Globally, it’s getting both warmer and more humid. Heating, ventilation, air conditioning, and refrigeration (HVACR) is increasingly essential for the functioning of modern society. Human health and comfort depend on it. Unfortunately, the proliferation of climate control technologies is increasing energy consumption along with greenhouse gas emissions (GHGs) as a result. The positive feedback loop of a warming planet leading to increased AC use leading to a warming planet presents a major challenge to our net-zero climate ambitions as well as our desire to increase living standards worldwide. Clean Energy Ventures (CEV) believes that technological innovations in HVACR, which improve efficiency and reduce energy use, can play an important role in decarbonizing the built environment.
Cooling and refrigeration accounts for about 20% of total electricity use in buildings and 10% of all global electricity consumption today. HVACR already plays a significant role in electricity demand and will be one of the biggest drivers of additional electricity demand over the next few decades. The electricity demand from air conditioning is especially concerning for peak loads, which stress grid infrastructure and can result in dangerous power outages during heat waves. Furthermore, peak demand is typically served by more emissive power sources like natural gas peaker plants. Combined with high global warming potential (GWP) refrigerant leakages, cooling is responsible for about 4% of global GHG emissions. For context, this is double the entire aviation industry.
On top of the emissions from cooling buildings, heating also has a massive carbon footprint. In 2022, the direct emissions from the combustion of fuels for space and water heating accounted for 2.4 gigatons of CO2 emissions. While off-site production of electricity for heating is also responsible for significant emissions today, the CO2 intensity of heating per unit of floor area has been modestly coming down over the last two decades due to stricter building energy codes and the electrification of some heating via heat pumps. Heat pumps can obviate the need to burn fossil fuels to generate heat. The continued proliferation of renewable electricity will further reduce the carbon footprint of heat pumps compared to natural gas furnaces and boilers. To date, the average year over year reductions in CO2 intensity of heated buildings is not large enough to stay on track with the IEA’s Net Zero Emissions by 2050 (NZE) Scenario.
Despite HVACR’s significant contributions to carbon emissions, the sector hasn’t received as much attention nor investment compared to others like clean electricity generation and transportation. We expect robust demand for HVAC fueled by a combination of increased: global living standards, energy efficiency mandates/incentives, global temperatures and humidity, and attention to indoor air quality. As HVAC unit costs come down, the demand in developing countries, many of which are in the hotter global south, continues to accelerate. Forecasts project that there will be ten new AC units sold every second for the next thirty years.
The more things change, the more they stay the same
Willis Carrier’s first electrical AC unit dates back to the turn of the 20th century. While initially designed to solve a humidity issue in the publishing industry, the underlying technology’s ability to control both humidity and indoor temperature in residential and commercial settings was realized over the next few decades. The same fundamental working principles of a device invented in 1902 continue to underpin today’s air conditioners though the efficiencies have steadily improved through the incorporation of better refrigerant materials, electronic controls, etc.
Today, humidity removal surprisingly accounts for more annual GHG emissions (599 megatons of CO2e) than temperature reduction (531 megatons of CO2e). As ventilation and insulation in our buildings continue to improve, the fraction of emissions associated with humidity loads will increase even more in the future. To break the vicious cycle of increased AC use and global warming, we need to rethink how we manage moisture in the air. This is where Transaera comes in.
Revolutionizing HVAC for sustainable buildings
Transaera is commercializing energy efficient HVAC technologies that utilize a novel class of materials called metal-organic frameworks (MOFs). MOFs are crystalline solids with tunable structures which allow them to selectively adsorb water from the air. Transaera has developed methods to apply MOFs as coatings and incorporate them into HVAC systems. Their first product is a Dedicated Outdoor Air System (DOAS) for commercial buildings. Combined with a unique system architecture that utilizes waste heat generated by the system itself for regeneration, i.e., releasing the captured water from the MOF sorbents to the outside, Transaera’s DOAS dramatically improves dehumidification efficiency resulting in 30-40% lower overall energy consumption in buildings compared to today’s HVAC systems.
While CEV has examined many other approaches that utilize liquid or solid desiccants to remove humidity from air streams, Transaera stands out due to the unique combination of energy efficiency and low-cost hardware that is simple, scalable, and in a form factor already familiar to the industry. Given the historical market adoption challenges associated with the commercialization of novel technologies in HVACR, the value of selling a box that looks like the boxes ubiquitous across commercial rooftops today should not be overlooked.
Transaera is planning to replace a portion of conventional rooftop thermal units (RTUs) on top of buildings with their DOAS. With Transaera’s system handling moisture removal, the remaining RTUs can operate more efficiently and thus both electricity consumption and the overall number of required HVAC units goes down. On top of the cooling benefits enabled by better humidity management, Transaera’s system is a heat pump and thus can provide heat in winter months. The energy savings of heat pumps with Transaera’s technology make heat pumps attractive for year-round heating and cooling, even in locations with low-cost natural gas. While dehumidification isn’t as useful in the winter, the dramatic energy savings in the summer make it the lowest cost option for year-round heating and cooling systems across a wide range of geographies and climates. Combined, this leads to fast payback periods, improved comfort, economical building electrification, and 3.20 gigatons of cumulative emissions reductions by 2050.
Cool product; cool team
The genesis for Transaera’s technology extends back to the MIT chemistry lab of Professor Mircea Dincă. While the Dincă Research Lab has now moved from MIT to Princeton, Transaera has also shifted focus from the discovery and synthesis of novel MOFs tailor-made for the adsorption and desorption of water vapor in air to the utilization of MOFs within novel energy-efficient commercial HVAC systems. Cofounder and CEO Sorin Grama has led the company’s transition out of the lab and onto the rooftop. He’s an impact-driven, serial entrepreneur who previously helped commercialize a novel refrigeration technology enabling safer and more reliable milk chilling and transport in locations like rural India with unreliable grid access. Complementing Sorin is cofounder and CTO Ross Bonner, the lead inventor of Transaera’s AC system designs. Ross has an impressive mechanical engineering pedigree from MIT and GE Aviation.
On top of founding two HVACR companies, Sorin also cofounded Greentown Labs, the world’s largest cleantech incubator. As successful commercialization requires interfacing with a wide range of customers and partners up and down the value chain, CEV is excited to partner with Sorin and the entire Transaera team to revolutionize how we heat and cool buildings. We believe Sorin’s successful track record of fostering a climatetech community and driving early partnerships with large industrials will directly translate into win-win partnerships with HVAC OEMs and energy service companies (ESCOs). Rounding out the partnership theme, CEV is investing alongside a strong investor syndicate including MassMutual Ventures, Energy Impact Partners, and Clean Energy Venture Group. We’re excited to be working closely with great entrepreneurs and investors to help decarbonize the built environment!
