Solar Cells Get Boost

An anonymous reader writes "Researchers from Los Alamos National Laboratory have tapped the efficiencies of nanotechnology to double solar cells' potential energy production. The key to the method is the use of lead selenium nanocrystals which can produce 2 electrons where 1 was produced before. Other optical applications can also benefit."

Comments

Electrons are not "produced" by solar cells

[I_Love_Pocky!]

Solar cells harness engergy by absorbing photons, which cause electrons in an atom (which are already there) to move to a higher energy state. This technique moves two electrons per photon, rather than one. The point I am making is simply that electrons are being moved, and not created. That would have amazingly different implications, as that would be creating matter from the energy in a single photon, which would only work with very high energy photons.

The holy grail of solar power

[n1ywb]

This is it folks, this is what we've been waiting for. As it is, solar panels are a pretty marginal energy source for most applications. We've all seen the specially built vehicles that are basicly a big solar panel on wheels (some of us (like me) have even built one). We've all seen the houses with the roof covered in solar panels and they still have to buy all whacky expensive 12v high efficiency appliances and forget about an electric drier. With solar cells like these, solar power just lept from impractical to practical. Make way for the days of solar powered PDAs and cell phones, cars, houses, buses, airplanes, you name it. This is the breakthrough that will lead the way. Unless it flops, of course.

Re:Will this work with other materials?

[Intrigued]

I simply don't know enough about the physics, but... can this be applied with the other developments like multi-band gap improvements? (New Material for More Efficient Solar Cells) I know that these use different materials but can the same principles be applied?

If so, it should multiply efficiency. I would love to see multi-band gap using 2-3 times wider percentage of the light to move multiple electrons. You should be able to pull 80%+ efficiency if that is possible.

Someone contribute some understanding on the physics please.

Storage Storage Storage

[tino_sup]

Renewable energy has made phenomenal leaps, but the storage restriction is the crux. Efficiency is great, and is a move in the right direction. What remanins is the development of efficient and economical storage devices. Imagine your car operating for a week on a one hour solar charge stored in a device the size of 4 D sized batteries.

No it's not.

[Spamalamadingdong]

The real issue with solar energy isn't watts/m^2 of panel, but watts/$. We have more than enough square footage to power our houses and businesses even at current efficiencies, but the capacity is still so expensive that it is very marginal. If Pb/Se nanodots can be made more cheaply than the same wattage of silicon, we'll be ahead; otherwise we won't be.

If we get really lucky, this technology will work well at high light flux and high temperatures (~100 C). This would allow use of concentrating collectors and use of the waste heat for space heat and domestic hot water, multiplying the benefit of the collector and making the whole affair much more economical. Imagine a house that powers its own appliances, stores enough hot water for several days of hot showers and its own heating load, and on sunny days has plenty of juice left over to feed to electric cars. This house would be almost completely independent of fossil fuels and offset fuel use elsewhere, and I'll bet that we could build it now if cost was no object - if we can get 50% or even 40% efficient solar cells at $2/watt working at 100 C, we'll be there.

Storage can be TOO good

[Spamalamadingdong]

Imagine your car operating for a week on a one hour solar charge stored in a device the size of 4 D sized batteries.

Let's see, if you drive 250 miles a week and get 25 MPG, that's 10 gallons of gasoline or about 60 pounds. Gasoline has about 9 times the energy of combustion as TNT (because TNT carries its own oxygen). So: Imagine the energy of several hundred pounds of high explosive in a device the size of 4 D-size batteries. Not so appealing any more, is it?