MassVent

Modern cooling systems cause planetary heating, with their embodied and operational emissions of carbon dioxide driving a global feedback cycle of climate change. Put simply: as we make ourselves cooler, we make the planet hotter.

The International Energy Agency (IEA) reports that "the use of energy for space cooling is growing faster than for any other end use in buildings, more than tripling between 1990 and 2016 [and] carbon dioxide (CO2) emissions from cooling have tripled since 1990 to 1,130 million tonnes (Mt), equivalent to the total emissions of Japan”.[1] The IEA also notes that this trend will not abate, but grow in the coming decades; even while accounting for the effects of current policies and targets, the IEA projects that the energy requirements of cooling will triple by 2050.[2] This impacts billions of people. 

Active space cooling (heat removal) is today typically provided by various types of air-conditioning systems, with over 1.6 billion currently in use, more than half of which are located in either China or the United States.[3] Cooling units in residential buildings occupy relatively small footprints in homes, usually located in windows or on exteriors with corresponding pipes and ducts hidden in walls, ceilings, or otherwise situated out of sight; however, their modest visual footprint belies their planetary environmental impacts.

Air-conditioning (AC) systems require vast production and use of greenhouse gas emitting refrigerants and rely on fossil fuels during both their fabrication and operation via electricity. AC systems commonly strain power grids, create heat islands, weaken physiological acclimatization, and force many people and communities into what is often termed energy poverty, wherein they are forced to choose between their economic and physiological well-being. That choice is often an impossible one since, for many people, access to cooling is a lifeline. The 2021 report of the Lancet Countdown on health and climate change documented that “heat-related deaths in people older than 65 years reached a record high of an estimated 345,000 deaths in 2019 [and] in the absence of air conditioning, an estimated 195,400 more heat-related deaths would have occurred.”[4] Cooled buildings save lives, but relying solely on electrical systems sacrifices the health of the planet. 

Current research primarily addresses the operating efficiency of individual units and proposing strategies without GHG-emitting refrigerants, but such proposals seldom question the infrastructure of cooling architecture. Existing proposals, policies, targets, and laws all prioritize the fuel efficiency and operational emissions of space cooling but rarely address both the embodied and operational carbon emissions of cooling machinery. However, as the Carbon Leadership Forum and others have determined, there is a responsibility toward the time value of carbon,[5] which makes it imperative to prioritize the impacts of embodied emissions over the potential future savings of operational emissions to meaningfully attenuate climate change.

[1]  Dr. Fatih Birol Executive Director International Energy Agency, The Future of Cooling, 2018

[2] Ibid.

[3] Ibid.

[4]  The 2021 report of the Lancet Countdown on health and climate change: 'Code Red for a Healthy Future'

[5]  https://carbonleadershipforum....

MassVent is a climate-specific (Cfa/Cwa/Dfa), low-carbon, natural cooling and ventilation system designed to be used in residential structures, which make up the majority of buildings in the United States. The solution uses ancient technology of geometry, materiality, and buoyancy through a simple system of components that create natural ventilation and space cooling (heat removal) in buildings, without the need for electricity, refrigerants, or fossil fuels. MassVent is designed primarily for the segment of the housing market in need of resilience retrofits, but can also be designed as a competitive alternative for builders of new housing looking to select a cooling system.

The system consists of two primary components: a horizontal element (trough), and a vertical element (stack). The trough is an earth duct that pre-cools and de-humidifies incoming air with thermal mass and large surface areas, while the stack is a timber, clay, and glass solar chimney that creates air-flow propulsion through a solar-induced temperature and pressure differential. Both of these technologies are based on centuries-old cooling systems and simple principles of heat flow, yet they have been replaced by other mechanized forms of cooling. The novelty of our solution is to re-introduce these concepts in components that can be adapted to existing and new structures. 

The elements can be installed in a single location, or multiple locations, depending on the size, shape, and spatial distribution of a particular building. While the base components are identical, the trough and chimney sizes, openings, and orientations can be tailored to each unique context and cardinal direction, to maximize solar heat gain and thus internal air propulsion. This tactic simultaneously imbues a generic base-system with contextual specificity - something that contemporary cooling systems lack. 

