Do PVs with a load run cooler than without it?

[GeorgeOfTheJungle]

Imagine a one square meter totally black matte PV with 100% efficiency receiving 1kW/m2 radiation from the sun. If it has no load connected all that energy (1000 joules/s) turns into heat and raises its temperature. Now you connect a 1kW load 10 meters away and instead of heat you'd be pumping all that energy to the load and... the PV won't heat up.

Does that sound about right?

In the real world the efficiency is ~20% max, but if the same principles apply it should be cooler if fully loaded than if not?

[GeorgeOfTheJungle]

Yes.

Ok, good... that's what I was saying yesterday in this thread https://www.eevblog.com/forum/chat/crazy-claims-made-by-electronicselectrical-salesmen/msg1411459/#msg1411459 when you told me "Are you on some good stuff?"

[GeorgeOfTheJungle]

Modulo the hyperboles, as in "save that PV energy into batteries, a zillion powerwalls, climate change solved", the principle of "capture the sun's energy (somehow) don't let it turn into heat" is sound, isn't it?

We are burning enormous amounts of fuel to turn 20..40% of its energy into useful work and in the process we release 60..80% as waste, useless heat, if we instead got all that work from the sun: 1) we would be removing that heat from the surface of the earth and turning it into useful work instead and 2) we would not be releasing that 60..80% of waste, useless heat.

[NiHaoMike]

Your problem was that you can't just store solar heat in batteries. For every 1J you store, you probably need 1MJ to make the battery, so from this perspective, this is a very inefficient way to store energy in geological scale.

1kWh of lithium batteries go for around $200 nowadays and $200 worth of electricity at commercial rates is only about 5000kWh. In reality, the raw materials are the majority of the cost so the actual factor would be much less than that.

The point that there are cheaper ways to manage energy for a lot of applications still stands.