Enter: Building jackets. A growing number of jurisdictions across the US, including the New York State Energy Research and Development Authority (NYSERDA), are embracing whole-building retrofits using prefabricated insulated facades that are doled out by a Dutch non-profit called Energiesprong as a way to neutralize residential emissions at scale.
The public-private initiative, which launched in Holland in 2013 and now operates across Europe, is an effort to drastically reduce the country’s building emissions in service of a national goal to cut greenhouse gas emissions by nearly 50 percent from 1990 levels by 2030. The Netherlands is currently striving to enhance energy efficiency across 1.5 million homes and 1 million utility buildings; Energiesprong is moving it closer to this goal by converting existing social housing to produce net zero emissions.
The idea is simple: Upgrade buildings and cut down on energy waste by attaching external building coats, rooftops, solar panels and zero-emissions heat pumps to buildings in one go. Execution, however, is slightly more difficult: This type of retrofit can be expensive up front, and the market is still young, so demand is minimal and expenses are high. Without government mandates or incentives, securing mass retrofit buy-in is tough.
So, Energiesprong developed a whole-building solution, worked with materials manufacturers, the government, and affordable housing associations to secure participation for 11,000 homes across Holland at the start, locking in an affordable price and establishing a business case for mass retrofits. To date, the company has installed nearly 5,000 between Europe and the US; another 22,000 are in the works.
“When we started a couple of years ago there were not really renovation packages for a whole house; there would be somebody coming in to do some insulation, another party would do some solar panels, but it was all pretty much stacking existing solutions on top of each other, and adding price,” said Sanne de Wit, head of ideas at Energiesprong. “We thought we needed renovation packages from companies that would look at a whole house instead of just a piece of the building.”
he non-profit works with a number of manufacturers, but each building facade is produced similarly. They’re built in a factory, complete with windows, doors and finishes, and are then transported to installation sites in one piece, where they’re attached to a home’s exterior, covering gaps and limiting leaks.
The home envelopes are installed alongside electric heat pumps and insulated roofing that’s topped with solar panels. The objective is to reduce a home’s emissions in two ways: first, by converting its power source to renewables, and second, by limiting how much energy it wastes.
Building jackets tackle the important element of cost when it comes to retrofits. Every home has flaws that impede its efficiency—like cracks in walls or windows that release heat or let in drafts. These typically worsen with time and wear, and can become a money and energy suck if not addressed directly; for low-income homeowners, they can lead to utility debt, which Americans owe on the scale of $35- to $40-billion. Weatherizing a home, or fixing each of these flaws, requires going one by one, typically internally: Installing double-pane windows, sealing leaks and upgrading a home’s insulation or its heating and cooling systems, for example.
This process is vital to curbing residential emissions, but it’s piecemeal and burdensome compared to installing a building jacket, which addresses structural flaws in one fell swoop. Energiesprong’s building facades turn a process that normally occurs in a matter of weeks or months into one that takes a few days and doesn’t require the resident to leave.
“Instead of ripping out the walls on the inside, what if you just came around the outside?” said Thomas Osdoba, senior advisor at Climate-KIC Holding, a public-private climate innovation incubator that provided seed funding for Energiesprong in its early stages.
The non-profit now has projects on the move in Holland, the UK, France, Germany, and Italy, starting with affordable housing, which is relatively homogenous and therefore easy to apply upgrades to en masse. It’s also a demographic that stands to benefit the most from utility savings and building upgrades, which De Wit believes have improved the quality of life for Energiesprong renovation recipients.
“People in a low-income situation get a house that feels like a new house again,” she says. “It was actually really nice, because people really felt like they were living in a new build house.”
The success of Energiesprong inspired the development of a similar project in New York, RetrofitNY, which aims to bring a “large number” of the state’s affordable housing units to net zero energy use by 2025. The program is currently seeking participation from building owners and product manufacturers, but the end goal is to facilitate widespread retrofit adoption by encouraging innovation, driving demand and reducing costs for net-zero building updates.
Osdoba is heartened by local initiatives like New York’s, he said, noting that scaling up retrofit solutions is less about innovation and more about financing and buy-in. Achieving building emissions reductions at the scale necessary to curb the climate crisis will require substantial public investment, like that which the Dutch government made in launching Energiesprong.
“We've built up enough evidence about the benefits of improving our buildings performance from an energy perspective; we have enough evidence about how we can intervene to make our energy systems move towards carbon neutral over the next 10 to 20 years,” he said.
The US government, for its part, has acknowledged the importance of weatherization for combatting the climate crisis. It promoted retrofits through cash assistance funds like the Weatherization Assistance Program (WAP), which doles out financing for home updates to 35,000 low-income households across the US each year and saves an annual average of $283 per household on heat and electric costs.
The Biden administration is also taking aim at increasing retrofits using funding from the Infrastructure Bill, slated to come to a vote in the Senate this week. And in March, 2020, the Department of Energy published a report on the feasibility of programs like Energiesprong’s in US contexts, noting that there’s substantial market opportunity for whole-building retrofits across the country.
But these initiatives are nowhere near what it would take to accomplish net zero residential emissions across the country, and Osdoba says giving every building in America a jacket will require buy-in at all levels. He suggests adopting a public-health style approach: Mandate the adoption of interventions at scale starting at the local level. Solutions like Energiesprong’s make this easier to do.
“We need to do this for everybody,” he said. “Everybody benefits, this is good for everyone. Let's just take that model on.”