After Gutenberg

The U.S. Department of Energy Solar Energy Technologies Program has set cost targets for utility-scale electricity generation using concentrating solar power technologies. They are nominal levelized cost-of-energy targets of 7–10¢ / kWh by 2015 and 5–7¢ / kWh by 2020.

FOA (Funding Opportunity Announcement) notes in the U.S. Southwest that CSP (Concentrating Solar Power) has been established as one of the most attractive renewable energy options.

To encourage further development, the DoE is addressing certain market barriers, i.e., the funding opportunity focuses on three main RD&D areas:

1. Thermal energy storage


A molten salt system can be can be a means to store thermal energy, thus mitigating the problem of an intermittent source for generating electricity at night or during cloudy weather.

2. Parabolic trough component manufacturing


According to Jim Fraser, the Luz parabolic collector is designed for mass production and cost reduction by economies of scale. Solel is installing an upgraded version of this collector for a solar thermal project in Spain.

3. Advanced concentrating solar power systems and / or components.


Utilities are willing to invest in ISCC (Integrated Solar Combined Cycle), whereby recovery of heat from a gas turbine is combined with solar thermal energy and used to power a steam turbine, because combined cycles show the highest system efficiencies. Still, the use of two turbines with ISCC adds significant cost, which is one reason for research into other lower cost generation.

A thermally integrated system is just one example of advances in concentrating solar power. Another example previously used in this blog was the combination of photo voltaic and thermal technologies within one concentrating system.

Also previously noted by Jim Fraser back in February 2006 was the use of a stirling engine rather than a steam turbine. Without any incentives Stirling Energy Systems demonstrated the cost effectiveness of a Stirling installation for Southern California Edison.

Lastly, solar power systems improve efficiency with tracking, but these components add complexity and cost, plus they represent an energy demand as does the pumping of a fluid through a heat exchange system. Thus, research also is focused on how to reduce the cost / improve the efficiency of the dynamic components of solar thermal technology.

And, as with other energy initiatives, these DoE cooperative RD&D awards are intended to encourage collaboration between industry and universities. A leading university center in the desert field of concentrating solar power is the National Solar Energy Center at Ben Gurion University in Israel.