"Non-Conventional" sources of energy include which of the following options?

1. Solar energy
2. Electricity
3. Firewood
4. Tidal power
5. Dried dung

A and D only

Commercial and non-commercial sources of energy collectively are known as conventional sources of energy. Whereas, there are three other sources of energy which is commonly termed as non-conventional sources — solar energy, wind energy and tidal power. Being a tropical country, India has almost unlimited potential for producing all three types of energy if some appropriate cost-effective technologies are used.