The group of conventional energy sources is one of the three main type of energy sources.

We are using the conventional / nonrenewable energy sources every day in different form: coal, natural gas, petrolium, electricity.... The conventional sources are not able to recreate in a short period of time.Energy sources help us, through the different ways, to get energy generate power.

Most of the energy energy we used is from nonrenewable energy sources: oil, natural gas, and coal.  We know them as fossil fuels because they were formed over millions and millions of years by the action of heat from the Earth's core and pressure from rock and soil on the remains (or "fossils") of dead plants and animals. 

Another nonrenewable energy source is the element uranium, whose atoms we split (through a process called nuclear fission) to create heat and ultimately electricity. 

Nitrogen is a chemical element and it is a common element in the universe and also is used as energy source. We use all these energy sources to generate the electricity we need for our homes, businesses, schools, and factories.

http://www.energykids.eu/conventional-energy-sources

I would suggest to read some articles related to home energy management from IEEE Transactions on Smart Grid, IEEE Transactions on Power Systems.

Conventional sources of energy include the fossil fuels "petroleum fractions, natural gas which is largely methane, and coal". The use of them could be optimized if they can be utilized in multipurpose such is using a kerosene stove to warm the house , to bake bread, and to heat or boil water. However, there needs to be a guiding process for the public through the media to how to utilize an equipment for 2 or 3 advantages.

My opinion is use some Non conventional source of energy at home. this will help in energy crisis and pollution free. like...

Solar water heater.

Electrical solar panel.