As more and more home builders showcase energy efficient construction, Harvard is tackling a much tougher problem. The University’s “Center for Green Buildings and Cities” is looking for ways to retrofit older homes for zero energy consumption at a new living lab along the edge of its campus. The lab is a pre-1940’s home in Cambridge, that doubles as the Center’s headquarters, and is now so energy efficient, it doesn’t need an HVAC system.
The home, called HouseZero, is designed to reduce energy consumption to zero or “almost” zero. It is equipped with energy-conserving devices and materials, and has hundreds of sensors connected by about five miles of wires to monitor energy performance. Project researchers say it’s a first-of-its kind project that could set new standards for ultra energy-efficient existing homes. (1)
Windows Operate for Efficiency and Health
One of its many features are windows that open and close on their own. The upper half of the windows operate automatically if the sensors detect unhealthy or uncomfortable conditions. The lower half of the windows can be operated manually, by humans.
The man who created HouseZero is Ali Malkawi, an architect and an artificial intelligence expert. He says, “The building predicts what the future is going to hold in relation to the temperature, so it’s based on weather forecasts, and adjusts the windows accordingly.” The occupants don’t have to worry about temperature adjustments, although they can override the automatic controls.
But, it’s not only a matter of temperature control. Malkawi doesn’t just want energy efficient automation. He also wants the interior environment to be healthier. For example, the windows will open for fresh air when the CO2 levels get too high. He says, “We typically have buildings that are sealed. This building is very much connected to the outside.”
Natural Ventilation System
Other features include a solar vent that rises along the side of the home like a glass elevator shaft, to help circulate air from floor to floor. There are also materials that help control humidity, better insulation around the outside of the house and along floors and stair wells, and a heat pump in the basement for extreme weather conditions during the winter.
Windows have been enlarged to allow more natural light during the day, and to eliminate the need for daytime lighting. Skylights with good insulation were installed. The windows also have cowlings to reduce summertime sunshine and heat. And, battery storage from solar roof tiles provide electrical needs when the sun isn’t shining.
The Harvard Gazette says, the home operates with “nearly zero energy for heating and cooling, zero electric lighting during the day, operating with 100% natural ventilation, and producing zero carbon emissions.” Project participants are hoping to redefine how a living space can interact with its inhabitants and its natural environment in an efficient and healthy manner. (2)
Bringing HouseZero Concepts to Market
Malkawi and his team also have lofty goals. Malkawi says, “HouseZero’s flexible, data-driven infrastructure will allow us to conduct further research that demystifies building behavior, and design the next generation of ultra-efficient structures.” HouseZero is operated as a non-profit part of Harvard and will make the data available to the public.
Of course, it’s one thing for a University team to convert an older home into a model of energy efficiency, and quite another to mass market the idea. The project website addresses the issue saying, “We hope to prove that HouseZero’s approach is replicable.” It says, “Some of HouseZero’s upgrades are solely required to transform the building into a functional office for up to 20 researchers and staff, but most enhancements to the existing building are viewed through the lens of the renovation market.”
Researchers are hoping that some of the best features of HouseZero will be easy for other property owners to implement, for homes and businesses, although it’s obviously still a work in progress. They just launched the project a few months ago and are just beginning their experiment.
In addition to sensors used for data collection and building operation, the third floor has been turned into a configurable lab, or lab within a lab. They call it a “LiveLab” because it’s used to test different technologies and devices that can be easily swapped out. They hope to develop something in the LiveLab that will replace the heat pump eventually.
The Future of Energy Efficient Older Homes
This kind of work could set new trends for existing homes and other structures, which account for the bulk of all properties. It’s the new buildings that are being designed for green standards. Harvard hopes to provide answers for existing structures, with an overarching goal to fight climate change. We have many inefficient older homes and other buildings which use vast amounts of energy.
Project managers say, they hope to prove that it’s possible to retrofit older buildings to meet the same rigorous energy standards of new energy efficient structures. Even if building owners can’t incorporate all of the things they are doing in HouseZero, researchers say applying one or two of the features could reduce energy use and costs.
HouseZero is a project to watch as we address climate change issues. It could provide us, at some point, with solutions for energy efficiency in older homes. Malkawi says, “HouseZero challenged us to rethink the conventions of building design and operation to enhance lifelong efficiency and quality of life for occupants.”