ACG Board Member Charles Jackson, CMTA, Inc. Discusses Achieving Net Zero in Retrofit Magazine
In today’s climate, there has been a more considerable shift in focusing on the sustainability of our buildings. With increased decarbonization and energy-performance standards focusing on reducing greenhouse gas emissions and lowering buildings’ energy use intensity (EUI), federal and state mandates require buildings to be net zero within the next 30 years. Buildings are designed to last past that timeframe, so it only makes sense to start looking toward net zero now. Net-zero buildings have become a realistic option and provide many additional incentives that more than justify some additional upfront costs.
To achieve net zero for a building takes the entire project team. As this method has become widely popular, guidelines are ever developing. For example, the Department of Energy and ASHRAE have developed the National Definition of a Zero Emissions Building. LEED has developed the LEED Zero Program Guide for carbon and energy. From a commissioning standpoint, these regulations help us ensure the project team moves forward in the right direction from the design, construction and operations perspective.
Envelope design and equipment selection will make the most impact on the performance of your building. It is essential to ensure energy modeling is done early throughout all design phases with targeted EUI goals. Building orientation and window selections are crucial. Equipment selection focuses more on high-efficiency equipment and understanding the geographical area and space available; for example, utilizing geothermal heat pumps, which take advantage of the Earth’s constant temperature to heat and cool buildings, could be a suitable option. Decreasing your EUI to a level low enough that you can supplement the remaining with renewable energy is also a key design strategy for achieving net zero. Your control strategies are also key in ensuring the building operates efficiently.