Innovative Use of Plastics Could Cheaply Double Solar Cell Output

doug141 writes "In standard solar cells, much energy is lost (as heat) from photons mismatched to the capability of silicon to capture them. A new technique uses a pentacene layer to down-convert each hot (un-captureable) electron to two electrons that can be captured by standard silicon cells." You can read more at the University of Texas research group's web page.

Comments

Power companies

[bonch]

It would be really interesting to see what happened if solar energy became affordable enough to power people's homes. Based on current technology, the cost of solar panels is several thousands of dollars for a typical home's electricity needs. Over the lifetime of the panels, that's about 30 cents per kilowatt hour, which is three times the cost of typical utility fees. I wonder if there would be resistance from power companies if people were able to put cheap solar panels on their houses, or if they would buy up all the patents so you had to buy your panels from them.

Re:Power companies

[russotto]

I wonder if there would be resistance from power companies if people were able to put cheap solar panels on their houses, or if they would buy up all the patents so you had to buy your panels from them.

They'd just institute daylight-based pricing. Use of electricity during the day = $0.05/kWh. Use of electricity an night = $0.50/kWh. Now you've got to solve the battery problem AND the solar panel problem.

Re:Power companies

[tomhudson]

The power companies won't mind if solar is used for large-draw things like daytime AC, when they themselves have to buy power at peak rates. They'd actually become more profitable with less demand.

The use for night-time heating is a solved problem - store the heat in something massive during daytime hours - you don't even need to take the losses from converting to electricity and back.

Re:Power companies

[Oxford_Comma_Lover]

Three times the cost of typical, maybe, but it still makes sense in certain places.

Hawaii, for example, has a typical 30c rate. The bigger issue is that most of the locals can't afford the capital to do the installation in the first place.

Re:Power companies

[fyngyrz]

They'd just institute daylight-based pricing. Use of electricity during the day = $0.05/kWh. Use of electricity an night = $0.50/kWh. Now you've got to solve the battery problem AND the solar panel problem.

Nah, then all you need is batteries and a charging and inverter system. No solar panels at all. Because all you'd have to do is store electricity from the company during the day, and use it at night or when the power is down. Right now, there's no great price advantage to doing this, but the second the day and night prices diverge significantly, there would be. And THEN, if they caught on and changed it back, all you'd need to add would be panels. So this would be a very bad move for the power companies.

Re:Power companies

[CarlDenny]

That's an insanely ignorant suggestion.

That would incentivize people to move their power usage from off-peak times to on-peak times, forcing power companies to build *more* capacity for on-peak utilization. The pricing you describe is the *exact opposite* of the actual economy of the power industry, and any company that tried it would end up out of business.

The fact that solar only generates during the day makes is a boon for power companies, it prevents them from having to build expensive plants for peak production while leaving lots of profits in providing baseline power with existing investments.

Re:Power companies

[kkwst2]

Now many states have have laws requiring essentially that the power company buy or give you credit for anything you produce. So you get the panels installed and apply for a two way meter from the electric company. They keep track of how much you produce and subtract it off your consumption essentially.

Furthermore, some states require utility companies to use so much power from solar, and this is done essentially by buying credits from people making solar. So in NJ if I have 10 kW worth of panels I might generate enough credits in a year to sell for $6000. It is essentially the state dictating that the power company has to pay me money for making solar energy. That is on top of the savings you get from using less electricity.

So with federal rebates, a 10 kw system costs around $35k to $40k to install. But with the credits and electricity savings, it will "pay for itself" in 5 years or so.

In NJ this fell apart a little bit because everyone saw it was a good deal and there is now an oversupply of these credits, so the value of the credits are less than half of what they were last year. Time will tell how it all shakes out. If I got no money for the credits, the panels should pay for themselves in 20 years. So it will be somewhere between a ton of free money and a marginal investment.

Re:Power companies

[Lumpy]

It already is. I can buy 5KW worth of solar for under $30,000. coupled with changing energy consumption to reasonable levels and having a home that is not a giant screen door for heat like most american homes, one can spend the price of a single mid sized car to go off the grid.

$30K is dirt cheap for that (complete with intertie inverter and battery storage) Most new homes built waste more on marble countertops and other stupidity like too large of a sq footage.

A reasonable sized 1500 sq foot home built by an archetict that actually knows what he/she is doing can be 100% solar with heat and electric in a climate as far north as 45deg latitude and cost the same as a current stupid sized house.

It's already there, Problem is people prefer 3 car garages, 5 bedrooms, 2900 sq foot with cathedral ceilings, marble counters and giant front yards to sane sized homes that are at least energy star in insulation and with near zero costs for Heat, AC and electricity.

Improving solar cells

[JohnWiney]

Slashdot seems to post a lot of stories about improved solar cells, but solar cells never seem to improve.

Re:Improving solar cells

[vadim_t]

Sure they do.

There are two problems though:

1. That somebody in a lab figured out a way to make a cell 15% more efficient doesn't mean it's going to be manufactured tomorrow.

2. 15% more efficient means "15% more efficient than what we started with". This means "We took a cell that coverts 15% of the Sun's energy into electricity and made it covert 17.5%", not 30% as people seem to expect.

Re:Improving solar cells

[Waffle Iron]

Slashdot seems to post a lot of stories about improved solar cells, but solar cells never seem to improve.

True, but only if you define a double-digit percentage drop in unit price every year as "not improving".