Gradient deploys Window Heat pumps at Providence public housing Tower, unlocking 450,000 kwh in annual savings. April 21, 2026 Building-wide installation at Carroll Tower marks milestone for Clean Heat Rhode Island program and proves a replicable model for multifamily electrification Gradient today announced the completion of a building-wide window heat pump deployment at Carroll Tower, a 194-apartment Providence Housing Authority property, bringing modern heating and cooling to residents for the first time in the building's 50+ year history. The project replaces outdated electric baseboard heating with Gradient All-Weather 120V window heat pumps, supporting Rhode Island's clean energy goals. This $1.25 million project installed 277 Gradient All-Weather 120V window heat pump units across the building's 194 apartments. Preliminary estimates indicate the upgrades could deliver approximately 450,000 kilowatt-hours in annual energy savings, equal to about $94,500 annually for the Carroll Tower, while reducing greenhouse gas emissions by an estimated 219 tons of carbon dioxide equivalent each year. Gradient's All-Weather 120V window heat pumps were deployed in partnership with the Rhode Island Office of Energy Resources, Providence Housing Authority, Abode Energy Management, and Envr Air, as part of the state's Clean Heat Rhode Island program. Each Gradient All-Weather 120V unit is designed for two-person installation and plugs into a standard 120-volt outlet, avoiding the costly electrical upgrades and invasive retrofits that typically slow heat pump adoption in older multifamily buildings. Combined with Envr Air's logistics-driven installation approach, the technology enabled the entire 194-apartment transformation in just 12 days. "Carroll Tower shows what's possible when housing authorities, state agencies, and technology partners come together around resident wellbeing," said Dr. Vince Romanin, Founder and CTO of Gradient. "Providence Housing Authority is proving these projects can be cost-effective, fast, and minimally disruptive - while also improving comfort and safety for residents. That's what makes this scalable: when you can retrofit existing buildings without major electrical upgrades or capital-intensive construction, it becomes something that can work across entire portfolios." Addressing long-standing resident needs. For decades, Carroll Tower residents - many of whom are elderly - relied on inefficient electric baseboard heating that drove up energy costs and struggled to maintain comfortable temperatures. During summer months, residents depended on individual window-mounted AC units that provided limited and inconsistent cooling. PHA's investment in modern heat pump technology addresses these longstanding challenges by providing: * Year-round comfort residents control themselves, including first-time in-unit air conditioning for every apartment * Major energy savings over electric baseboard heating, lowering PHA's operating costs * Modern monitoring and management for improved building operations The project directly supports multiple PHA strategic priorities: energy efficiency and climate response, resident comfort and safety, operational improvements, and strategic partnerships that benefit the community. "This project represents an important investment in the comfort and wellbeing of our residents," stated Melissa Sanzaro, Executive Director of Providence Housing Authority. "Carroll Tower is one of two public housing buildings designated by the U.S. Department of Housing and Urban Development exclusively for the elderly, with an average resident age of 72. The PHA is honored to be a part of this pioneering project that exemplifies how industry collaborators can align their goals and create opportunities to advance initiatives and technologies that enhance the quality of life for vulnerable communities while positively impacting the environment." "This great heat pump project shows how Clean Heat Rhode Island can help modernize buildings that have historically been difficult to retrofit," said Acting Rhode Island Office of Energy Resources Commissioner Chris Kearns. "By partnering with the Providence Housing Authority and industry partners, we were able to deliver efficient heating and cooling technology that improves resident comfort while lowering long-term energy use and emissions." Strategic partnerships drive impact. The Carroll Tower deployment brought together public and private sector partners, each contributing essential expertise: * Rhode Island Office of Energy Resources provided program oversight and funding through Clean Heat Rhode Island, demonstrating the state's commitment to making clean energy accessible in public housing. * Abode Energy Management served as program administrator and coordinated project implementation. * Envr Air developed and executed a streamlined installation approach that minimized disruption to residents while maintaining an aggressive deployment timeline. * Gradient supplied the All-Weather 120V window heat pump units installed. "We're at a moment where the solutions exist, the business models work, and buildings that seemed too old or too complicated to electrify are no longer out of reach," said Jesse Mastro, CEO and Founder of Envr Air. "Carroll Tower proves it's scalable, affordable, and far less disruptive than anyone