Continued from Part One.
Not all renewables are quite as dubious as those outlined in Part One, though; at least in terms of being able to pin down the economics.
Two US solar power producers will shortly be able to make an accurate business plan for their solar power projects, not least of which because they will not have to budget for power supply during non-daylight hours.
BrightSource and SolarReserve are building solar array projects in California and Nevada, respectively. A NY Times article explains that both companies will use thousands of computer-operated, poster-size mirrors aiming sunlight at a tower that absorbs it as heat.
SolarReserve absorbs the heat in molten salt, which can be used immediately to boil water, generating steam that turns a conventional turbine and generator. Hot salt can also be used to retain the heat for many hours for later use. BrightSource heats water that can be used immediately as steam or to heat salt for storage.
Is It Cost-Effective?
Neither plant will currently operate without subsidy, but the technology is still young and given time, may well develop to be economically viable.
Both firms are seeking to capitalize on differential electricity pricing that they believe will evolve to meet demand at peak times. The fundamental benefit of such projects over wind is that days of sunlight, at least in states like Nevada and California, is much more reliable and predictable than wind power, and the ability to store the power for use when the sun doesn’t shine avoids the need for expensive backup generating capacity.
It may not be as cheap as gas-fired power generating capacity, but at least it is a genuine replacement for a conventional plant.