Do Renewables Have a Carbon Footprint?

Earlier this year, the director and filmmaker Michael Moore released a documentary titled "Planet of the Humans." Through various interviews with people involved in the renewable energy industry, the film claims that the carbon footprint of the most common renewable energy technologies such as solar, wind, and especially biomass burning is comparable to that of fossil fuel sources of energy. While the film received a tremendous amount of criticism, it did raise several valid questions. This line of thought is often avoided by people involved in the renewable energy movement.

Much research has shown that the life-cycle greenhouse gas emissions of renewable energy sources are generally lower than fossil fuels. However, unlimited demand for any energy will inevitably cause problems to surface. For example, lithium mining to power millions of home batteries and electric cars connected to rooftop solar panels comes with enormous environmental costs. The documentary mentioned above, despite some rather outlandish claims, did its job. It forced its viewers to grapple with the need for restraint and limitation in our demand for energy sources, even if they are renewable.