Here’s another simple idea in the works for undersea energy storage of the intermittent power generated by renewables. See article and video at the New Scientist link below.
http://www.newscientist.com/blogs/onepercent/2012/04/green-machine-undersea-air-bag.html
This report is a year old already and I don’t know yet if it has proven to be a cost-effective storage option in practice. But the point of this posting, and the next one on 13 promising battery technologies, all of which are currently in development and working with a mix of venture capital and public funding, is to show how thousands of entrepreneurial people are at work with potential breakthroughs imminent.
aviott 