Thread: Removing heat from cells

Sunlight as we get it on the surface of planet earth contains photons of different energy, mainly from infra red (lower), then red to violet, and of course ultra violet (highest). IR just heats stuff up, visible ones help you see, grow plants, and UV wrecks molecules (causing plastic to rot, skin cancer etc.)

Solar panels usually need photons more energetic than red, more like green and blue. Trouble is, any filter that removes lower energy photons (infra red, red) probably blocks some useful ones too. So the best bet is to let the whole shebang fall on your panel, then cool your panel by another means.

I read a post somewhere by a person in the tropics who runs his sprinkler on his panels and gets 20% more power. A good stiff breeze over the panels helps too. So mounting them flat to a hot tin roof is not the best way really. I have mine on a post with a solar tracker, up in the breeze above the house.

sort of like pumping the air from the gap of a double glaze window into a heat pump to transfer the heat to water?

Originally Posted by Blknight.aus

sort of like pumping the air from the gap of a double glaze window into a heat pump to transfer the heat to water?

Great idea! Maybe you can get a gov't grant to promote it, like Firepower.

Seriously, $100 to increase the power output of a typical solar panel by 20% would be better spent on a 20% bigger solar panel, methinks.

not really no.

increasing energy density is the name of the game...

any one can make more power by making it bigger. just look at any yank vehicle they cant build with finesse so they just muscle it up in size.

Good point. Given a limited area I would spend money on a more efficient panel of the same size, hence more power. Otherwise what counts is dollars per watt of useful output. There are many people working on new technology, such as Sliver cells, I can hardly wait for the new stuff to come out.

Until you have the available space covered with collectors, the major concern is cost per watt, not efficiency, with durability as well probably more important. While there are a few applications where the available area is fully used, these would be a very small minority.

Note however that many ways of increasing efficiency will also reduce the cost per watt - for example anything that gets more power from the same amount of crystalline silicon is likely to reduce cost per watt as well as increase the efficiency - but it is the lower cost per watt that makes the panel more desirable, not the increased efficiency.

John

while thats a fair and valid point if people werent chasing a greater energy density by now we'd all be driving v32 7:1 compression engined vehicles just so we had the ponies on tap to go faster.

have a vague once over on the price drops in various power providing sources batteries, solar panels, wind generators the whole lot. Almost invariabley after a breakthrough that ups the energy density of the suppling item the older stuff of that type becomes cheaper once the new tech pokes its nose into the market. IMHO a good thing because your watts per dollar goes up

Originally Posted by Blknight.aus

while thats a fair and valid point if people werent chasing a greater energy density by now we'd all be driving v32 7:1 compression engined vehicles just so we had the ponies on tap to go faster.
.............

A slight difference between a fixed installation and a vehicle - again, the quest in vehicles is not volumetric efficiency, but power/weight and fuel efficiency plus other less obvious considerations such as initial cost, reliability, durability, driveability, maintainability, exhaust emissions; in other words, no simple measure. Same with solar panels, but I suggest that for these cost per watt is a single factor that is more important than any single factor in designing a vehicle engine.

John