Research Promises Full-Spectrum Solar Cell

nphillips writes "As is being here reported here, a serendipitous discovery was made that a single system of alloys incorporating indium, gallium, and nitrogen can convert virtually the full spectrum of sunlight -- from the near infrared to the far ultraviolet -- to electrical current. For if solar cells can be made with this alloy, they promise to be rugged, relatively inexpensive -- and the most efficient ever created. Solar cells so efficient and so relatively cheap could revolutionize the use of solar power not just in space but on Earth."

Comments

Re:UV during nighttime...

[Christopher Thomas]

As I understand it, UV light hits the earth at all hours.

Does anyone know how much UV hits the earth during the night?

Almost none. Virtually all of the light that strikes Earth comes from the sun.

As another poster pointed out, you may be confusing this with the mid-IR glow that warm objects (including the ground and the air) give off. The amounts of energy involved are very low, and room-temperature thermal IR is difficult to convert to electricity efficiently.

Any solar power scheme (and so any photovoltaic scheme) has to have enough storage capacity to power the load overnight. Ideally, it should be able to provide power for several days, in case of cloud cover/rain/whatever. This is why most home-powering schemes involve large battery arrays. A city-powering solar plant would probably use fuel cells (energy density is much higher, and there are off-the-shelf models of power-plant scale already available and in use).

Re:Orbital Manufacture - REALITY CHECK

[0x69]

The article noted that current-best solar cells are about 25% efficient, vs. 30% max. theoretical. How many percent more efficient are you figuring on the new solar cells being if space-made (vs. Earth-made)?

Check out the $billions$ that the dinky space station costs just to keep up. Ditto launch costs for your raw materials & totally unproven zero-grav solar cell factory equipment.

Now spread the extra costs of space-made solar cells out over the number of cells that you think will actually pass QC & reentry. Where do you see the high-volume market willing to pay the $HUGE$ price premium for a few percent better efficiency?

As gbell notes further down, efficiency doesn't mean too much, especially competing against fossil fuels. Cost per watt (call it financial efficiency) is what really matters.