Many readers have expressed interest in learning more about the water consumption of concentrating solar power and how measures to reduce it might impact system efficiency and cost. After my recent CSP post, “World’s largest solar power plants with thermal storage to be built in Arizona,” Michael Hogan wrote in the comments (here) about a low-water-consuming cooling system he had experience with. I asked Hogan, a long-time power industry executive and currently the Power Programme Director for the European Climate Foundation (bio here), to write a longer piece for Climate Progress. Here is what he put together, with links and figures (click to enlarge).
EXECUTIVE SUMMARY: If concentrating solar power (“CSP”) is a core climate solution, indirect dry cooling systems (also known as “Heller” systems) will be a crucial enabling technology, since large-scale CSP will be located in desert regions. US power companies have long favored direct dry cooling systems for fossil plants, probably because of the visual impact of Heller systems. But Heller systems have long experience in certain regions and will probably play an important role in the success of large-scale CSP. This is due to their higher efficiency, smaller footprints, quieter operation, lower maintenance, higher availability, and more flexible site layout. Heller systems can reduce water consumption in a CSP plant by 97% with minimal performance impact. The height of the cooling towers should be less of an issue in remote desert locations, especially since the central tower in power tower facilities will be of comparable height.