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Let the sun shine

Well this may not be very automotive related (unless you have an electric rechargeable auto) but this is general discussion and there are alot of smart people on this forum that are capable of thinking outside of the box.My question is, as a fan of solar generated electricity(PV cells) can anyone come up with a better way of storing excess solar power(electricity) then chemical accumulators?(batteries)-Kevin

Batteries seem to be where the action is in energy storage. Better energy density is what the researchers are working on. It takes time to develop and test new systems,and finally full scale production. As hybrid and electric vehicles become more prevalent, more researchers will earn their money from this work. Electrons are too reactive to store on their own unless you use some sort of magnetic can, and then the energy requirements would be high.

There’s at least one way I know of that is being worked on today.

Applying an electrical charge (generated from the solar panels) to water will release the oxygen hydrogen bond. The hydrogen is then collected and used later for a power cell.

It used not to look like batteries were affordable on that scale, but that isn’t looking like such an obstacle as it used to. Ideas I’ve read of include pumping water uphill (from one reservoir to another), underground pressure in old mines, and heated liquids stored in insulated reservoirs. Solar thermal plants already do the last, but it’s not a big expense for them since their collectors have to heat fluids anyway (usually molten salt.)

Thanks Guys, Mark M,I live about 12 miles from the worlds largest pumped storage facility-so I had this idea about pumping water uphill,I was kind of hoping someone would break it down for me.I really hate to think till my head hurts now,considering all the details a rocket scientist would be a good person to whip up a schematic diagram for a mini pumped storage( penstock size,mini turbine size,valving,pond size,difference in elevation between upper and lower resivors, etc; -Kevin

Ouch, all that detail makes my head hurt, too, Kevin. I’m in California, where we have quite a few biggish reservoirs upstream from others. Also plenty of sunshine and people. But I don’t expect to see it happen much.

Yes Mark,I dont think many people will go for things like that.My wife showed me a guy(a retired airline pilot) who is totally off the grid,he powers two large houses with solar.Didnt get a chance to look at his system,the real interesting part would have been his storage system.I believe if more people would make this thier hobby we would see more solar collectors around.Gradually more things are becoming availible,there is a small affordable solar powered deep freeze on the market now for example-Kevin

My wife showed me a guy(a retired airline pilot) who is totally off the grid,he powers two large houses with solar.Didnt get a chance to look at his system,the real interesting part would have been his storage system.

He might use regular lead/acid car batteries wired together.

I saw on TV once, a house with an off-the-grid electrical system, although I think it used wind, not solar, at the time. They had a large area with car batteries wired together that would run their appliances when there was no wind. I don’t know if they were wired in series or in parallel. I think if you wire them in parallel, they all have to be the same voltage batteries. It’s probably safer to wire them in series, although someone more knowledgeable should probably weigh in.

If you’re not using them in an electric or hybrid car, regular lead/acid car batteries work pretty well. The main reason we don’t use regular lead/acid car batteries in electrical cars and hybrids is the weight. If you were to use them on a household system to store DC, the weight would be less of an issue. The only issue might be running AC (alternative current) appliances on DC (direct current) power. Inverters (which convert DC to AC), aren’t very efficient. You’d be better off getting DC appliances.

It’s cheaper to put the PV arrays in good (sunny) areas and wire them directly into the grid. There, sunny= hot= air conditioning, so the supply tracks the demand. This is unlike wind power, where high winds are often seen in spring and fall, when electrical needs are lower.

 Build a pond up hill so you can pump water into the pond and refill it with a solar powered pump.  Depending on where you are a windmill may be a better choice

well that would be a hybrid system of sorts, sometimes I think a person should rethink the power priorities too.A person basically needs lights,refrigeration and hot water,of these three I would think refrigeration would be the hardest(whoops forgot running water) hotwater wouldnt be that hard solar collecters work well,led lighting with small storage batteries would be feasible,running water would be pretty easy with a small pump and a gravity resivor,a small radio system would be cheap and easy-But pretty much forget 20 KW on demand and a lot of luxurys-but this is deviating from the original post a bit-Kevin