My wife and I just returned from a brief vacation in Ocean City (OC), Maryland.
Our annual OC vacation has changed since our kids have grown up. Without the need to entertain the kids, the beach experience becomes a lot more, eh, ritualized, for want of a better term.
As I put it to my wife, a guy metal-detecting on the beach, with his kids, that’s wholesome family fun. By contrast, a fat, bearded geezer walking the beach alone, with a metal detector? Best I can hope for is “geek”, with overtimes of “harmless weirdo”.
Activities that are appealing with kids, but not so much without them, account for a lot of the change. Kite flying. Amusement parks, amusement rides, boardwalk shops, toy stores, boardwalk food, and so on. A combination of things you wouldn’t do without kids in tow, and food you definitely wouldn’t eat, ditto.
Topped, of course, by miniature golf. At the beach, that’s a pleasant two-step time-consuming process. First you spend considerable effort choosing which fantasy landscape you wish to golf through, from among the miniature golf courses in Ocean City. (When in doubt, choose dinosaurs.) Then actually golf it.
Anyway, once we skip the mini-golf etc., the adult vacation boils down to places to eat, places to shop, and places to sit. Maybe walk. Maybe swim.
A new high price for public car charging.
We drove my wife’s 2021 Prius Prime. The trip is about 175 miles each way, mostly high-speed roadway. Using gas only, no battery use, we got 68 mpg going out, and 66 mpg coming back. More-or-less identical to the mileage we got last year (Post #1458). So, nothing exceptional for this car, but far better than the EPA rating.
We got a surprise when we charged the car, in a little Delaware shopping center, at the same private no-name charge point that we used the prior year. No prices were posted. We went ahead anyway. Net cost: $5 per KWK. Or roughly 80x what we pay at home. For the Prius, the break-even price of gas (see Post #1656 for details) would have been ($5/0.074 = ~) equivalent to $66/gallon gasoline.
Now, I know that public chargers are expensive, as documented in Post #1548. But the highest price I could verify via internet search was $1.25/KWH, with a median somewhere around $0.50/KWH.
The credit card transaction hasn’t yet finalized, so it’s possible that they just routinely put a $10 hold on the card, but actually charge much less for the final transaction. OTOH, I may just have paid $5/KWH. So far, I have not been able to track down the company that owns the charger.
Live and learn. As a tourist, I expect to pay handsomely for everything. But not quite that handsomely. So, caveat emptor. The world of charging stations remains a bit of a Wild West. At least in tourist areas.
A puzzle regarding house electricity.
Now we get to the heart of the posting.
We vacation every year in Ocean City because it’s my wife’s family’s tradition, begun when her mother (and uncle) together bought a share of a new four-flat beach-block condo.
We return each year to that same — but now very aged — condo. It’s old. With lots of exposure to rain, sun, and salt air.
This year, the lights were flickering. Just a fraction of a second, but quite frequently. Just enough that you’d catch it out of the corner of your eye. Separately, if fridge or microwave were running, they’d sag along with the flicker of the lights.
It eventually dawned on me that the problem had to be with the electrical system of the building (or maybe the grid), not the separate lights and appliances. I walked around the house, and noted three oddities. One is that ours is the last building on the street with above-ground utilities. Two is that all of the old electromechanical meters on this building had just been replaced by solid-state meters. And three, there was a solid aluminum bench resting against a rusting steel electrical box. Attached to the building.
I carefully moved the aluminum bench away from contact with the metal box. The flickering stopped. (That’s not my imagination, as my wife agrees.)
I think that tells me that there’s something quite wrong with the electrical system of that condo. But it can’t simply be a bad ground. Because removing an additional conductive path to ground seemed to fix the problem. The problem only occurred when this “extra” ground — the aluminum bench — was in place.
I had no tools with me to try to pin it down further. So I left it at “I’m sure that’s wrong” and “I have no idea if that’s serious or not.”
So that’s the take-home quiz I brought back from this vacation. Assume the earth was nicely damp and conductive. Why would resting a conductive metal bench against a rusty steel electrical box cause ongoing fractional-second voltage dropouts? And removing the bench then stopped that.
I’ve been looking for a couple of hours and I still have no clue. I think I’m just going to describe this to the folks who manage the building and let them hire a pro from there.
Addendum: It makes no sense that adding more grounding, to a grounded system, would cause a problem like this. The majority opinion is that the problem itself — those flickering lights — is most likely caused by a loose (i.e., high-resistance) neutral wire. Providing a better earth ground should make the flickering better, not worse.
But suppose that the metal bench in question wasn’t allowing current out of the electrical system. Suppose it was allowing stray current into the system.
The there is at least one possible explanation: We’re picking up on some neighbor’s power problem.
I came across a posting by one individual (House #1) whose lights were flickering because his next-door-neighbor’s house (House #2) had a faulty neutral connection to the power lines. That high-resistance neutral resulted in current being injected into the ground, via House #2’s earth ground. Those stray ground currents then took the path of least resistance, and returned to the power pole, in part, through the ground/neutral system of House 1. Causing its lights to flicker.
So let me posit the following explanation.
- The National Electrical Code did not require earth grounding of electrical systems until 1978.
- So, this OC condo may not actually have any earth ground.
- Alternatively, it’s so old, and salty sand is so corrosive, that it may no longer have a properly-functioning earth ground.
- If so, then leaning a metal bench, against the rusted metal electrical box, effectively provided an earth ground, and electrically connected the house neutral to earth.
- Other buildings on the street are much newer, and so were probably required to have an earth ground.
- The area is filled with pipes of various ages and types, feeding the closely packed residential buildings, providing high-conduction paths near the building.
- Wet, salty sand has relatively low resistance. I’ve seen 10 ohms per meter, I’ve seen estimates as low as an ohm per meter.
The upshot is that if one of the large neighboring buildings has some sort of electrical problem, and is injecting a lot of current into the ground, then by placing an aluminum bench between my condo’s steel electrical box and ground, in an otherwise-not-earth-grounded building, I’ve provided a path for my neighbor’s ground currents to use my building’s neutral wire, to return to the grid. And thereby cause my lights and appliances to flicker.
That’s all guesswork on my part. But so far, that’s the only guess that fits the facts. I’m still going to suggest that the folks who oversee the condo hire an electrician to check this out.
