in the left (treatment) side has dropped materially below the level in the right (control) side.

This is my last-ditch effort to get my tumbling composter to continue working through the winter.  This pond treatment cost $30, so I figure I ought to try to get my money’s worth.  If the stuff doesn’t work for this use, at least I can affirmatively document that it doesn’t.  Hence running this as a controlled experiment, instead of just dousing the whole batch of compost at once.

I’ll be surprised if it works.  But that’s what experiments are for.

Results in a month.

Post #1919: Salted Leafs and Bolts, an unexpected twist in my search for a used EV.

 

I’m in the process of narrowing down the used EVs I want to look at.

I just got a rude, but entirely logical, surprise.  It turns out that a lot of the late-model used EVs for sale in this area are salt-belt refugees.  That is, they were sold new in northern states, where they salt the roads heavily all winter long.  But were shipped south for re-sale as used vehicles.

The story.

Based on the ratings of car dealers on-line, I’ve focused on a couple of independent used car dealers in my area.  (FWIW, Kingstowne and Eastern’s Sterling).  I think maybe the phrase in italics is key, because these aren’t new-car dealers accepting trade-ins.  These are used-car dealers.

As I was doing my on-line due diligence, seeing what I can see about these cars by VIN, I happened to notice that one car I’m interested in — a 2021 low-mileage Bolt — was originally sold in Michigan.

Hmm.  Funny that this car ended up in Virginia.  But people move, and so on.  And yet …

I tracked down the original state of sale for the other two I’m focused on — 2020 and later, relatively low mileage.  Those were originally sold in Upstate New York, and Vermont.

One salt-belt car might be by chance.  But every car I’m looking at?  Highly unlikely that’s a coincidence.

I can guess what’s driving this.

EVs lose a lot of range in cold weather.  That’s a fact.  None of these cars has an efficient (heat-pump) heating system.   Also a fact.

I have to guess that:

  1. You have a lot more dissatisfied owners in cold-climate states.
  2. You get a much better resale price on these vehicles, in warm-climate states.
  3. So there’s a steady trade in shipping used EVs south for resale.

The issue isn’t that these were driven in the cold.  The battery management systems on these cars will all prevent the owners from damaging the batteries permanently by (e.g.) charging when the batteries are below 32F.

The issue is that all of these cars are salt-belt refugees.  That is, they were driven in the states where roads are heavily salted, for a significant fraction of the year.

After a few months of watching YouTube auto mechanics in salt-belt states (Watch Wes Work, from Illinois, and South Main Auto Channel, from upstate New York), one thing that comes through loud and clear is that salt is incredibly destructive.  Among the things I learned from those videos is the term “rust jacking”, which is when the accumulation of rust literally bends and breaks metal parts of the car.  Never seen that around here, and I’ve owned a lot of crappy old cars.

And so, once again, I need to stop and cool my jets, as I give this a re-think.  And look at what’s available as a used vehicle, from local new-car dealers.

Post #1918: Falling Leafs, fallen Bolts: The trend in used EV prices in my area.

 

I don’t drive much.  I haven’t had a car for a couple of years now, and have gotten along  by borrowing my wife’s car, when convenient.

I’d like to get my hands on a nice, used EV.   That’s a good choice, given that I’m going to use this for a grocery-getter and little else.

Depending on the price, of course.  And I’m clearly in no hurry to buy one.

Back in July I looked at my local market for used EVs and narrowed my best option down to a 2018 or later Nissan Leaf.  That’s laid out in a series of posts around Post #1837, and the posts just prior to that.  The year cutoff was due to a change in the Leaf battery chemistry that year, to a much more stable (long-lived) battery.

I have been checking back occasionally ever since.

And I’ve been reading articles suggesting a steep decline in the price of used EVs.  I see talk about price declines on order of 30% per year.   This is almost always attributed to the fact that most used EVs are Teslas, and Tesla made some steep price cuts to their models this past year.

In other words, a falling tide sinks all boats.  Those Tesla price cuts are rippling through the entire used EV market.

But in addition, Chevy cut the price on the Bolt last year.  Both to spur sales, and maybe because the Bolt was plagued by a significant recall due to battery fire issues in a handful of vehicles.  Chevy claims that’s taken care of, but they ended up replacing the batteries in tens of thousands of cars.

In any case, when I went back to re-assess my local market for used EVs, it sure did seem like prices were down.  So I did my best apples-to-apples comparison between what I looked at back in August, and now.  As shown above.

By my estimate, asking prices for a used late-model Nissan Leaf fell 14% in the last five months of 2023.  Or … on-order-of a 30%/year rate of decline. 

