Concentrating solar plants are a source of renewable, utility-scale heat and electricity. There are several competing CSP designs, but the most prominent are parabolic trough and solar tower. Parabolic trough is the most deployed, and thus easiest to finance, however, it has technical limitations which restrict its ability to be cost-competitive with fossil fuel generation. Solar tower designs, on the other hand, have much greater potential to compete with fossil fuels.
Concentrated Solar Thermal Plant (Tower) in the California Mojave Desert, United States
In the solar tower design, mirrors, called heliostats, track the sun on two axes, and concentrate solar radiation onto a tower. The receiver at the top of this tower contains a heat transfer medium - such as oils or salts - that captures the heat. The heat is then converted into electricity using a steam cycle turbine. Importantly, it can also be stored in low cost thermal energy storage units (TES), which are cheaper and easier to build at scale than electrochemical batteries - and all other competing technologies. This cheap and easy energy storage makes renewable heat and electricity available when the sun is not shining.
Even today, this unique attribute makes CSP electricity generation highly valuable in the green energy mix, suitable for baseload, peaking, and load balancing services.
According to our technical analysis, the power tower design has the potential to reduce the levelized cost of dispatchable energy (LCODE) down to 50 $/MWh (0.05 $/kWh) which makes it the ideal candidate to achieve the goals of SunShot initiatives baseload target. We believe tower CSP is the most promising renewable system to replace baseload power systems like coal, gas and nuclear power plants in the foreseeable future.