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Molten Salt-Based Solar Power Plant
rcastro0 writes "Hamilton Sundstrand, a division of United Technologies, announced today that it will start to commercialize a new type of solar power plant. A new company called SolarReserve will be created to provide heat-resistant pumps and other equipment, as well as the expertise in handling and storing salt that has been heated to more than 1,050 degrees Fahrenheit. According to venture capitalist Vinod Khosla 'Three percent of the land area of Morocco could support all of the electricity for Western Europe.' Molten Salt storage is already used in Nevada's Solar One power plant. Is this the post-hydrocarbon world finally knocking?"
While I would love to believe some form of solar power would meet the world's needs, it simply isn't feasible with current technology.
We'll probably have wormholes, sexbots and universal prosperity before solar can meet the demand.
"The fight for freedom has only just begun." - Geert Wilders
" Is this be the post-hydrocarbon world finally knocking?".....
It was here 50 years ago with nuclear power. Thankfully, it's finally getting attention again.
Except that you can't easily get electricity from Morocco to Europe. Transmission of electricity isn't lossless or free.
1. Nuclear power is not carbon neutral. Uranium is mined, and nobody is running mining equipment on biodiesel, nor are they transporting it to power plants using biodiesel, ethanol, or even renewable generated electricity on electric locomotives. To be sure, the amount of carbon is extremely low per kWh of electricity generated, but very small > 0, even for very small cases of very small.
2. As you know, nuclear proponents continually ignore the major immediate problem with nuclear power -- waste storage. Nobody wants more glass-encased nuclear waste in their neighborhood, and presently nobody wants some other neighborhood's nuclear waste being transported through their neighborhood. The nuclear industry has got to find technical and political solutions to these problems before society will embrace nuclear as a green solution. I'm not arguing that burning coal or oil is safer or cleaner than nuclear, just that any change to a status quo requires more than a slight or obscured imbalance, which is how the public currently perceives the status quo.
3. What is Hubbart's Peak for uranium? I have no idea, but it surely must have one.
4. Which nations have substantial amounts of useful uranium? What would the balance of power be if those nations became the new Saudi Arabia of energy?
5. Solar off-peak is simply not a problem, not for a long time. Peak demand is highly correlated with sunshine in most of the world -- solar could serve quite effectively as the peaking plant, relying on other types of generation for base load. Electric storage is just not a major issue for solar -- it might become one for wind but it wouldn't be that hard to operate other green energy plants in a negative correlation to wind, ie burn woodchips when the wind isn't blowing, but not when the wind is blowing.
6. That said, plug in cars might change that formulation substantially, since most people would plug in their cars at night thereby adding demand off-peak [and off-sun]. If/when that happens, much of (5) becomes moot and there'd be some shifting of nighttime use [industrial, it's cheaper] to daytime and there'd be encouragement for folks to charge during the day [plug in jacks at car parks] to help keep demand during the day higher, when production due to solar is higher.
7. Ultimately, this doesn't matter. Solar production in the US is well less than 1%. Even at 10% there won't be a necessary substantial change in infrastructures or demand shaping. So, until then, more of every kind of renewable electricity generation is better, and none of it will create challenges. And, of course, nuclear may or may not be greenish, but it is not renewable.
Support a few technologists in Washington.
What are you smoking?
It requires an absolutely tiny amount of uranium to run a nuclear plant, compared to the 10,000 tons/day that a 1GW coal plant uses. Uranium is rare, but you don't actually need that much *of* it. 95% of the fuel used in fission plants can be reprocessed. Coal producers are chopping off the tops of entire *mountains* in Appalachia;
"Disposal" isn't as big a problem as it's made out to be; reprocessing reduces the amount of waste produced tremendously, and storing a little waste for a time is a whole lot better than *not* storing it and dumping it into the atmosphere, as we're doing with coal.
There are other forms of power generation than nuclear, but at the moment it is the only proven, scalable, clean, and economical alternative to fossil fuels for power generation. Perhaps solar-thermal (as in this article) or geothermal or tidal power or some sort of wind power can be used to carry a lot of the load, but nuclear power is available now, and the only thing lacking is the political will to implement it.
France had that political will, and now they have the cheapest power and the cleanest air in Europe.
when the sun is out, and Wind is great when the Wind is blowing, but they are not viable for providing base load power needs.
Nuclear is ideal for providing base-load power (30-40% of peak capacity), suplemented by Solar, Wind and Tidal power.
This kind of thing has been suggested for use in high-power spacecraft, and it's not necessarily sodium salt that's the storage mechanism.
I don't see why you'd lose much efficiency. You'd chose a salt that was molten over the operating range, and no matter what, you cannot exceed the temperature limitations of the other materials you've built the thing from, so that's your design temp. Because of the T(t) smoothing effects, you'd be able to run the generator at maximum efficiency for most of the time. Thus, you can size your machinery to the average capacity rather than the peak available solar input. Not spooling the generator up and down as the sun waxes and wanes is great for efficiency.
For instance, you might pick a salt that has a liquid-solid transition just below your desired T_hot, ensuring even temperature until all the salt solidifies. This has the added benefit that, depending on the expansion characteristics of the salt in question, you have a number of ways to evaluate the remaining generating capacity.
With good insulation, and a fixed installation can be made arbitrarily well insulated, you would lose a lot less energy than storage in batteries, and it scales very well: the larger the installation, the thinner the needed insulation is relative to the total volume.
The main loss would be radiation from the absorption patch. Presumably you'd mitigate this by having some kind of louver or hatch that you could close to insulate that during the night and overcast days. You could also take advantage of the much lower-than-the-sun temperatures, and use a covering that is transparent to visible light, but reflective to lower frequency light. Although there would still be a fair bit of radiation in the visible at reasonably efficient temperatures.
Can you be Even More Awesome?!
It is not just that they are chopping whole mountains off it is that there are 1000's Coal Fires in mines underground that are adding anything from 1-5% of the worlds Co2.
An Education is the Font of All Liberty
I guess the relevant terms should be exhaustable vs. non-exhaustable. Using sunlight for power doesn't change when the sun will die. Using fossil fuels for power changes when the fossil fuels will run out.
What sound do people on rollercoasters make? Hint: it's not Xbox 360.
This is going to take years and it's a matter of people seeing a lot of solar hot water collecters on rooftops before governments decide it is a safe bet to go for large solar power projects - I think industry on it's own will hit exactly the same problem the nuclear power advocates have. For really big thermal plants they want government money because they can't get commerical finance. Electricity is heavily regulated in most places anyway so it usually takes government involvment to just get a foot in the door. This sometimes involves convincing relatively old people who did not have the benefit of finishing high school of the merits of a project - hence the delay until solar thermal (eg. hot water) comes into the personal experience of the people regulating things.