Sirisian t1_jdz1i7x wrote on March 28, 2023 at 6:03 AM

Reply to comment by Particular-Lake5856 in German manufacturer achieves 80% overall efficiency with new PVT solar module by galileofan

Interesting. So if you had a bunch of these and used like a 35% efficient steam turbine without any other losses in the piping that's 20% + 35% * 60% = 41%. That seems extremely high though, so it seems wrong to me. That would match some of the most expensive solar panels used for satellites.

JeremiahBoogle t1_jdz57nt wrote on March 28, 2023 at 6:52 AM

I think it would be meant for solar water heating in the house, it won't be hot enough to drive a steam turbine.

No_Opposite_4334 t1_jdzjlw4 wrote on March 28, 2023 at 10:21 AM

What if a liquid (e.g. acetone) with a lower boiling point (57C for acetone) is used?

RedditorsArGrb t1_jdzlqn9 wrote on March 28, 2023 at 10:48 AM

small temperature gradient means low efficiency in a heat engine. See: https://en.wikipedia.org/wiki/Carnot_cycle#The_Carnot_cycle

A "35% efficient steam [system]" is not a physical reality here.

SandAndAlum t1_je4owx4 wrote on March 29, 2023 at 12:09 PM

Working at a high enough temperature to make an efficient heat engine run would almost certainly make the PV performance worse or destroy it.

This will be low grade heat for space or water heating. Possibly applicable to chemic process or electrolysis too (heat can reduce the electricity needed to just splitting the molecule). Might be able to use the electricity to upgrade the heat using a heat pump for chemical use, although you're unlikely to beat a heliostat which is much simpler.