Solar and wind get a lot of press and have a lot of great attributes. In many cases, they are the right solution for particular energy needs in particular places, but they’re far from everything… Here are some of the major sources of renewable energy and the top pros and cons for each.
Good: Sunlight is free and there’s a lot of it. Solar cells last a long time and are increasing in efficiency.
Solar is cyclical and if it’s not matched up with cyclical demand, it requires a means of storage, which is its own project. The power output it creates is also directly proportional to the footprint it takes up on the ground. Using as much area as it takes to be productive on a large scale often means solar arrays are located far from the load they support, requiring a lot of transmission capability. This challenge is far from unique to solar, however.
Good: Wind is free and there’s a lot of it.
Bad: Wind is cyclical also, and also requires storage. The cycles may also be less consistent than solar. Also, depending on who you listen to, windmills kill birds and blight the landscape with their large white towers.
Biofuels and Biomass:
Good: It uses biological material that we are producing anyway and prevents or reduces certain pollution associated with typical ‘disposal’ of this organic matter.
Bad: Requires proper pollution control.
Good: Water naturally flows from higher elevations to lower, and hydropower is a proven means of drawing power from the potential energy of water accumulated in a reservoir.
Bad: Lots of natural habitat is altered, affecting wildlife.
Good: Heat of the earth is in plentiful supply and naturally regenerates. Small footprint above ground. Near zero emissions. Long life cycles.
Bad: Long construction cycles. Older methods tend to cause the ground to ‘settle’ over time.
Good: Tidal energy is naturally occurring and plentiful.
Bad: No long-term proven successes, offshore construction may present hazards to marine life.