Charcoal is the cheapest source of heat. It is also good for foods that take longer to cook. Charcoal does not require any maintenance and it lasts longer. Kerosene stove is another cheap source of heat. Although kerosene might be expensive sometimes depending on changes in the economy, maintaining a kerosene stove is quiet easy. Which is the cheapest source of heat at your place?
Charcoal and kerosene really are among the cheapest source for fuel and heat compared to the LPG gas and electric stove but depends mainly on which you are located. There are countries that have really low electric cost and so using charcoal or kerosene is not much of a thing. Chopped woods and also coconut husk/shell is a cheap source for heating.
As much as charcoal is a cheap source of heat, the rate of deforestation for this purpose is alarming and of great concern. Cutting down all those trees and releasing carbon dioxide into the atmosphere isn't ideal. We should try to be cheap at the expense of our sustainability. I think kerosene should be the next cheap thing. It is a by product of crude oil and I believe is if sold at a subsidized rate, it would be affordable to almost all.
