Some promising news on the energy front. The Hydrogen Economy is very appealing in theory; hydrogen is the most plentiful element in the universe, is combustible, and when burned produces only water. One of the major hurdles is the fact that hydrogen does not exist in nature. Its simple structure (one proton, one electron), causes it to bind to other elements.
One of the major hurdles is that it takes a good bit of energy to seperate hydrogen from other elements for use. Harvesting hydrogen from water would be very green, but right now it takes electricity to do this, making it a net energy negative. That may be changing, scientists are working on a catalyst to sperate hydrogen from oxygen in water, similar to what plants do in photosynthesis. They are getting closer to making this work:
In other promising news:
New Solar Product Captures Up to 95 Percent of Light Energy
Energy Harvesters Transform Waste Into Electricity