Create some local storage for peak shifting. Cheaper to heat one big insulated building. Even use passive solar for much of the heat.

Another battery solution is likely to be “degraded” EV batteries. Once their storage capability drops to 80% or so people are going to swap them out in order to maintain driving range. Since size and weight aren’t that important for static storage we could see these batteries having a second life for utility storage. Utility companies buy the somewhat degraded batteries, rack them up in neighborhood storage buildings and the EV owner gets help buying their new EV battery.

Here are some sites you might want to check.

The first belongs to Craig Severance who does some very good “numbers” piece. His cost analysis of nuclear is first rate.

http://energyeconomyonline.com/Utility_Scale_Storage.html

Here’s another which compares cost of different storage methods. Although flywheel cost may have dropped since these numbers were put together.

http://arstechnica.com/tech-policy/news/2009/01/storing-power-on-the-future-electric-grid.ars

Finally, here a new sodium ion battery being developed at MIT. If it works out it should provide some quite inexpensive storage possibilities.

http://www.technologyreview.com/energy/24043/?a=f