Answer to Question #98613 in Physics for Nahid

Question

Which fuel is the cheapest? With a practical investigation? Explain your answer

Answer 1

I believe that the cheapest fuel is trash. Take it, burn it and get energy. Such factories converting the trash into electricity are finely functioning in many countries, and the amount of trash produced on the earth each day is enormous and is growing from year to year. But such factories are expensive and require sophisticated technologies to protect the environment and work efficiently on different sorts of trash.

On the other hand, if we check prices per kilogram in the USA, we will see that 1 kilogram of gasoline costs about 10 times more than 1 kilogram of coal, and 1 kilogram of natural gas costs about 5 times more than coal. But that's not the case.

The fact is that we need to compare energy density (joules per 1 kilogram or 1 liter) of fuels per unit of currency.

Thus, atomic energy is supposed to be the cheapest fuel. Solar or wind energy can be even cheaper in regions where such technologies are well developed. And of course, everyone should keep in mind that "the cheapest" for producers or authorities does not always mean the cheapest for consumers. Moreover, different applications imply using different fuels and the cheapest in power engineering does not mean the cheapest in automotive engineering.

In most countries gasoline and diesel are the cheapest fuels for vehicles, that is why electric cars can't yet take their place. Power engineering based on natural gas and fuel oils or even coal is the cheapest in many countries.

The life of a human being is short and during such short life we may not feel the environmental problems regarding the consumption of non-renewable natural energy sources, but we should care about our future and future of the future generations, so let us burn trash and meanwhile develop solar and wind power systems.