russ_watters said:
There isn't any way around this problem; it is inherent to the fact that solar power is only produced during the day.
By "this problem" you mean storage. Yes, wind and solar won't go anywhere unless the storage problem is solved. In my mind it is the sort of problem that is eminently solvable.
You like nuclear, but, in my mind, nuclear is doomed based on what you said in another thread a year or two ago, which was that we only have 50 years of nuclear fuel left at the current rate of usage. Breeder reactors would extend that by a fantastic 100x, but no one seems to be seriously working on that for some reason. You said that the future of nuclear depends on how the fuel we have is used in the next 50 years: once they run it through a conventional reactor it is unsuitable for any other use. If there isn't, right now, a serious effort to convert to breeder reactors, what is the point to putting any eggs in the nuclear basket?
russ_watters said:
That's a lot of "if" that assumes the economic viability of the idea instead of investigating it. The inefficiency problem was already mentioned, but the storage problem I discussed above is additional.
When you start out on something that hasn't been done before, you first explore if it can be done with what's already available. If it can't, then you start asking what you need to make it viable. New systems don't spring to life fully formed: there are always apparently insurmountable problems to overcome. Blah, blah, blah: you know this already.
This hypothetical company would be much better off selling the solar power to the grid during the day (when it can get more for it) and buying coal or nuclear power at night (when it is practically free) to make hydrogen for cars.
There are no hydrogen cars to speak of at the moment. No market there. There are, however, utilities all over the world that need fuel, and that is a very stable market.
Of course, if you use the hydrogen to replace natural gas in power plants...well, hopefully you can see the circular logic problem there: your economics would be best buying hydrogen fueled electricity at night and using it to make hydrogen to sell back to the company making the electricity...and just leaving the solar farm to directly supply the grid with electricity. Hopefully you can see that you can't turn a profit by selling back to someone a quarter of what they just sold you.
No. You buy some land and some solar panels or wind mills and you use them to take advantage of the
completely free sunlight and wind to make hydrogen which you sell to the utilities. Your expenses are the land and equipment, your employees, your taxes, etc, all the usual business expenses,
except for fuel. The whole thing is predicated on the electricity you make yourself being cheaper than what you'd buy from the utilities. How could it be cheaper? Obvious: they have to pay for fuel and you don't.
There's the additional consideration I mentioned to NTL2009 earlier that, when splitting water you use your electricity as DC directly out of the PV cell or windmill. If you sell it to the grid, you have to put it through an inverter first, which creates losses and is an additional bunch of equipment you have to pay off.
So, you are in the business of hydrogen farming, not electrical generation. Why? Because the utilities need storable fuel and the point of your business is to exploit that need. The argument, "You could make more selling electricity directly to the utilities," is pointless because you are choosing to exploit a different market (or, more accurately, a different need of the same customer). Starbucks decided to sell coffee and not liquor, despite the fact you can mark up alcoholic drinks way more than coffee. Coffee is the market they decided to exploit. You go into a business, you commit to a market and never mind worrying you could be in something else more lucrative.
However, the hydrogen farm idea is moot since it looks like they're committing (for at least ten years anyway) to the battery storage alternative. I just wanted to address those of your objections that seemed based on your not having understood the proposal.
russ_watters said:
But the problem with solar+powerwall economics is that it is backwards. The whole point of conventional energy storage is to generate energy and store it when you otherwise could only sell it cheaply because you don't need it (at night) and resell it for more money when you do need it (during the day). Or to avoid building a new power plant. Storing solar takes that and flips it over, buying high and selling low by storing energy that could be sold at its most expensive and using it or selling it at a time when the energy is cheap anyway. It's a huge money loser, not a winner.
Don't know where you're getting these ideas. According to the article I linked to above:
Once in operation, the two AES systems will combine to provide 37.5 MW of power for four hours on a nearly daily basis. Because the batteries count toward the utility’s local capacity requirements, that stored energy will replace fossil fuel generation otherwise deployed to meet peak demand in the evening.
“It's going to act like a sponge,” said Hanan Eisenman, SDG&E spokesperson. “Let's say the middle of the day you have overproduction of solar, you just soak that up with the battery and then you got the evening peak usage time at 5 p.m. ... we can release it at that time.”
http://www.utilitydive.com/news/ins...gest-lithium-ion-battery-storage-faci/431765/
So, these battery installations will collect and release the energy all in the high demand time. It's not being sold in the middle of the night when the price drops to peanuts. The idea is to carry over from the day into evening when the sunlight wanes to unusability, but everyone is still using a lot of electricity.