From Van Snyder, La Crescenta, California, US
Glenda Dixon asked: “Why not use thermodynamic systems to get heat from the [warming] seas to generate electricity and heat local homes?” One reason is that the devices needed would be huge because their efficiency is low (Letters, 26 August).
The only example that ever worked for any length of time was built by Japan for the island nation of Nauru. It produced 120 kilowatts (not megawatts). Of that, 90 kW were used to run the device. It relied on a mixture of water and ammonia, which poses a significant environmental risk if it leaks out.
