There has been a great deal of press about California’s recently adopted mandate that all new homes must have solar power beginning in 2020. What has been missed is that this new rule supports California’s very progressive goal that all new construction attain net zero energy use for residential buildings by 2020 and commercial buildings by 2030.
We’ve been highlighting Project Drawdown’s strategies for fighting climate change since the beginning of year, including green roofs, cement, and the number one solution to global warming, reducing air conditioning refrigerants. The majority of these solutions are focused on a larger scale involving urban planning and global initiatives, but Project Drawdown also has actionable items for individuals and local groups. This year, Project Drawdown and the Northwest Earth Institute (NWEI) debuted the Drawdown EcoChallenge to spur action on these items.
Buildings account for 32 percent of all energy use and 19 percent of energy-related greenhouse gases, according to Project Drawdown, a number that will increase as the global population urbanizes. Heating and cooling requires energy pulled from either natural gas lines or the electric grid, and buildings of all ages are subject to energy loss through gaps in the building envelope or during operations, such as occupants leaving on lights or electronics.
District energy systems (DES) for heating and cooling, particularly in dense urban areas, are a key vehicle for increasing sustainability. Although some forms of DES have existed for over a century, worldwide use is growing, and the technologies they employ are evolving. Project Drawdown ranks district heating, a form of DES, as number 27 in its 100 solutions to global warming. While district energy systems are being used throughout the United States, there is much room for growth and more needs to be done to promote their advantages.
Green roofs - and other green building components such as green walls - provide a host of benefits: aesthetic improvement, stormwater management, heat island reduction, increased biodiversity, and building cooling. Though not yet ubiquitous, a city building with a landscaped, accessible roof is now considered a desirable amenity that promotes a healthy workplace and provides cost-effective cooling benefits.
Project Drawdown ranks green roofs and cool roofs as #73 in their list of solutions to global warming, with an anticipated 0.77 gigaton reduction in carbon dioxide and $988.46 billion in operational costs by 2050. The Project Drawdown impact statement is as follows: