I had a great time at the ESA conference in Charlotte. The energy storage industry looks, to me, like renewable energy did in 2002. I think people are starting to understand that in order to meet the RPS targets that many states have demanded will require massive deployment of storage resources.
However, in other ways, it's not clear that this is like 2002 at all. It's more like solar in 2004 or fuel cells in 1996. There is so much interest in different technologies and everyone is trying something new. Just like solar has concentrating thermal-2-axis fresnel, dish (2-axis parabolic), 1-axis fresnel, 1-axis parabolic, monocrystalline silicon, polycrystalline silicon, front contact, back contact, triple junction, CIGS, thin film, concentrating PV, and many others, and just like fuel cells had companies developing PEM, phosphoric acid, solid oxide, direct methanol, molten carbonate and alkaline cells (and others if you start getting into metal air batteries), storage is seeing the same explosion of choice.
The established players are the battery companies. NJK, in Japan, has been selling Sodium Sulpher (NaS) for years to firm renewable capacity (due to policy decisions). Recently IPO'd A123 is moving from its transportation focus to sell utility scale battery solutions. Several other battery companies were also there.
The newcomers included flow batteries and flywheels. Beacon Power, of course had a strong presence, but it was neat to see other developments in flywheels by other early stage companies present.
With the ARRA funding now deployed and the ARPA-e storage grants getting underway, it will be very exciting to see what happens in the next 12 months. Given how things have been over the last 18 months, finding a sector that looks like 2004 is welcome indeed.