Vault’s Viewpoint on Solar Energy. Evaluating the pros and cons of solar energy can help people who are considering investing in solar panels determine whether the investment is worth it.

Hydropower dams can help on that front. The fewer we tear down, the easier it will be to stop burning coal, oil and gas. At the same time, though, I know my perspective is limited.

Hydropower pros and cons. Hydropower has several advantages. Once a dam has been built and the equipment installed, the energy source—flowing water—is free.