Our solution inverts approaches of traditional cooling technologies - whereas existing methods minimize visual impact at the expense of high carbon emissions and planetary warming, our approach physically integrates low-carbon and carbon sequestering components with building walls to leverage their large surface area and geometry as a building-scale cooling apparatus, allowing the building itself to provide cooled fresh air. This means that in the event of power outages, the building will not become a heat-trap, but will be able to protect its inhabitants from excessive heat.

The individual components can also be integrated into new construction, wherein the horizontal trough is extended and flattened into a full floor slab. Most single-family homes in the U.S. are already built on a concrete slab, and while concrete is relatively low-embodied carbon per kilogram, its overproduction is responsible for a disproportionate percentage of global carbon emissions; our new construction version seeks to replace interior floor slabs with rammed earth and integrated air channels. This version of the system is similar to the retrofit, but allows builders greater flexibility while avoiding the installation of a cooling system.

The primary benefit of the solution is to provide a low-carbon and cost-effective cooling system for both retrofits and new construction that requires zero electricity and minimizes the use of fossil fuels.

There are 140 million housing units in the United States,[1] and approximately 1-2 billion buildings on the planet that fall within the hot and/or humid CfA, Cwa, and DfA climate zones, with countless more to be built in the coming decades. According to the U.S. Census data, the majority (61%) of housing units in the United States are single-unit detached structures, and over 90% of single-family homes being constructed are site-built, wood frame structures of 1-2 stories.[2] The people, the families, and the communities who live in the majority of the hot-climate U.S. building stock (and millions more around the planet) are those for whom this solution is designed. 

MassVent is directed toward many different constituencies, chief among whom are developers, landlords, homeowners, and individual homebuilders. Each of these groups are currently presented with few options for meaningful low-carbon alternatives to space cooling infrastructure. Simultaneously, the National Association of Home Builders (NAHB) documents how costs of framing and finishes have remained consistent or decreased as a percentage of total construction costs over the past decade, while the costs of system installation (mechanical, electrical, and plumbing) have increased.[3] As a result, homeowners are economically incentivized to choose the cheapest and most convenient mechanisms for space cooling, which are also often the most environmentally destructive. While the components of our solution are more expensive than individual heat pumps, our solution is designed to be more cost-effective at building scale because it requires few or, possibly, zero operating costs (other than general maintenance and, possibly, activated louvers), and allows homeowners and builders to avoid comprehensive or expensive mechanical / electrical retrofits. 

MassVent is also tailored towards building professionals such as architects, engineers, and contractors who increasingly prioritize operational carbon emissions, or those that can be deduced through electricity generation and utility bills, at the expense of high-embodied carbon construction and systems. These concerns are revealed by well-known rating systems such as the international Passivhaus and LEED certifications, and legislation such as Local Law 97 in New York City, efforts which meaningfully target operational fuel usage but typically fail to account for the time value of embodied carbon emissions and the imperative to create immediate change. 

With funding from MIT Solve, our prototype will be built in New Jersey, the densest state in the U.S., and a region broadly suffering from significant construction costs and high eviction rates. On a national and international scale, the project site is located on the border between climate zones 4A and 5A (ICC / ASHRAE classification) as well as the border between Cfa and Dfa (Köppen–Geiger classification). These climate zones represent the south and eastern borders of many continents and countries and a significant percentage of the global population, including billions of people living in parts of the United States, China, Brazil, Argentina, Australia, and other regions.

[1] U.S. Census

[2] Ibid.

[3] NAHB

Our team currently consists of three complementary individuals: an architect / builder, a passive design / climate specialist, and a PhD candidate studying natural ventilation and cooling. Each of us worked in the field of architecture and construction where we intimately witnessed the caustic effect of risk-aversion on innovative thermoregulation solutions in the HVAC sector, and resulting helplessness on the part of designers and builders.

