A. Coal

B. geothermal

C. Natural gas

D. Petroleum

Peak oil is not running out, it's simply where our ability to improve production no longer meets the growth in demand. Nature has been collecting solar energy through photosynthesis and storing it chemically in fossil reserves for millions if not billions of years. Although the process is far from efficient, the fossil reserves are truly immense though much are beyond our ability to claim. We will not run out but we will have problems meeting our needs and with their use upsetting the cycles of our environment and climate.

I would suggest petroleum. Coal is now not used on a large scale and geothermal energy is continues from the environment. Natural gas is still largely available where as petroleum is used on a vast scale with agriculture,fuel and in chemicals also being a non-renewable source of energy and with a growing population demand is rising at a very fast rate.

Petroleum, Natural gas and Coal as they are limited in quantity and time is the only factor.

There is more coal,oil, coal seam gas, natural gas,in the ground that we ever dreamed of,we are just touching the surface.....the earth will end by other means....asteroid hit...etc, before we run out of recources to provide power ect.

petrol then coal

geothermal is already rare

our ignorant world should start using Nuclear Energy for god's sake...

The energy is there and we have the technology to tap the supplies. Even with prices as high as they are, gasoline refined from crude oil is still the cheapest form of energy for our automobiles. But that may be about to change.

D. Petrolium.

A. Coal

B. geothermal

C. Natural gas

D. Petroleum