Read the papers (especially the Economist), it is on the way (Where will you buy your hydrogen...)

Remenber: Hydrogen is not a source of energy, it is a way of storing it... To produce hydrogen (with electrolysis) you need energy, and this energy can be a clean energy (e.g. thermal energy like they use in Iceland).

Michiel's comment is spot on. This point is often lost.

You can convert Natural Gas to the elements required for a fuel cell. The Fuel Cell process created heat, so you might be able to use that to help you heat your home as well.

I do not think this technology is ready for market yet, but I have heard that a fuel cell that runs on natural gas (which it internal converts to hydrogen before use) can convert as much as 70% of the natural gas energy to electricity. For places like California, where over 40% of electricity comes from natural gas, a direct comparison is very relevant. When a natural gas power plant is used to make electricity, generation and transmission losses cause only about 30% of the natural gas energy to reach the end user. Therefore, even a natural gas fuel cell would be a great improvement over taking electricity off the grid. As far as I know, most of these plants do not even use cogeneration.