“How can we make a building that uses no energy?”
Net zero energy usage in buildings can mean two things. Either all of the energy consumed by the building is met through self-generation or the building itself uses no energy! The latter is the foundational idea behind Passive Buildings. Passive buildings are edifices that obtain all of their heating and lighting through natural means. This means that such buildings have lots of large windows to let natural sunlight in, are superinsulated, and employ passive solar design. Therefore, these buildings can skip the need for complex lighting and HVAC. Passive buildings are amazing to experience and should be enjoyed by everyone in my opinion.