The company says it envisages the two schemes would have a combined storage capacity of 600-1,200 megawatts (MW). Both plants would require the construction of a dam with a large upper reservoir, though pumping and electricity generation would be carried out underground.
SSE says it is currently consulting with the Scottish government on the scope of the environmental impact statement it would need to include in its official development application, which it expects to submit by 2011.
The