More interestingly, I can now get a used Chevy Bolt for about the same price as a used Nissan Leaf.  This is a change from the prior analysis, where my back-of-the-envelope on a Bolt of this vintage, five months ago, put the average asking price at $21,000.

But now, consistent with the decline in the Leaf price, there’s been an even steeper decline in the Bolt price.

Objectively, the Bolt looks like a lot more utility for the money.

  • The Bolt has about 90 more miles of range than the leaf (about 250, versus about 160 for the base Leaf)
  • It uses a standard (J1772) plug, instead of the soon-to-be-obsolete CHADMO plug on the Leaf.
  • It has active battery temperature management, compared to the Leaf’s passively air-cooled battery.

The sole drawback from my perspective is that the Bolt looks like a tiny little car, where the Leaf does not.  To me.  They have roughly the same interior volume, and the Bolt actually has a higher curb weight than the base Leaf.  But the Bolt is shorter by about a foot-and-a-half.  Just enough that I notice how small it is, compared to (say) the 2021 Prius that my wife drives.

For either car, if you had little enough income in the year of purchase, Uncle Sugar will give you a $4K tax rebate for purchasing that used US-made EV.  (Yep, for purchasing a used US-made EV.  Part of the Biden Administration’s buy-American industrial policy intersecting with its global warming initiatives. So, thanks, Joe Biden. I guess.)

Rumor has it that the big drop in the Bolt price is due to Chevy rehabbing and re-selling a lot of those recalled vehicles.  I’m not sure how much that is true.  What I am sure is that the Bolt looks like a pretty good option, if you trust Chevy to have fixed that rare battery issue.  If you pick and choose, you can plausibly pick up a three- or four-year-old car, with about 10K miles on it, for a net $13K or so.

This, where the only expensive component — the battery — comes with a mandatory eight-year/100,000 mile manufacturer’s warranty. Which should, in theory, take a whole lot of the risk out of this used-car transaction.  Roughly speaking, you pretty much have to get at least five years of driving out of the car, or the manufacturer (not the seller!) has to replace your battery.

As used cars go, that seems like a pretty decent deal, regardless of the fuel source.  The fact that this is the low-carbon alternative is almost gravy, at this point.   To me, based on what I’ve been looking at, this now looks like it’s just a pretty good deal on a used car.  Period.

I have to confess that the first and last Chevrolet product that I ever bought was a Chevy Vega.  It was a traumatizing experience in many regards, as those of you familiar with the history of the Chevy Vega will understand.

I guess, going on 40 years later, maybe I can find it in my heart to forgive, and give Chevy another try.

Post #1917: Composter shed failure

 

Many of my readers have been breathlessly awaiting the results from my composter-shed experiment (e.g. Post 1899).

Unfortunately, that breathlessness is not explained by the stench of rotting kitchen scraps.

In the winter cold, my tumbling composter is not so much a composter as a mausoleum.  It’s the Lenin’s Tomb of potato peels.   Each time I visit it to dump in a new batch of scraps, I soberly reflect upon the perfectly preserved remains of ancient meals resting comfortably within.  I ponder what that means for the future.

Source for title photo, via Wikipedia:  By Russia, Lenin’s Mausoleum or more specifically image, Fair use, https://en.wikipedia.org/w/index.php?curid=48098730

Background

Recall the issue here:  I toss my kitchen scraps in a tumbling composter.  Three seasons of the year, that works great, and the compost is really desirable for gardening.  But when the weather turns cold, the composter stops working, for all intents and purposes.  I then have to throw my scraps into the trash, where they eventually become trash-to-electricity “biofuel” when Fairfax County incinerates them.

I refuse to heat my composter with electricity.  And I’m not going to bring it inside for the winter.  So … how about trying a solar-heated “shed” for it?

Bottom line:  Passive solar through double-paned glass, plus insulation, and radiant barrier, together, provides nowhere near enough heat to keep this tumbling composter running during the winter.

I suspect that adding more insulation would be fruitless. 

First, the shed does, in fact, keep the temperature of the compost up, when the sun shines.  But with a fairly large ratio of surface area to volume, a string of cloudy days allows this to cool right down to ambient temperature.

Second, the resulting “cold snap” kill off any insects in the compost.  I like to think of a composter as a place for bacterial decomposition of kitchen scraps.  But in fact, I’ve never really known what fraction of decomposition was insect-drive, versus bacterial.  Typically, when I open this composter to add material during spring/summer/fall, I can see insects (larvae) working on the contents.  But all it took was a few freezing nights to stop all insect activity.

My take on it is that adding an inch of foam board to the existing shed isn’t going to fix that.

What are the other options?

Psychrophilic, qu’est-ce que c’es?

