The Harvard Center for Green Buildings and Cities (CGBC) has completed the retrofitting of its 4,600-sf headquarters in Cambridge, Mass., built in 1924, into a living laboratory called HouseZero, whose design is driven by ambitious performance targets that include nearly zero energy use for heating and cooling, zero electrical lighting during the day, operating with 100% natural ventilation, and producing zero carbon emissions.
Snohetta was this project’s chief architect, and Skanska Teknikk Norway its lead energy engineer.
A prototype, HouseZero has been set up to address a chronic problem within the built environment: inefficient existing structures. The building inventory in the U.S. is estimated to account for 40% of the country’s energy consumption, with 25% of that usage attributed to housing alone. The annual costs of residential energy consumption are enormous: $230 billion for heating, cooling and powering the nation’s 113.6 million households.
CGBC, at the Harvard Graduate School of Design, has embedded hundreds of sensors connected by several miles of wiring within each component of HouseZero, from which it will draw data points that inform its researchers about the building’s behaviors. These data will be the basis of computational simulations for fuel research that could help the Center develop new systems and algorithms that promote energy efficiency, health, and sustainability.
The goal of HouseZero is to create a blueprint for reducing energy demands and increasing cost savings for property owners. “HouseZero challenged us to rethink the conventions of building design and operation to enhance lifelong efficiency and quality of life for occupants,” says Ali Malkawi, founding director of CGBC, and creator and leader of the HouseZero project.
An example of this rethinking is natural ventilation that is controlled by a window actuation system that employs sophisticated software and sensors arrays to automatically open and close windows to maintain a quality internal environment throughout the year. The building itself will strive for best possible comfort. However, Malkawi notes, a window can always be opened manually to ensure individual comfort.
HouseZero’s third floor features a flexible, highly-controlled and monitored experimental space—dubbed the LiveLab—that’s hardwired to the building’s energy exchange system. The space will allow for the testing, swapping, and optimization of new technologies. An immediate goal is to beta test new technologies that can eventually replace the building’s ground source heat pump for peak conditions.
HouseZero is naturally ventilated, and designed to use only natural lighting during the daytime hours. Image: Michael Grimm
The building will also be used to research how structures connect with and respond to its natural environment. Its envelope and materials were designed to interact with the seasons and the exterior environment. The building, according to CGBC, will adjust itself to reach thermal comfort for its occupants.
HouseZero will achieve zero net energy with the help of a rooftop PV array that provides renewable electrical energy for the heat pump as well as for energy required by user equipment. A battery system is employed for night time use and low-sun conditions.
To meet proposed emission cuts of the Paris agreement, HouseZero will offset the hidden emissions generated throughout the building’s anticipated 60-year life cycle, from the fabrication and transport of building materials and construction processes, to maintenance and decommissioning.
The rest of the renovation team on this project included Columbia Construction (CM), Silman Associates (SE), BR+A (MEP/FP/lighting), Bristol Engineering (CE), WindowMaster (BAS/Controls/Natural Ventilation systems), Brekke & Strand Akustikk (acoustrics), Jensen Hughes (code and accessibility consultant), Haley & Aldrich (geotechnical engineer), Syska Hennessy (vertical transportation), Kalin Associates (specifications), Siemens Building Technologies (security systems), Solect Energy (photovoltaic systems), Reed Hilderbrand (landscape architect), Harvard Planning and Project Management; CSL Consulting (project management), and Harvard Graduate School of Design (operations support).
Related Stories
Green | Jun 26, 2023
Federal government will spend $30 million on novel green building technologies
The U.S. General Services Administration (GSA), and the U.S. Department of Energy (DOE) will invest $30 million from the Inflation Reduction Act to increase the sustainability of federal buildings by testing novel technologies. The vehicle for that effort, the Green Proving Ground (GPG) program, will invest in American-made technologies to help increase federal electric vehicle supply equipment, protect air quality, reduce climate pollution, and enhance building performance.
Industrial Facilities | Jun 20, 2023
A new study presses for measuring embodied carbon in industrial buildings
The embodied carbon (EC) intensity in core and shell industrial buildings in the U.S. averages 23.0 kilograms per sf, according to a recent analysis of 26 whole building life-cycle assessments. That means a 300,000-sf warehouse would emit 6,890 megatons of carbon over its lifespan, or the equivalent of the carbon emitted by 1,530 gas-powered cars driven for one year. Those sobering estimates come from a new benchmark study, “Embodied Carbon U.S. Industrial Real Estate.”
Mechanical Systems | Jun 16, 2023
Cogeneration: An efficient, reliable, sustainable alternative to traditional power generation
Cogeneration is more efficient than traditional power generation, reduces carbon emissions, has high returns on the initial investment, improves reliability, and offers a platform for additional renewable resources and energy storage for a facility. But what is cogeneration? And is it suitable for all facilities?
Multifamily Housing | Jun 15, 2023
Alliance of Pittsburgh building owners slashes carbon emissions by 45%
The Pittsburgh 2030 District, an alliance of property owners in the Pittsburgh area, says that it has reduced carbon emissions by 44.8% below baseline. Begun in 2012 under the guidance of the Green Building Alliance (GBA), the Pittsburgh 2030 District encompasses more than 86 million sf of space within 556 buildings.
Resiliency | Jun 14, 2023
HUD offers $4.8 billion in funding for green and resilient building retrofit projects
The Department of Housing and Urban Development (HUD) recently released guidelines for its Green and Resilient Retrofit Program (GRRP) that has $4.8 billion for funding green projects.
Codes and Standards | Jun 6, 2023
California’s new power grid modernization plan furthers ambitious climate goals
California’s new $7.3 billion grid modernization plan is a crucial step in furthering its ambitious climate goals. The board of governors for the California Independent System Operator (CAISO), the state’s grid operator, recently approved a strategy to build thousands of miles of new high-voltage transmission lines.
Multifamily Housing | Jun 6, 2023
Minnesota expected to adopt building code that would cut energy use by 80%
Minnesota Gov. Tim Walz is expected to soon sign a bill that would change the state’s commercial building code so that new structures would use 80% less energy when compared to a 2004 baseline standard. The legislation aims for full implementation of the new code by 2036.
K-12 Schools | May 25, 2023
From net zero to net positive in K-12 schools
Perkins Eastman’s pursuit of healthy, net positive schools goes beyond environmental health; it targets all who work, teach, and learn inside them.
Mass Timber | May 23, 2023
Luxury farm resort uses CLT framing and geothermal system to boost sustainability
Construction was recently completed on a 325-acre luxury farm resort in Franklin, Tenn., that is dedicated to agricultural innovation and sustainable, productive land use. With sustainability a key goal, The Inn and Spa at Southall was built with cross-laminated and heavy timber, and a geothermal variant refrigerant flow (VRF) heating and cooling system.
Office Buildings | May 15, 2023
Sixteen-story office tower will use 40% less energy than an average NYC office building
This month marks the completion of a new 16-story office tower that is being promoted as New York City’s most sustainable office structure. That boast is backed by an innovative HVAC system that features geothermal wells, dedicated outdoor air system (DOAS) units, radiant heating and cooling, and a sophisticated control system to ensure that the elements work optimally together.