There is no question about the environmental advantages of renewable energy sources such as sunlight, wind and moving water but the problem about these energy sources is their inconsistency and reliability during bad weather or drought-riddled times.

This being said, renewable energies are not 100% clean. There are pros and cons. It is good to keep that in mind. For instance, dams could have dramatic consequences on the ecosystem.

It is funny to quote Hawking on the topic of nuclear fusion. Hawking is famous, for sure, and his work is amazing. However, the domain of the energy is not at all his field. Therefore, why quoting him instead of a real expert?

In addition, saying that fusion is good is meaningless... This is promising except that this is not for tomorrow. We are not even sure that we will be able to rely on fusion in 50 years from now...