I just got a new issue of Wired and have read an article on renewable energy. Turns out a lot of people (mostly rich people, so no worries here) lost money pursuing dreams of clean energy. None of the favorites of this race – Solar, Wind, Algae, Biofuels, Fuel cells – crossed the finish line first. The one that did was Natural Gas.
Natural gas is not renewable in conventional sense of the word. But it is much than oil and coal. And it turns out 24% of US electricity comes from natural gas. It’s also a most popular heating source.
A few interesting things about natural gas -
Shale gas
Recently US became a leader in production of shale gas. Experts say the drilling companies exaggerate the benefits and potential, but it looks pretty good – they say the whole country could be powered for 100 years on the shale gas alone.
Here are some projected basins (worldwide, but some countries are not included in the report) – 
Edit: as pointed out by William, the shale gas is very bad for water resources.
CNG-powered vehicles
Those are cool. Both my dad and my brother had converted their cars at the beginning of the 2000s to run on natural gas as well as on petroleum. And it was in Russia. There weren’t many filling stations but it was cheaper and cleaner. I always wondered why this thing never took off in the US.
There is more then hundred thousands buses here that run on natural gas though – 
Escaping gas
Technology is seldom perfectly efficient and we don’t get all the gas that’s out there and we can’t use it all for good cause. Some gas will escape.
There’s always gas where oil is. When the oil is the main target, a lot of natural gas gets wasted. There’s also blowouts (or gushers). One of the worst gushers happened in 1985 in Atyrau, Kazakh SSR, Soviet Union erupting about 60 bln cubic feet of natural gas. I pay one buck for a cubic feet to heat my home.
Summary
Although I believe in renewable and clean energy I propose we don’t loose focus on the old sources of energy and make them more efficient while making the energy consumption smarter. Let’s innovate both for tomorrow and for today.
Watch out about shale gas. The technology used to extract gas resources locked in shale is called hydrofracking. It is well known because it permanently contaminates the water table in many cases, literally by breaking the barriers betwen the aquifer and the natural gas reserves.