As a collective, each of us lives and works in the region and the community where we are building and testing our prototype; our personal as well as professional lives are intertwined in the region and with the people who live and work there. We both represent and tackle on a daily basis the challenges and frustrations facing the design and construction disciplines from whom substantive changes are petitioned to transform our building stock and construction practices, in order to stem the advance of climate change. 

Initial investigations for our prototype began with climate research, housing typology data, surveys of environmental and construction costs, and natural ventilation calculation, each of which we have studied with peers, colleagues, and predecessors. However, this information remains largely locked in academia, and inside relatively modest cohorts of design and building professionals, but is largely absent from everyday construction practices and therefore inaccessible to average homebuilders and homeowners. Every day we witness the discrepancies and barriers between national or international climate policies and the realities of economic and regulatory incentives for retrofits and new construction housing projects. We want to bridge that divide, and offer new possibilities for space cooling directly to design practitioners , builders, and homeowners. 

We are currently experimenting with the design and testing of our prototype to understand the potential impacts (social, ecological, financial) that it can provide in both retrofit and new construction contexts. The next step will be extensive communication with builders, homeowners, and community members to understand the potential efficacy of what we are proposing. We aim for our physical prototype to be the locus of such sessions, with potential future stakeholders being able to physically enter it and, quite literally, feel the cool, fresh air move over their skin, powered by little more than the naturally occurring stack effect, and some carefully calculated mass and geometry.

The Team Lead, Peteris Lazovskis, is a designer, builder, and PhD candidate studying the integration of architectural form with natural cooling and ventilation. But, more importantly, Peteris and all of us live in the region where we are testing our prototype and all of us are engaged in the complicated process of designing, making, and affording homes that might serve as examples of low-carbon, climate-resilient buildings offering people better ways to live amidst the social and ecological obligations and opportunities in this century. 

MassVent is currently in the design and prototype development stage, and therefore does not yet serve any customers; with funding from MIT Solve, our prototype will be built to comprehensively understand its capacity for change as well as the extent of the social, ecological, and financial incentives that it will provide. This will be a critical step towards establishing market parameters by providing invaluable user and performance feedback, and will accelerate our progress on the path to commercialization.

We have not yet applied for or received any support from institutions, companies, or individuals beyond the members of our team. We are applying to MIT Solve to introduce a radical new method of building cooling to builders and homeowners, to the community of sustainable building design thought-leaders, and to the wider network of clean-tech entrepreneurs. An impactful demonstration is important, as MassVent is a marked departure from dominant thermoregulation strategies.These typically rely on high-energy and thus high-carbon chemical and mechanical components, to achieve large temperature differences within a small product volume. To reduce operational energy, we have diverted complexity into the math behind the geometry and spatial configurations which, while necessarily increasing mass and surface area, are in turn made of low-embodied energy materials. A full-scale one-room demonstration is thus an ideal first step, allowing us to prototype each flowpath junction without having to build out a full-house system. 

The amount of financial support provided by MIT Solve is well-matched for such a prototype, and will enable us to present MassVent with a strong physical and functional presence. Our team is lean and ready to move fast, and this funding will accelerate the momentum of our prototype development, while giving us a logistical and advisory framework within which to operate. We anticipate spending the majority of the funding on construction materials, with the rest split between monitoring devices, specialty equipment and hosting several community engagement sessions periodically throughout the construction and testing phases. Our team is well versed in construction, and we expect to perform the labor ourselves, with access to University resources nearby. 

In conjunction with prototype construction and monitoring, we aim to tap into the industry connections provided by the MIT Solve Program. Our team’s combined professional experience has shown that the established building thermoregulation industry is highly risk-averse, often requiring high Technology Readiness Level (TRL) and near-market-ready demonstrations before funding or licensing new technologies. Meeting with key industry leaders will thus give us a better understanding of the critical areas requiring de-risking. Similarly, while each of us has deep knowledge of our professional practices, we have relatively little experience navigating the myriad challenges of solutions beyond the scale of a single project. As such, we would greatly benefit from advisory support on the business, legal and logistical side of how to efficiently plan the next steps of evolving a radically non-standard cooling solution such as MassVent.