Enter frequency responsive heat pumps, much cheaper & easier to store energy as useful heat (especially if it can offset peak demand)

http://www.nytimes.com/2007/11/07/business/businessspecial3/07cutoff.html

Alternatively, a utility can pay demand-response companies to reduce use. For instance, a utility might pay Comverge $70,000 to $80,000 a year for each megawatt that the company can commit to eliminating from the load. By contrast, if a utility builds a power plant, it could pay $400,000 to $2 million for each new megawatt of capacity, depending on the type of power plant.

There are such low return rates on cash savings, and huge potential for capital intensive demand management and renewable / nuclear energy schemes which fit the pension investment model, it could all work very well.