There is a lot of green technology that makes the news but is far from being able to be practically used. ‘Clean coal’ and hydrogen fuel cells are two that spring to mind.
Something I hope will work is biological power sources such as biogas from algae. I suspect bio power has the potential to be a cheap and robust energy source if it can be correctly developed.
This person (who certianly seems to know what he is talking about) reckons its not viable: ‘the prospects are dim’.
Lets wait and see.