Getting to Zero (Zero Energy and Emissions Buildings)

Description: Addressing community building and housing stock is a critical element of planning for and addressing the underlying causes of climate change. It is also an effective way to improve resilience, lower operational costs, and increase the value of a community’s building assets.

Buildings represent 40% of the energy used in the U.S. and 39% of carbon emissions, according to the New Buildings Institute’s guide to talking about carbon neutral buildings (see link below). Emissions from buildings are classified as either operational carbon or embodied carbon. Operational carbon in buildings powered by fossil fuels is generated by HVAC, electric appliances, lighting, electronics and electric water heaters, gas appliances and gas water heaters, as well as refrigerant leaks. Emissions related to operational carbon are primarily generated and released during electric power generation. Embodied carbon refers to emissions associated with building materials over their life cycle from extraction to the end of useful life. Zero energy buildings eliminate operational carbon by maximizing energy efficiency, prioritizing on-site renewables and then utilizing off-site renewables for any remaining energy needs. Zero carbon or carbon neutral buildings eliminate embodied carbon as well as operational carbon.

The New Buildings Institute lists 198 verified zero energy buildings in the U.S. across commercial and multifamily sectors, as well as 620 emerging buildings that have a goal of zero energy but do not yet have 12 months of operational data to verify their performance. Among the zero energy buildings in the U.S. are: Bullitt Center (a commercial office building in Seattle, WA), Hunters Point (a residential housing development in Bradenton, FL) and Discovery Elementary School (an elementary school in Arlington, VA that uses zero energy design and operation as a teaching tool). Zero carbon buildings are more difficult to verify, requiring more information and continual tracking to verify their performance.

Examples of actions local leaders can take related to zero energy and zero carbon buildings that reduce emissions and engage community members include:

• Establishment of building performance standards (BPS) by local leaders. According to the Institute for Market Transformation (IMT), a BPS is “a policy that sets specific deadlines for existing public and private buildings over a certain size to achieve quantified standards of performance across one or more metrics—such as energy use, water use, and/or greenhouse gas emissions. The standards become more ambitious over time, driving continuous, long-term improvement in the building stock.” See IMT’s Building Performance Standards resources linked below for IMT’s existing guidance on building performance standards. A second IMT link provides a guide to Developing and Implementing a BPS.
• Establishment of building codes promoting or requiring energy efficiency measures such as a high-performance building envelope; efficient equipment including heat pumps, smart building controls, and energy-efficient lighting; and the electrification of gas appliances. While these types of building codes do not address whole building performance, they can reduce energy consumption and emissions and may often be enacted more easily and faster than BPSs.
• Promotion of on-site renewable electricity generation, such as rooftop solar panels and battery storage in existing building stock.
• Establishment of building codes requiring the installation of on-site electricity generation such as rooftop solar panels and battery storage in new construction. In addition, architects and builders should be educated on the importance of building placement and design measures to facilitate use of on-site renewables.
• Support and promote selection of provider options for 100% renewably generated electricity to meet a building’s energy needs not met by on-site renewables. Such options are typically available from investor-owned or municipal utilities, community solar projects or, in some locations, Community Choice Aggregators.
• Establishment of building codes promoting or requiring the use and reuse of low-embodied carbon materials in new building construction. Construction materials account for 11% of global carbon emissions, according to New Buildings Institute. Thoughtful material selection can reduce embodied carbon and related emissions.

The above examples and linked resources can help activists and local government officials plan for and create policies that improve community resilience, lower building operational costs, and increase the value of community building stock – all while simultaneously reducing carbon emissions and working to mitigate climate change.

Goal: Reduce energy use and emissions generated by buildings