Source:  All pictures in this section are AI-generated with the prompt “cold, hungry bacteria”, using Gencraft.com.

Composting small volumes of organic material in cold weather is a common problem.  Near as I can tell, the suggested solutions are:

  1. Compost a large enough volume that the pile stays warm outdoors.
  2. Store your kitchen scraps over the winter, in some location.
  3. Move to indoor worm composting for the winter.
  4. Give up.

I don’t find any of these options particularly appealing.  I don’t generate a large enough volume of organic matter for 1) above, and the Virginia climate is not well-suited to 2) above.  I can’t depend on the kitchen scraps remaining frozen, outside, in a typical Virginia winter.  And I’m not too keen on having five-gallon buckets of garbage sitting around, even if they are sealed.  I’m guessing my neighbors wouldn’t be all that keen on my digging a garbage pit in my back yard.  At least, not if they knew what I was up to.  I don’t want to get into 3) indoor worm composting, though I am finally beginning to grasp the potential advantages of that over traditional outdoor composting.

Arguably, the smart option is 4) give up, per the recommendation on this website.

(Finally, I’ve already dismissed the idea of an indoor electric “composter”, that is, combination grinder and food dehydrator. Just not my cup of tea.

My last gasp at making this tumbling composter work in the winter is to track down some “psychrophilic bacteria”.  That’s the term, per this U. Mich. website, for the cold-loving bacteria that break down organic matter even in colder temperatures.  (The same website says that a cubic yard of organic matter is the smallest pile likely to continue to hot compost in a Michigan winter.)

First, the idea of cold-tolerant decomposing bacteria is a real thing.  You can find it in the scholarly literature (e.g., this reference, for psychrotrophic bacteria).

I have no clue if spiking my compost with psychrophilic/psychrotropic bacteria will work.  (As you have probably already guessed, the prefix “psychro”- means “cold”.)  Everyone says these cold-adapted bacteria work slowly, but they do continue to work, even in the cold where other bacteria would not.

And that doesn’t matter anyway, until I can figure out where I can buy the little buggers.   

I haven’t found anything specific to composting.  Apparently the approved solution to winter composting is to have a big enough compost pile.  That said, I seem to find two plausible sources.

Pond cold-weather bacteria.  The first thing I came across is cold-weather bacteria for (decorative) ponds.  Apparently, you spike your pond with these to keep decomposition going in colder weather.  Here’s an example.  Here’s another example.  Amazon offers dozens of choices.

Main-line drain maintainer.  It also occurs to me that I can buy stuff at Home Depot that advertises that it spurs decomposition within your main sewer line.  Those lines sit at around 55F in this area (although the incoming materials may be warmer).  So it’s plausible that dumping that stuff, in my tumbling composter, might aid decomposition.

Of the two, I think the pond bacteria would be the better choice.  All of those products appear engineered to break down cellulose.  The drain cleaner, by contrast, is advertised to break down “grease, hair, paper, oil, soap scum”.  The pond bacterial additives appear to be directly targeting the type of organic matter I’m dealing with, the drain cleaners are not.

The proposed experiment.

As it turns out, I’m going to have to shell out something like $30 to buy some fall/winter pond treatment.  And my composter conveniently has two compartments.  So I might as well set this up as a proper experiment.  I’m going to mix up and level out the materials currently in the two sides of the composter.  Add fall/winter pond bacteria to once side.  And see if I notice any difference in the remaining volume of materials, one month from now.

I can’t find winter pond bacteria locally, so I’ve ordered some from Amazon.  This stuff.  Several comments attest to the fact that it works in cold weather.  And stinks.  And that’s, eh, more-or-less what I’m after.

Results in a month.

Post #1912: What the watt?

 

A few years back they tore down the modest house across the street from me and built a house in the Vienna Modern style.  Which is to say, the biggest possible house that would legally fit on the lot.  That’s all they build in this Town, and has been for at least the past 15 years.

Having watched this house (and many like it) go up in my neighborhood, I can tell you that it isn’t a particularly energy-efficient design.  It’s standard 2×4 construction with fiberglass batt insulation.  Not significantly different from the way houses were being built half-a-century ago.  There was a Tyvek wrap put on under the siding, which is good from an energy consumption standpoint.  But that’s far more than fully offset by the large amount of glass area, which is bad for energy consumption. You can’t see it here, but most of the northwest-facing back of the house is glass.  Which is a dead loss for energy consumption.

Consistent with that, none of the several vehicles associated with the house is fuel-efficient.  I think I’ve spotted a couple of full-sized SUVs, plus the obligatory shiny new truck.  All old-school straight gas engines.

This neighbor has a penchant for having the exterior of his house decorated with lights and gizmos to suit every season.   In the Christmas season, his professionally-installed lighting outshines the adjacent street light.  As you can see from the photo above, it stands out on what is otherwise a fairly low-key street.

Since I’ve been spending some time researching Christmas lights, I got to wondering just how much energy that light display requires.  Just for lighting the eaves of the house.  (I’ll ignore the bushes and fences, which are wrapped in what appear to be mini-LED strings.)

So, what’s your guess?  Only the two sides shown here are lit.  The other side and the back are dark.  Does that much lighting require roughly:

  1. 100 watts
  2. 250 watts
  3. 500 watts
  4. 1000 watts
  5. Over 1000 watts

It’s easy enough to estimate.  Count the bulbs, and multiple by an estimated watts per bulb, given that these are almost certainly LED C9 bulbs.

The correct answer is b. That’s about 320 C9 LED bulbs, and each such bulb takes somewhere between 0.6 and 1.0 watts.  So the whole set consumes somewhere between 200 and 320 watts.  Call it 250 at a guess.

Plus the lights for the shrubs and fence.  Arguably somewhere around 400 watts for the entire display.

That strikes me as remarkably little electricity, for that over-the-top amount of lighting.  But I grew up in the era of incandescent lighting.

I reckon that the carbon footprint for that light display, for the entire season (it was put up a couple of weeks ago), is no more than 100 pounds of C02.  (Calculated as 28 days x 14 hours per day x 0.4 kilowatts x 0.65 pounds C02 per KWH.)  Or roughly what you’d get from burning five gallons of gasoline.

Obviously, even if you wanted this sort of over-the-top, brightest-house-on-the-block display, you could cut the energy use in half with the addition of a $5 timer.  Just turn the lights off from (say) midnight to dawn, when nobody is out-and-about to see them.   The fact that he doesn’t bother to do that demonstrates exactly how much he cares about the consequences C02 emissions in the modern world.

If a tree falls in the forest, where no one can hear it, does it make a sound?  You can philosophize over that all you want.  But for sure, a light display that no one can see still uses energy.  That makes this all-night lavish lighting display a poster child for just how little effort some people are not willing to go to, to rein in their C02 emissions.  Not worth five bucks for a timer.

Once upon a time, you could make a “base load” argument for the relative harmlessness of nighttime energy use.  It’s difficult or impossible to throttle down coal-fired and nuclear power plants on a daily basis.  Where coal is still the backbone of the electrical grid, electricity use in the dead of night (when demand is otherwise down) required minimal or no additional fuel consumption beyond that “base load” floor that must be maintained.  But with the transition of the grid from coal to natural gas turbines, where power plants can be fired up or shut down relatively quickly, that’s an increasingly obsolete argument.  Shifting electricity consumption to off-peak periods may reduce the total amount of generating equipment (capacity) that a system requires, but I don’t think it has much impact on the amount of fuel burned.

But I think this extra-bright light display underscore that the future is electric.  Some people are simply programmed to be energy hogs.  I’d bet it never even occurred to my neighbor that he could have his installers add a timer to the system.  But modern LED lighting makes up for his indifference to energy waste, effectively putting a cap on the amount of energy that even the most determined energy waster can use.

Sure, he could waste more energy if he tried.  But the point is, he’d have to go out of his way to do that.  If he doesn’t give it a thought — and I’d say that’s likely here  — LED-as-default acts to moderate the environmental impact of the resulting excess.

The upshot is that, courtesy of LEDs, this entire “brightest house on the block” lighting display turns out to be … fairly harmless, environmentally.  In the grand scheme of things.  And since old people are set in their ways, and aren’t going to change even as global warming progresses, we need more of that sort of self-limiting process.

The nicest thing about it is that as renewables’ share of electricity generation increases, and the carbon-intensity of the grid falls, displays like this should become ever-more-harmless in the future.

And so, if that all proceeds according to plan, at some point in the future, our kids can look at a display like this and only think of Christmas, and nothing else.  Which would be an improvement over their parents’ generation.

Post #1911: LED Christmas light life expectancy.

 

This post goes way over the TL;DR line.  If you want to get to my summary on buying LED Christmas lights that will last a while, go to the Conclusions section in red, below.

Source:  Except where noted, images in this post are from the Gencraft.com AI with a prompt of “Christmas lights”.

Intro:  The ghost of Christmas lights past.

My parents had the same sets of Christmas tree lights for my entire childhood.  And then some, given that I was the youngest of four children.

I, by contrast, am getting ready to toss (recycle) yet another couple of strings of dead Christmas lights.   In this case, some elderly miniature incandescent light strings that started off the season dead.  Again.  And for which I am finally throwing in the towel. Continue reading Post #1911: LED Christmas light life expectancy.