Off the top of my head: Passive solar design, smaller homes, solar power, wind power, more efficient methods that use less water or energy to accomplish someth

Off the top of my head: Passive solar design, smaller homes, solar power, wind power, more efficient methods that use less water or energy to accomplish something, public transit, storm/disaster prep and clean up type things, storm resistant housing such as geodomes and smart city stuff. I am sure there is more.