I worked on this CSP project back in 2009 when it was still on paper. It's really exciting to see forecasts/estimates/hypothesis that do work out i.e. store heat energy to serve peak hours when the sun isn't shinning. More importantly, and what I really look forward to, is that this carbon-free technology is to a large extent "validated" meaning that this kind of projects are now less risky, more viable and financeable. Hopefully this will push down the price of CSP + storage, which will make it more attractive to both utility incumbents and new entrants/energy startups.
I've been puzzled for some time: Is anyone / why isn't anyone working on more flexible and responsive coal and nuclear plants? Instead of storing renewable energy, it would be more efficient, less complex, and less capital-intensive (one would think) to consume the renewable energy immediately and make up the difference between supply and demand with flexible traditionally-fueled plants.<p>I'm sure there's a good reason. I just don't know what it is.
I find it interesting that we're still using water to transfer the energy. Has there been much research into finding better ways to create electricity than stream => turbine? Is there anything interesting happening in this area?<p>It just seems to me that the process of turning water to steam to impart kinetic energy to a turbine is incredibly wasteful, and all we seem to be researching are fancier turbines. I would love to be shown otherwise.
Is this a big deal? Molten salt plants have achieved almost a day with no sun. Example: <a href="http://www.torresolenergy.com/TORRESOL/gemasolar-plant/en" rel="nofollow">http://www.torresolenergy.com/TORRESOL/gemasolar-plant/en</a>
This is a big deal, one of the key benefits of Coal/Gas/Oil power stations is their ability to provide frequency response (where the power output is adjusted to keep the AC as close to 50 Hz as possible) or to participate in a balancing mechanism (where generators place bids on providing minute by minute changes to their power output). Until now the only thing a solar/wind/nuclear generator could do was turn their generators on or off. That severally limits the proportion of renewables you can reasonably have on your grid[1]. But this technology looks like it'll give a renewable generator a way of dynamically adjusting their output to match demand.<p>[1] You do get controlled generation with biomass, but the efficiency is terrible and you need that land to grow food, so it'll (hopefully) only ever be a niche technology.
3 square miles is 7.77 square km. Just over 1 kW of sunlight falls per square meter, so I will round up and say that there are 8 GW falling on the plant total.<p><i>So 280 MW of production is 3.5% efficient of peak irradiance.</i><p>BUT average irradiance is smaller than peak:<p><a href="http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook/atlas/" rel="nofollow">http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook...</a><p>It looks like 5 kWh/m2 for Arizona, so that's 38.85 GW per day irradiance on 7.77 sq km. Assuming the plant can put out its maximum capacity for the 18 hours it runs each day, that's 280 times 18 = 5 GW per day.<p><i>So it's operating at almost 13% efficiency of average irradiance.</i><p>That is very good, considering that they are able to store heat much more cheaply and environmentally friendly than storing electricity in batteries.<p>The most important thing of all is that it doesn't have to wait for innovations in photovoltaics. Anyone can buy land, set up parabolic mirrors, and tinker with forgotten heat engines like Stirling cycle engines or Tesla turbine engines that easily achieve 30, 40, 50% efficiency and approach the Carnot limit. Conversion of motion to electricity is a solved problem at 95% efficiency.<p>Oh and these plants can be supplemented by biomass, say biodiesel from algae or fuel pellets made of hemp. If that's too granola for the fossil fuel industry, they can also use natural gas.<p>In fact if you study this long enough, you find that there are only two real hurdles: energy storage and connection to the grid (made difficult because of resistance from established utilities). Generation turns out to be relatively inexpensive because there's a sea of free energy all around us. To put it in perspective, Grand Coulee dam puts out less power than the irradiance falling on the solar plant. It's just more efficient at converting the motion of falling water to electricity:<p><a href="http://en.wikipedia.org/wiki/List_of_largest_hydroelectric_power_stations" rel="nofollow">http://en.wikipedia.org/wiki/List_of_largest_hydroelectric_p...</a><p>It puts out 6.8 times 24 = 163 GW/day. That's 33 of these solar plants. So every 100 sq miles (260 sq km) of desert is equal to the 324 sq km of area flooded by Grand Coulee.<p>Solar thermal is the hydroelectric of the future and uses less land, which will only improve going forward. IMHO this will someday dwarf wind and nearly eliminate intermittency issues.
I assume this is a molten salt plant? If so, I didn't think that was a new thing because I've heard about it plenty before now. Is this the largest solar-thermal plant doing this? The first?