The bigger problem is the environmentalists that want to stop ANY form of energy production including solar farms in the Sonora desert, wind farms off of the coast of New England among others.
References :

Remember they say if we don’t cut way back on fossil fuels within 10 years global warming is irreversible. My conclusion, we are totally screwed. So debating it is kind of pointless. It is here, what can you do. I don’t see the EU or any of the nations really getting anywhere with it. Plus with no real alternative energy sources that can be done anytime soon, it’s over.

People who are worried about global warming say they have the answers to it, but then every year passes and nothing happens. I don’t think they have an answer. It’s either to expensive, or the public doesn’t go for it because of all the draw backs.
References :

“An analysis of the current energy alternatives is not reassuring. Solar and wind are renewable, but we now get less than one percent of our national energy budget from them; rapid growth will be necessary if they are to replace even a significant fraction of the energy shortfall from post-peak oil. Nuclear power is dogged by the unsolved problem of radioactive waste disposal. Hydrogen is not an energy source at all, but an energy carrier: it takes more energy to produce a given quantity of hydrogen than the hydrogen itself will yield. Moreover, nearly all commercially produced hydrogen now comes from natural gas–whose production will peak only a few years after oil begins its historic decline.”

http://www.oilcrash.com/articles/party.htm

Given the lack of funding for research into renewable energy, the absence of urgency and political will to convert to cleaner sources of fuel, the overwhelming cost of a complete conversion, the huge technological and logistical problems associated with the deployment of new energy systems, and the fossil fuel industry’s stranglehold on energy policy, it will be a very long time before fossil fuel goes away — well over 50 years.

Oil depletion will probably have a bigger effect on the effort than concern over greenhouse gas emissions; that is, when the cheap oil is gone, we’ll be forced to turn to other sources of fuel. But it also takes a lot of energy to develop new technology and replace the old, and we’ll be doing this at a time when energy will already be scarce — something Heinberg talks about in his book.
References :

Fortunately, battery tech is improving. Check out the Tesla Raodster or Nissan Leaf. Performance of electric cars seems like it’s be pretty good (Check out the Leaf or Volt specs for example, looks like it has space etc!), the biggest problem is battery capacity. It is currently increasing at about 8%/yr according to Tesla and lab batteries have demonstrated 5-10 times current capacity using silicon nanowire or air electrodes.

If we have batteries with ~5 times current energy density, then electric cars should work. This is foreseeable - possibly within a decade for the first ones.
References :

The technologies on the table right now include electric, hydrogen, and biofuels. My personal prediction is that the future will be powered by algae-based biofuel, but it could be electric, hydrogen, or something we have not even thought of yet. I’d imagine it will take at least 30 years for the majority of the world’s transportation to run on something other than oil or natural gas.
References :

But if you’re looking for "green" energy, the answer is "when we have one that works better than what we have already." It will probably happen, someday. In the mean time, Coal, oil and nuclear work really nicely.
References :