Advantages:

1. Non-conventional sources of energy are usually inexhaustible. They do not pollute the environment.
2. Nuclear power is emitted in large amounts.
3. Most non-conventional sources of energy cost less.
4. These forms of energy are safe to use and clean.

Disadvantages:

1. Windmills are costly to set up. So using them to harness wind energy is costly, even though the electricity generated from it is cheap.
2. Setting up windmills disturbs radio and TV broadcasts.
3. Harnessing tidal energy destroys the natural habitats of wildlife.
4. Moreover, tidal energy is difficult to harness.
5. Obtaining nuclear energy from radioactive material generates radioactive waste. It is expensive too.
6. Biogas, although useful and renewable, contributes to the greenhouse effect.