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Crashley

(101)

I find this discussion very interesting. To my knowledge, NO ONE in the media mentions that it takes lots of energy to produce solar panels, or even attempts to say how long they must produce energy to break even.

I think it still makes sense to manufacture, use, and improve them as eventually the energy to produce them could come from PV and other renewable sources. I was surprised to see how long this discussion has been going on. Good work.

PS: I've been in the satellite business for almost 35 years and PV and batteries are the only way to go for a 15+ year lifetime. Talk about off the grid.

Crashley

(102)

A 12kW triple junction GaAs solar array in space produces about 1.5 GWh in 15 years. How many Wh do you think it took to produce it? (I don't know) Obviously it does not offset any terrestrial energy production since there is no other way to get power to the satellite

I realize this is not really relevant to the discussion, but I am curious.

By the way, the "scorecard" site did not seem to address how many Wh it takes to produce a W of solar panel output. Or maybe I missed it.

Jamey Johnston

(103)

Seem like there is a scholarly / engineering disagreement, hmm?

https://energy.stanford.edu/news/PV-industry-likely-net-energy-producer

pam

(104)

know-it-all rants by Devry tech grads like dana are really impressive...

Slowburn

(105)

Photo-voltaic is the wrong way to harvest solar energy. Use solar water heaters to drive absorption heat pumps, and Stirling cycle engines. Expand the ammonia through modified water cool ICE so that as well as generating the mechanical energy you get to keep the cool for food preservation, air-conditioning, & and water harvesting. This also give inherent energy storage as you do not release the anhydrous Ammonia to the engine until you need the power whether to directly drive a machinery or generate electricity.
Don't forget to harvest the waste heat from the heat pump's condenser.

Wouter Carrette

(106)

Did anyone even figure in the transportation CO2 footprint?
As most panels are produced in China, they still need to be moved to the rooftops in Europe/the US. How about that?

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