Energy conservation Green buildings frequently contain methods to decrease energy consumption, including both the embodied energy necessary to extract, process, transport, and install building materials and the operational energy required to supply services such as heating and power for equipment. Energy-efficient design can also reduce a building's environmental impact by reducing its lifetime energy demand and minimizing its contribution to climate change. The most obvious way that green buildings conserve energy is through their use of less harmful materials. For example, wood is a renewable resource but it takes time and effort to grow trees, so using concrete instead allows us to use our resources more efficiently. In addition, green buildings are typically constructed using materials that retain heat or cold easily, so they don't need to be heated or cooled during extreme temperatures. This can have a significant effect on your city's energy bill because heating or cooling empty spaces increases your carbon footprint. Some ways that green buildings consume less energy include: Solar panels can be used to generate some of your building's energy needs. However, solar panels require direct sunlight which may not always be available, so they aren't always effective at conserving energy. High-efficiency heating and cooling systems use much less energy than traditional systems.