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Electric charges

For the past three days it has been breezy here. Our campsite is on an exposed plateau with no natural windbreaks for miles in any direction, and it's springtime, the season of fair weather breezes. Occasionally a gust will come up and rock the trailer slightly, which is actually kind of fun. We're in no danger of tipping over until the winds get to hurricane force, and even then they'd have to hit us broadside.

But last night the wind really came up and it has remained strong into this morning. Storms from California are coming through, which for us desert-dwellers means wind, occasional cloudiness, and a slight chance of scattered showers. This is a nice change. The rapidly-moving clouds give the desert a dappled appearance, and the rain showers and virga by the mountains are beautiful to watch.

Yesterday we headed over to Ramsey Canyon again for a quick browse through the bookstore. On the way up the road we nearly ran over a rather larger gopher snake. It was about three feet long and very thick in the cross-section. So the first books we checked out were all about identifying reptiles of Arizona, but ultimately we settled on a book about western birds.

Ramsey Canyon bookstore.jpg
Buying books at the Ramsey Canyon bookstore

The clouds today cut into our ability to make power through the solar panels. Even though our current campground offers a full hookup, they charge separately for electricity, so we were considering just leaving the power off and living off solar alone. This got me thinking ...

Metered electric for daily stays is something we've never encountered outside Arizona. It's common for monthly stays, but most places doon't bother for short-term visitors. The reason they do here is simply that some people will flagrantly waste the electric if they think it's "free". Here in air conditioning country, the campground owners are forced to encourage conservation or lose money. I can see why. In the past month I've walked past many an empty trailer or motorhome with the roof air running all day long, even on comfortable days in the 70s.

For our three days in Huachuca City, temperatures have been ideal, so we haven't needed air conditioning. But since the campground provided an easy-to-read meter right at our site, I thought it would be interesting to see how much power we actually used. It turns out that we used 19 kilowatt hours in three days, or about 6 kilowatt-hours per day. That's a lot more than we consume when boondocking, and much more than our solar panels can generate.

Why the discrepancy? Well, when we plug into AC power, a lot of new power loads get introduced. Our refrigerator automatically switches to AC, which draws up to 2.7 AC amps, or 324 watts. I am not clear on whether the electric element in the refrigerator cycles on and off or runs continuously, but if it ran continuously, that would be a potential 7.7 kwH per day all by itself. In any case, the refrigerator uses more power when running on AC than the combined output of both our solar panels. That's why, when we are unplugged, energy for the refrigerator is provided by propane instead.

Another load is the power converter. It takes AC power and converts it to DC to maintain the batteries, with some efficiency loss. You can actually hear that loss when the electric cooling fan in the converter cycles on. What it's telling you is that it is blowing some of that wasted power away in the form of heat.

Finally, human nature takes hold, and we tend to use more lights, and leave them on longer, than we would if were thinking about conserving battery power. Other electric toys get used, too. Eleanor breaks out the electric coffee pot and the toaster for breakfast. We all use the microwave to heat things quickly. We also are able to run our big TV, so a two-hour family movie costs us about 0.2 kwH. All of this luxury boosts our power consumption from a meager 1 kwH per day to just over 6 kwH per day.

For this lesson, I was happy to pay the campground $2.47 for three days of electricity right before we departed Huachuca City. We've towed the Airstream back up to Tucson and will remain here three nights. We've got mail to pick up at General Delivery, there's the County Fair, and we've got a bit of homework to do for Emma's future school. Then the plan is to migrate northward and explore some of central Arizona.

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