expected. This is just the beginning." "Abode was excited to help prove that this technology can work at scale, delivering fast, resident-centered electrification at Carroll Tower," said Kristin Dupre, VP of Strategy and Partnerships at Abode. Together, these partners demonstrate how strategic collaboration between state agencies, technology providers, and implementation specialists can deliver meaningful climate action while improving residents' daily lives. Over the next two years, the Carroll Tower project will generate operational data to inform future Clean Heat Rhode Island program design and additional multifamily electrification opportunities across the state. About Gradient Gradient is rethinking building heating and cooling with innovative, sustainable solutions designed for a decarbonized future. Its All-Weather 120V Window Heat Pump delivers year-round performance with high efficiency and easy installation, eliminating the barriers of traditional systems. Backed by a team of industry leaders, including talent from Tesla and Nest, Gradient is committed to redefining heating and cooling for modern buildings while minimizing environmental impact. In addition to venture funding, the company has secured non-dilutive funding from the U.S. Department of Energy, California Energy Commission, NYSERDA, California Strategic Growth Council, and others. To learn more, visit gradientcomfort.com. About Rhode Island Office of Energy Resources The Rhode Island Office of Energy Resources' (OER) mission is to lead the state toward a clean, affordable, reliable, and equitable energy future. OER develops policies and programs that respond to the state's evolving energy needs, while advancing environmental sustainability, energy security, and a vibrant clean energy economy. OER is committed to working with public- and private-sector stakeholders to ensure that all Rhode Islanders have access to cost-effective, resilient, and sustainable energy solutions. About Providence Housing Authority Founded in 1939, the Providence Housing Authority (PHA) provides and develops quality and safe affordable housing opportunities and services to address the needs of Rhode Island residents. gradientcomfort.com is committed to the core values of excellence, accountability, innovation, respect, and equity in all that gradientcomfort.com do. Today, the PHA provides affordable housing to more than 12,000 residents in the City of Providence. PHA operates 2,606 public housing units and administers more than 2,700 tenant-based and project-based Section 8 vouchers which allow low-income families to rent in the private market. PHA hosts a variety of support programs to help its residents and participants meet their wellness, financial, and employment goals no matter what their age or ability. The PHA is a quasi-governmental organization, governed by a Board of Commissioners nine of whom are appointed by the Mayor and two elected from within the Providence City Council, and led by an Executive Director who reports to the Board. About Envr Air Envr Air is a Massachusetts-based company accelerating building decarbonization through "plug-and-play" HVAC solutions. Envr Air specializes in window heat pump installations that convert buildings to clean energy without construction, delivering the most cost-effective electric HVAC conversions on the market. The company's logistics-driven approach enables building-wide conversions in days rather than months. Envr Air serves multi-family property owners, housing authorities, and institutions across the Northeast. Learn more at envrair.com. About Abode Energy Management Founded in 2017 and headquartered in Concord, Massachusetts, Abode Energy Management develops and implements practical programs that drive the adoption of energy efficiency and decarbonization solutions across New England. The company serves homeowners, utilities, and contractors through four core areas of expertise: energy efficiency and electrification programs, technical solutions for residential decarbonization, contractor management and support, and training and workforce development. A proud member of 1% for the Planet, Abode has donated over $600,000 to New England-based nonprofits since its founding, supporting organizations focused on environmental justice and equity. Media Contacts: Gradient Hiroshi Saito [email protected] Providence Housing Authority Chantal Jordan Communications Specialist [email protected]

Gradient, a heat pump startup, has launched Nexus, software that links its window-mounted heat pumps across multifamily buildings. The system allows building managers to set temperature limits while maintaining resident comfort, with one building seeing a 25% drop in energy consumption after implementing controls. The company targets old buildings with aging boilers, particularly in New York City, where its heat pumps provide both heating and cooling without requiring electrical upgrades. Installation takes hours rather than days, as units fit in windows like air conditioners but don't block views. Gradient has deployed its technology in New York City Housing Authority buildings and affordable housing developments. The Nexus system can also reduce power draw during grid stress whilst maintaining comfort, using building data and sensors to identify which units can temporarily decrease consumption.