Detox John said:

Solar Power is so cool. it is clean and renewable energy. when the cost of solar panels goes down, i think every home should be owning a mini solar power station.

From what I’ve seen of solar power in practice and considering that no country has gotten even remotely close to 1% total electricity from solar, I don’t think it has any future even if solar cells were dirt cheap. the inherent limitations make me believe that even if the solar cells were virtually free, it would still hardly be worth the cost of the voltage regulators, inverters, copper wiring, mounting clips and other incidentals that it would involve. PV has consistently proven to be absolutely incapable of providing any kind of reliable power on the megawatt level with even remote economy (at least on earth).

I’m not saying it doesn’t do well in some applications like calculators or seismometers or weather stations or whatever, but when you’re talking megawatts – NO WAY. Much less gigawatts. Anything that can’t be scaled to produce many gigawatts is not a contender for any major function in the energy grid.

        Detox John said:

Solar Power is so cool. it is clean and renewable energy. when the cost of solar panels goes down, i think every home should be owning a mini solar power station.

Dream on! For decades, there have been delirious proclamations that the world would soon run on solar energy. Those statements have always sounded too good to be true and, sure enough, they have always been false. The laws of physics impose certain inescapable shortcomings on every solar-related energy source.

Space mining though hasn’t been proven as of yet so we only have guesses about the economics of it.

I hear the whole idea of mining and fabricating stuff in space. That’s all fine, but it will be a while before we can really consider having production factories to make goods on the moon or asteroids. It just needs to much to build stuff. Think about a modern rocket and imagine how many factories and workers worked on that, if you think of every transistor and circuit board and pump and nut and bolt.

As for transparent solar cells, what I’ve heard is that they’ll only be partially transparent and so might capture 50% or so of the light and let the other 50% through (i.e. tinted windows that also generate some electricity). Whether they’ll be worth it is another matter but I wouldn’t call the idea impossible.

        Luke Weston said:

Have any of you heard about the recent Japanese proposal to build a space-based photovoltaic energy satellite, on the 1 GW scale? What a huge waste of money.

Eh. It won’t be a waste of money because it’ll never happen. They’d need thousands of rockets, even if each were the size of the largest realistic rockets conceived.

The only money that will be lost will be on stupid concept study work and such things, since it will never actually happen.

Have any of you heard about the recent Japanese proposal to build a space-based photovoltaic energy satellite, on the 1 GW scale? What a huge waste of money.

I recently had someone try and tell me that transparent photovoltaic windows were a great idea… except, well, you can’t have your light and eat it too, so to speak. The light either goes into lighting up the building or it gets absorbed in the cell; it can’t do both.

        Daniel said:

Two points that I have not seen made yet:

- I’ve heard that solar cells actually take more energy to make than they usually generate in their lifetime

It depends how you do the calculations, but it seems that they are better than break-even at this point, but not by much.

No there are none. The environment is not favorable. To make it so, the road’s primary task – that of providing a running surface for vehicular traffic – would be compromised. The expense of such a system optimized for both tasks would far outweigh the value of the power generated.

Some work has been done on savaging solar heat from large paved areas, but that too, while somewhat less complex and expensive, does not show much promise for general deployment.

- I’ve heard that solar cells actually take more energy to make than they usually generate in their lifetime

- Is there any advantage to embedding solar cells in a roadway compared to rooftops or other locations? I see lots of discussion of the problems associated with putting them in the roadway, but are there any BENEFITS at all to even consider overcoming the problems?