It is perhaps too early to talk of an energy "crisis".

Fossil fuels have been the cheapest and most convenient so far

But take your pick from terms like "serious concern" and "major issue" and you will not be far from the positions which analysts are increasingly adopting.

The reason for their concern can be found in a set of factors which are pulling in glaringly different directions:

Demand for energy, in all its forms, is rising

Supplies of key fuels - notably oil and gas - show signs of decline

Mainstream climate science suggests that reducing greenhouse gas emissions within two decades would be a prudent thing to do

Meanwhile the Earth's population continues to rise, with the majority of its six billion people hankering after a richer lifestyle - ...
Source (BBC NEWS)

BBC NEWS | Science/Nature | Energy gap: Crisis for humanity?