Posted on 01/03/2008 6:04:24 AM PST by Uncledave
They mean dry salt that has been melted.
And taters can power clocks.
I'd hate to be caught underneath that shower
I can't see any other feasible way to store energy to generate solar power 24/7. Chemical energy storage would be wasteful, espensive and dangerous. How many batteries does it take to store 8 gigawatt hours (500 MW for 16 hours)? Quick calculation, that's 25,000 tons of high-capacity lithium-ion batteries. I'd love to see the capacitor bank that can hold that, hate to see it explode.
I also can't see how potential energy would work well, as you'd need a lot of mass and height difference. Kinetic energy, that would be the biggest flywheel farm ever made. Thermal seems the best, and we already have a lot of experience in pumping very hot stuff around in nuclear reactors.
Because a lot more energy can be stored or released when a meterial undergoes a "phase change" (melts or boils), than just that due to the materials "heat capacity". And the phase change happens at a constant temperature (water turning to ice---or steam).
It's really very old technology, but it's probably the first commercial use in a power generating application.
Dry salt that has been melted.
The thermal radiation will dissipate regardless of the insulation used for the storage tank.
Doesn’t anybody remember basic thermodynamics? There will always be a net loss of energy due to entropy that increases with the number of transforming phases. By the time the solar furnace melts the salt, the salt is “stored”, the heat from the salt is transfered into steam which then drives a turbine that generates electricity only a fraction of the energy originally made from sunlight will be available. These “Rube Goldberg” solutions are not the answer to our energy crisis anymore than corn based ethanol.
That would suck. I wonder how much salt it takes to store that kind of heat. The Solar Two tanks weren't that big but it was also only 10 MW. This will probably use tanks the size of our current fuel storage tanks. For reference:
That brings up another problem -- where do you put the tanks when they're that big? Underground?
Of course that's true. But remember the solar "fuel" is free. It all comes down to cost/watt. I doubt it's as low as coal or nuke, and certainly there's some tax subsidy with this (not that coal and nukes don't have their large slice of pork).
Another point is that electricity prices are highest in peak hours - so at the sunniest/hottest times when prices are highest the project would be running at its best pace.
so at the sunniest/hottest times when prices are highest the project would be running at its best pace.
I'd think photovoltaic, which is going down to $1/watt for the cells, would be much better for helping the grid with peak demands.
Interesting that the new GE hybrid locomotives also use molten salt in a giant battery. They say it can store and deliver jillions of amps, unlike most batteries.
bttt
Where have you read they use molten salt?
Thanks!
I'll drink to that!! But I will wait till this evening.
More like not many understand it to start with. That's why you see the shrill corn ethanol fanatics trying to shout down those who do on forums like this one. Heat loss via radiation occurs based on the 4th power of the absolute temperature, so salt at 1000C is going to be losing heat via radiation 625 times greated than the same amterial at 200C. What could they insulate it with to keep the heat in for a long time?
sorry the C should have been a K
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