CanalWays

Solar Panels:
It currently takes more energy to produce a solar panel than it can create in it's lifetime. They are great for energy in remote areas where there are no power cables, but until we have a different technology they are not as green as they look. (Yes, there are people working on this).

Hydrogen and cars:
You can currently run an internal combustion engine directly from hydrogen. You will get a similar efficiency to a fuel-cell and electronically controlled motor drive.

The IC version is currently a lot cheaper. There is a downside that you still need oil and still have some hydrocarbon emissions from the burnt oil, but the emissions are mainly water. Probably the way to go for a while.

Windfarms:
Have you ever wondered what happens to the climate when you take several GW of energy out of the wind currents across an area? Somebody suggested a link between the killer heatwave in France a few years ago and the number of windfarms in Europe.

Solution:
After the global melt-down, we all go back to living in tents tending to sheep :)