What new renewable energy technology will have an impact on the U.S. marketplace in the next 1-3 years?

Wind power!

Depends upon how you see the impact. Already, the growth rates of renewable energy industries is significant - something like 40% more solar panels were produced in 2005 than 2004. A main hurdle (especially for solar energy in the US) is that it is still a very small part of the energy market, so the economy of scale benefits and supporting local industries haven't come into play - probably will be a while longer for solar. Wind is ahead in this respect. Both are very influenced by politics, how the incentives work out and the cost of electricity. For places like Japan and Germany with good gvmt support (and higher energy costs) photovoltaics has really taken off.

Wind power is the fastest growing renewable energy source in the world and in the US. There is a federal tax credit that all renewable energy in the US is dependent upon for viability. Given the new Democratic Congress, that tax credit will likely be extended for quite some time, creating a more stable and growing renewable energy market in the US.