On September 5th 2018 we attended the “Achieving Net-Zero Energy Buildings Workshop” organized by the New Building Institute (NBI) in collaboration with two DC Government agencies: DCRA & DOEE. The conference was held at The University of The District of Columbia’s impressive new student center and was very well attended. The conference started by emphasizing several troubling statistics to those of us in attendance as a reminder of why this topic is so important:
· 74% of carbon emissions come from buildings,
· While the US comprises only 4% of the world’s population, we produce 15% of all greenhouse gas emissions.
Washington DC, the city we call home, has striven to be a leader in sustainability. In 2017, DC was named the first LEED Platinum city in the world. In this spirit, DC has committed to becoming a carbon neutral city by 2050. The built environment will play a critical role in mitigating the effects of climate change. Tommy Wells, the director of DOEE, opened the workshop by saying, “We don’t tear down a lot of buildings in DC. So new buildings must be rock-stars, and we need to learn how to retrofit the existing stock” in order to address global warming, climate change and issues of resilience.
So what is net zero, you might ask? The Net Zero Energy or Zero Net Energy building (ZNE) is defined as: an energy-efficient building that produces at least as much energy as it uses in a year, when grid-supplied energy is accounted for at the source (including primary energy for generation, transmission and delivery to the site).
A study conducted a decade ago revealed that NZE buildings were possible in every climate zone in the US, and today there are many are examples across the country.
Schools are currently the most common NZE buildings by type, followed by offices and multifamily construction.
The main benefits of these hyper efficient building are: reduced greenhouse emissions, increased productivity and well-being of occupants, and Savings (Utility bills).
One of the case-studies presented at the workshop was The American Geophysical Union building, currently under construction right here in DC (200 Florida Ave, NW). This is a conversion of an old building into an exemplar of energy efficiency and modern amenities. The new facility will boast a solar array, a roof garden, a green wall that runs the height of the interior space, dynamic glass shading, radiant cooling ceiling panels and a sewer heat exchange to name a few. The USGBC will be holding tours of the building on October 24th so sign up!
If you happen to be in Virginia, you might want to visit one of VMDO Architects’ pioneering high-performing projects. They gave a presentation on their award-winning net zero elementary school, Discovery Elementary, a recently completed in Arlington, Virginia.
For more examples, NBI has a database of North America’s most advanced energy efficiency commercial projects including zero and ultra-low energy projects.
So what goes into achieving a net zero building? All the presenters at the conference stressed the importance of engaging stakeholders and setting target performance metrics early in the design process (and to define them in the RFP). Once the design team is put together and everybody is on board, owners, occupants, and the design team members should come together to brainstorm potential strategies and technologies in what are called Integrated design Charettes. Iterative energy modeling is critical for hitting those targets. Monitoring building and occupant patterns will ensure that you not only design to net-zero but that your building actually performs at net-zero.
In an effort to be sustainability leader, DC has set some ambitious goals for the future of our city. Clean Energy DC is DC’s Climate Mitigation Plan. It includes DOEE’s Sustainable DC 2032 climate and energy targets. By 2032 all new construction in DC will be (required to be?) Net Zero. Greenhouse gas emissions will be reduced by 100% by 2050. DOEE’s 50/50/50 challenge seeks to cut energy use by 50%, increase the use of renewables by 50% and reduce greenhouse gas emissions by 50%. DCRA will be adopting codes that mandate new residential construction to be net zero by 2020 and new commercial construction by 2026. They also announced that in the coming months they will be introducing “Appendix Z” – an incentivized, voluntary net zero building program for residential and commercial buildings. These objectives together are conceived of as a grass roots effort, driven by the community to encourage early adopters to lead the way and prime the industry for the city’s net-zero goals.
For more information or technical and financial support, the DC government encourages residents to refer to the following resources: