Why are fossil fuels not that efficient?

Answer 1

Because of the byproducts created by current methods of extracting the energy contained within fossil fuels (usually, burning them).

Burning fossil fuels releases carbon dioxide, the 'worst' byproduct, into the atmosphere, which in turn is thought to be a major cause of the increasing world temperature ("global warming"). Fossil fuels are the remains of life (for example, coal fields were once forests). Life as we know it is carbon-based, this is why carbon is released- usually in the form of carbon dioxide- when fossil fuels (or other forms of life) are burned. Carbon dioxide is a greenhouse gas- it's capacity to store heat is great. The increase in greenhouse gasses in our atmosphere is proposed as a reason for global warming.

Answer 2

Fosil fuels produce heat quite efficiently when burned with the right amount of air or oxygen. The inefficiency comes when that heat is used in a heat engine, which means a petrol or diesel engine, a steam turbine or a gas turbine. In a typical car engine, 25% of the heat energy is used to propel the car, while 75% is wasted via the radiator.

Answer 3

We use fossil fuels by burning them. The releases the chemical energy stored in them, and turns what's left into carbon dioxide and water vapor, which do not have useable chemical energy. trying to convert them back into some sort of fuel would take more energy than we would get out of it.

Answer 4

I've seen fuels used in basic carnot cycle engines average 30% efficiency of internal energy to work done.

Answer 5

Fossil fuels are polluting because they when burnt releases NOx pollutants and SOx pollutants which are harmful for environment.

Answer 6

- They are non-renewable

- Burning of fossil fuels leads to the greenhouse effect

- Fossil Fuels creates pollution