Solar Suds
This is the 3rd day of heavy overcast out of a predicted 4-1/2, and that will be followed by another couple of partly cloudy days, so the Defiant’s solar systems are getting a workout. If you have not looked back at past posts, the Mighty Defiant has three independent solar systems, each dedicated to specific tasks. The (2) house batteries power ignition for the fridge, water heater, water pump, and lights, as well as the iPad that I’m typing this on and the iPhone4 that connects it to the cellular Internet. At night, the house batteries also power 3 ultrasonic speakers in an attempt to keep any wandering rodents out of the trailer. (So far, so good.) The (4) batteries in the office pack power the desktop computer and the mission-critical entertainment system that offers moving picture amusement each evening, and the vast majority of them are talkies! It also recharges the Evelo e-bike’s battery, which is no easy task. At times like this, I’m glad I got a spare for it so that I can still get around in the manner to which I am accustomed. Lastly, there is also a single battery and panel dedicated to running a CPAP device, which battery is now doing double duty to desulphate someone’s old AGM battery to bring it back to life.
This is a pretty decent test period for the house batteries and especially the office pack, which I sized to last for
two days of normal use under these conditions. Naturally, I’ve cut back use of the big desktop computer after Day One, which is a shame in this weather, since it’s the perfect time to scan a huge pile of receipts and manuals that now clog the office. I’m getting tired of saving paper, but find such things handy when I want to re-order items from whoever I originally got them from, or look up obscure references to potential campsites that are not on the Net, or look up service records for the Mighty Furd. What was the odometer on that last oil change? New Mexico and Nevada offer very nice tourist, fishing and/or camping booklets, but who can store them in an easily-accessible way?
Anyhow, my alleged moral outrage toward gas generators lends no room for emergency backup, so solar is it for me. As long as I can preserve my fresh foods, post mindless drivel like this on the blog now and then, and watch a movie or read a book, that’s all I really need. But 4-1/2 days and more without a decent recharge is kinda pushing it, as well as being tough on the batteries. Sitting around discharged isn’t good for them. But we’ll soldier on somehow. 🙂 Wouldn’t it be marvelous if trimming back electrical usage was the biggest problem we’d ever have to face? I’m biking to town now to pick up a small shipment before more rain sets in, so wherever you are, I hope you have a day that suits your fancy.
Strolling Amok 
I assume it’s not feasible to simply run the Ford motor for a bit to fill in the gap? It sounds too simple to be a usable solution somehow.
That’s too easy, Rod! Yup, it would certainly work for the house batteries due to their open access, but you’d have to put a gun to my head to do it in anything less than an emergency, where the voltage drop risked damage. That’s because it would take a long run time to do anything meaningful, and the Ford diesel (Navistar) of my year does not do well under prolonged idling. Its design is biased for hard, long runs, and pooping along at idle cools it down below the temps it needs to stay healthy. You eventually pay for a lot more than the fuel cost for doing it, and I can’t afford that.
I can link up packs if need be. If worst came to worst, I’d rather find another camper with a 12V output on his generator and pay to borrow it using his gasoline, and you know THAT ain’t gonna happen! Fortunately, so far, everything is holding its own. I only blogged about it because this will be the longest true sunless run since I started out, so I’m in unknown territory. It’s a technical mini-adventure.
Thanks for the school’n!
Always glad to share my ignorance, Rod!
Too many rainy/overcast/cloudy days in a row is what made me leave my last long term site. Even going for a drive only brought my batteries back up to 87% and that didn’t feel like enough. It was almost enough to make me think about getting a generator. Not quite enough, though. 🙂
Yes Linda, the only thing wrong with solar is that it eventually requires the sun to be hanging out there. You’d have to really drive to get out from under a general overcast! Automotive alternators are an unhappy way to recharge large-capacity batteries, not being really built for that. And that lack of a full, soaking charge will sulphate them faster (as will the lack of any charge at all). The only real solution for this kind of weather is adding panels and/or battery capacity, which I won’t do because this is only an occasional issue. I can trim back my luxo-lifestyle as needed – there’s always some chore that awaits which doesn’t use any electrical power to do, which explains my whining when the sun goes away.
My CPAP system is the only one biased toward charging no matter what, with a big 195 watt panel attached to only one 105Ah battery, twice the panel-to-battery ratio of any other system I have. (I take my sleep very seriously, I guess!) So compared to the others, it doesn’t particularly care about dark overcast skies, because the battery is also too big for what it does and is recharged faster than the others. No stress.
Technically, I can simply step outside and take a minute to reconnect wires in a way to put three of the four panels toward the office pack, but that’s the least important system, and I only do that when I’m rolling hot and heavy over a long day at the desktop. As long as I bunk out here in the sunny Southwest, a generator isn’t going to happen for me: no space for the generator and its fuel storage, and no desire to fool with one more engine-powered device that lacks any fun factor at all. Been there, done that!
Hey Doug I need some of your wonderful engineering knowledge and advice? Susan and I just got a nice solar system. What is desulphating the batteries and how often do you do it. I have a fancy PMMT hmm er PVVT whatever Controller. It says something in the manual about a 2 hr thing you can set it to do auto or manually. Also how often do you check the water? I have 6 volt Trojan golf cart batteries, 4 of them. Thanks pardner!
That’s MPPT, and I can give you all the answers you need, Bill, as long as you don’t care that they aren’t the RIGHT answers. I’ve been going past your camp but so far have not found your pickup to be there. I’ll continue to try to catch you before I depart later this month, and give you all the bad advice I can.
Doug, I have been watching my meter and it hit its all time low, but shot up pretty quick today.
I did not realize how many low sun days in a row we just got through, glad it’s over.
Got to publicly say how impressed I am with your EVELO electric bike…….anyone looking to get an electric bike needs to look at them and get ahold of Doug for a discount!!!!!!
Yep, it was a trial, but all you need is one decent day to recharge them fully. Maybe I should post about minimizing sulphation in deep cycle batteries, since that’s what kills them, and they are too expensive to ignore.
Yes, the Evelo is a workhorse, I must say. Very adaptable. Actually Papa, anyone can get $100 bucks off list price any Evelo model by using “StrollingAmok” as a discount code. They periodically have sales that discount even more than that, but it doesn’t hurt to use the code as baseline insurance. Before long, I will be an “Evelo Ambassador”, which means two things: one, I’ll be the only really bad decision the company has made so far, and two, I’ll get a few bucks from them for anyone who uses that discount code to purchase an Evelo e-bike. I suppose I should eventually post about it, since I’ve harped on my Aurora, but each model suits different purposes even though they all share the same mid-drive motor setup. Each model has its own strong points for usage. One of them isn’t even an e-bike, but is a front wheel conversion that carries its motor and 8Ah battery inside, yet operates as a pedal assist drive! And the price is right.