It's a self-fixing problem, DUmmies. If they are actually 'Fossil fuels,' they will all be used at some point...no matter how slowly, they will ALL be used, ultimately, so what you are really upset about is just the rate of usage, not the usage itself (If only you were smart enough to understand the difference, but that's a forlorn hope...). The net effect is therefore THE SAME with or without your stupid, wasteful dithering with false alternatives.
Economically, it makes a Hell of a lot more sense to use the fossil fuels until there is an alternative available that can be had at a comparable price per unit of energy delivered (Counting in all the subsidies, tax discounts, production costs etc. into the comparison for both). Until that happens, moving away from fossil fuels is like entering our economy in a swimming race with India's and China's but making it wear anchor chains and swallow a bunch of downers first. Yeah, there's nothing wrong with funding the science to explore alternative tech, it just doesn't make a lick of sense to force implementation until fossil fuel costs rise to comparability due to decreasing supply.
And on the overpopulation thing - you first, bitches.