Conventional sources of energy such as coal, natural gas, petroleum, wood, etc. are all carbon-based fuels and mostly are fossil fuels. Their significance to our development cannot be underestimated, however they do have certain disadvantages:
- Climate change: The biggest drawback of using fossil and/or conventional fuels is the amount of carbon dioxide they release upon combustion. As we know, carbon dioxide is a greenhouse gas and is a prominent contributor to global warming and climate change.
- Limited quantity: Fossil fuels are formed over millions of years and have a limited quantity. However, our rate of fuel consumption has been rising over the last century and has become unsustainable. In other words, at our current level of conventional fuel consumption, we may run out of them in the next few decades (depending on the fuel in question).
- Cleaner fuel: Fossil fuels generate gases and some produce a lot of solid residue (fly ash from coal, etc.) as well. All these combustion products need to be disposed of as well, adding to the cost of fuel consumption.
- Unequal distribution: Fossil fuels are unequally distributed among various geographical regions and this leaves the possibility of some countries holding the world at ransom (similar to oil crisis of 70's).
Alternate fuels are cleaner, widely distributed and do not generate carbon dioxide (during usage) and hence are more environmentally-friendly.