This document discusses the benefits of renewable energy sources in buildings. It outlines various renewable energy sources like solar, wind, hydropower, biomass, and geothermal energy. It notes the advantages of renewable energy being unlimited, clean, and not producing carbon dioxide emissions. The document highlights that renewable energy sources can provide enough energy for buildings in a way that is not noticeable to occupants while being environmentally beneficial. Specific benefits mentioned include using solar power and geothermal energy for heating and biomass for producing heat, cooking gas, and biofuel.