A net zero building is one that has zero net energy consumption, producing as much energy as it uses in a year. In some months it may generate excess electricity through distributed renewables; at other times it may require electricity from the grid. On balance, it is self-supporting. Net zero buildings are more resilient during disasters and blackouts, are more carefully designed by necessity, and generally have reduced operating costs.
Designing a net zero building means seeing a building as a system and addressing the sources of energy use. There are multiple ways to reduce a building’s energy loads, including:
- Maximum insulation,
- Electrochromic glass,
- Passive solar design, and
- Advanced heating and cooling.
Net zero buildings were once a novelty, but are becoming more commonplace, as architects roll out extraordinary buildings across the world. There is now a Walgreens drugstore in Chicago that is a net zero building. Net zero neighborhoods, districts, and communities are also being designed and constructed. Newer net zero buildings push the margins further: zero water and zero waste. They harvest rainwater and process sewage on-site into compostable forms.
There are no numbers at the top of this page because net zero buildings are a mosaic of separate solutions. They draw on high performance glass, cool roofs and green roofs, efficient heating, cooling, and water systems, better insulation, distributed energy and storage, and advanced automation. All are treated individually in our analysis.