Solar Power Play

dpilgrim writes "While American power companies continue to chase vanishing oil reserves, the Japanese are once again a step ahead in innovation. Reuters is carrying this story about Sharp's new manucfacturing plant in the U.S. Sharp will begin manufacturing solar batteries stateside, and expects more than half its solar battery sales to be in the U.S. by 2004. Looks like a good use for that south-facing hillside on my property."

Comments

Step in the right direction, but...

[Smidge204]

Photovoltaic systems still have a long way to go to become economical enough to compete with more conventional methods.

You get about 100 watts of solar radiation per square foot (perpendicular to the sun's rays). Current commercial PV cells are, at best, 15% efficient.. so now you have 15 watts of electricity per square foot.

A conventional powerplants generate roughly 500-1000 Megawatts each. Doing the math, you'ld need well over 32 million square feet of collection area to match that... roughly 765 acres of active surface. PV arrays can't be packed together either, because they would cast shadows on eachother... so the actual real-estate required would be 4 or 5 times that!

Even if the PV cells were *free*, the cost of installation, service, and the land itself would be astronomical! There's no way a solar farm could pay for itself.

Nobody is going to stop burning coal and oil anytime soon (unless they run out!)

Not to say PV cells don't have their uses, of course. Cheap PV panels can certaintly help ease the energy budget!
=Smidge=

Re:Step in the right direction, but...

[bcboy]

I disagree, for two reasons. First, as everyone does, you're only looking at the supply side. In fact, we waste astronomical amounts of power, and talking about any energy source is rather silly before fixing our technology on the demand side.

Second, cheap PV would be financially attractive to the home owner. You don't need dedicated land except for high density housing and industrial demands. The main blocking issue for roof-top PV is not efficiency, but cost. We can get about 15% efficiency, but only at great cost. Very cheap, very low efficiency PV is currently running around 1% efficient. Some claim you need about 5% to be viable. I think this is high, at least for some markets. 3% could power a California home (mild climate) if demand-side leaks have been fixed.

It seems likely that the low-end designs will improve efficiency before the high-efficiency designs can bring their manufacturing costs down significantly.

Re:Step in the right direction, but...

[lommer]

The key to bring photovoltaic cells into practical use is how you phase them in. Obviously, noone is going to fund a 756-acre power plant, but If you provide incentives for homeowners to build PV systems into their roofs, then the technology can slowly phase in.

This approach would work well in sunny climes like California, but the key is allowing the PV cells to plug directly into the grid. i.e: when the PV cells are producing more power than the home needs, they put power into the grid, when the home needs more power than the PV cells can provide, it sucks some off of the grid. The utility could then meter all of this and give people discounts on their electricity bill based on how much they contributed into the grid. With cheap PV cells this could become a reality, and there is an enourmous amount of area on rooftops in cities. Though the power provided by such a system would not really add up to much in the winter, it could make a BIG dent in power consumption in the winter.

Re:Solar Power discussion.

[Smidge204]

1) Cost.

2) Energy already travels from the sun to earth at the speed of light. You're not going to get it here any faster. Electromagnetic radiation travels through space without loss (save for interference from objects and gravity fields).

3) What if the beam of highly concentrated energy misses the near-earth target?

4) Where are you going to PUT the near-earth target?

5) Everything we use for energy today exists because of the sun (except for nuclear, anyways, but that's leftovers from some other star), so basically we're running on locally stored solar energy...

=Smidge=

Re:capital cost

[zogger]

--there are many finance outfits that will include a solar or hybrid system directly into your mortgage now. BTW, it's neither new nor untested tech, it works perfectly normal and predictably. there are hundreds of thousands of homes in the US that have part or full solar power now. The largest financier I'm aware of is GMAC but I'm sure there's others. Spread out over a 20 year note is just not that bad I guess, say if you are already buying a -pick a number- a 150 grand house. Look for a 140 grand house and add the solar to it right off the bat. My guess is you could "struggle by" in the 140 grand house about the same as the 150.

Here's one of many ways to get it to be less costly, building your home, do two things, make it superinsulated,do some research on how to be more efficient in heating and cooling, save a buncha cash there monthly, and site it on land that is far away from utilities. All it needs to be is one mile away, usually enough to drop the per acre cost tremendously. In most cases the cheaper cost of the land will be reduced enough to make it a break even with closer in land when you add in the solar or whatever hybrid system you want. I'm a fan of the hybrid systems BTW whenever applicable.

We live on solar, works great, the best part is it's paid off, and works no matter what happens in the energy markets or with political shenanigans or like wars in the mideast whatnot., etc. No surprises. You can't get that with an electrico account, you are on a month to month, no guarantees it won't cost ten times as much ten years from now. During 2000 people all over the country saw their bills double, just like that, and they had to eat it then and ever since. No one would put up with that on their car note or house note, but for some reason they will put up with it when it comes to delivered electricity or city gas. It's a weird way to buy something if ya ask me, but to each their own, I did it for decades, glad I don't anymore, wish I had done this sooner. I don't like "renting" many things, and to me my energy if possible I want to own. Same as computers, wish I had bought my first one sooner. I'm not aware of any place joe residential home owner can get a ten year price guarantee carved in stone contract on delivered grid juice. If there is anyplace that offers such a contract I'd like to see it.

Solar and battery bank storage is a heckuva nifty UPS as well. Try days (maybe) of storage, even with little sun, that is still clean, instead of 15 minutes to an hour with a typical ups unit.

The other point on solar(or wind, hydro, steam unit, etc) is it doesn't in any manner require you to be either/or, this I notice is some sort of fantasy I read detractors say, that you have to be "OR" with this, you can have BOTH normal grid provided and solar if you choose. You can start small, work your way up as your interest and finances dictate if you want to go that route. You can technically start at one grand and do it. One grand is enough for a big panel or two, a charge controller, some batts and a small inverter. That's just an example. Just having enough for say one commonly used circuit in your home, say as the power and UPS unit, to run your home computer off of, is nifty.

With that said I'm unsure what they mean by a "solar battery" in the article. PV's are more correctly identified as a "generator" by function. Your battery storage is a separate deal, they are called "batteries". Maybe they are talking about those little combo cellphone batt/pv panel units. I don't know.

Journalists, gotta love 'em..... they try hard, forced to be tech experts in everything to write about it for general consumption, wind up being experts in not about much.

Re:Lower prices?

[aaarrrgggh]

My guess is that they are referring to a 3kW cell array. The ROI would be primarily a factor of how much power you use during daylight hours.

Without the tax incentives, it would be hard to see a 10-year simple payback, unless there are significant costs associated with hooking up to the power grid (namely distance).

Compared to a 3kW diesel generator... it has an ROI. Compared to $0.10/kWh... not yet!