The Portland Press-Herald has a story about an interesting - if rather outlandish - alternative-energy proposal being floated for the Maine coast. (I’ve added it to my Google Map of alt-energy around the region)  From the story:

The plans presented by Riverbank Development Corp. in recent meetings here and on its Web site (www.riverbankpower.com) call for the construction of cavernous reservoirs and a three-story-tall power plant carved out of the bedrock 2,000 feet beneath the ground. At times of peak electricity demand, tidal water from the Back River would surge straight down four large chutes, through power-generating turbines and into the caverns, each of which would be 100 feet tall and 1,000 feet long. Then, when electricity demand is low and there is excess power going into the grid, the water would be pumped back to the surface.

The proposal calls for construction on the site of the old Maine Yankee nuke plant. It claims 1,000 megawatts of potential power (roughly the output of Seabrook), and the proponent says there are similar pump-storage systems around the world on the surface, but none underground.

The technology here seems pretty straightforward: It’s basically an upside-down tidal-power dam. Presumably there are good connections to the power grid, too, since this was a power plant already. The question is the finances, of course.

Tags: hydropower, Riverbank Development Corp.