This week, leaders from around the world will gather in New York City for Climate Week NYC to accelerate action on one of the most urgent challenges of our time. The Engine is proud to be among the attendees, joined by representatives from current and alumni Resident companies including Mantel, Osmoses, Rock Zero, Macrocycle, OpenStar Technologies, and Helix Carbon.
These teams are advancing climate solutions that are as ambitious as they are necessary. Yet, the stakes have never been higher, as federal grant funding and climate incentives become increasingly uncertain. The path to a sustainable future will not be defined by a single breakthrough, but by a mosaic of complementary approaches — and by an ecosystem that ensures these breakthroughs have the support and resources to reach the world.
Roughly 45% of companies in The Engine’s Residency program are commercializing breakthrough solutions that affect climate and planetary health: tapping into new sources of clean energy, decarbonizing industries, creating circular economies, and unlocking sustainable sources of the critical minerals necessary for the energy transition. Below are just a few examples of the bold solutions that The Engine’s current and former Residents are building towards meaningful impact.
Unlocking Limitless Clean Energy
The shift to renewable energy is essential to decarbonizing the economy. But current sources, including wind and solar, have their drawbacks. Energy output is intermittent, dependent on the weather and time of day, and requires large tracts of lands with negative impacts on biodiversity. Fusion energy, on the other hand, promises limitless clean energy without the downsides of conventional renewables — if it can be commercialized at grid scale.
The Engine is taking a leading role in supporting grid-scale fusion so it becomes a reality. In 2018, one of our early Resident companies was Commonwealth Fusion Systems. Now, CFS will build the world’s first grid-scale fusion energy plant in Chesterfield County, Virginia, and has secured a 200MW offtake agreement from Google. CFS isn’t alone: current Residents Cambridge Heavy Industries and OpenStar Technologies are pioneering their own unique approaches to fusion energy.
Beyond fusion, geothermal energy is available in inexhaustible quantities beneath our feet and holds promise as another cheap alternative to fossil fuels; the challenge is drilling deep enough to harness it. Conventional drills used for fossil fuels cannot drill deep enough without melting, limiting current extraction to places where volcanic activity brings the heat close to the surface.
Quaise Energy, another alumni of The Engine’s Residency program, is solving this problem with a platform that vaporizes boreholes to reach unprecedented depths. Think of it like a microwave oven, only instead of using a microwave frequency that heats water, Quaise uses high-power millimeter waves that can melt rocks. Critically, the approach uses the same established infrastructure of the fossil fuel industry, enabling a faster energy transition. The company recently completed its first field test, vaporizing a 100-meter hole through solid granite. Quaise will host additional live public demonstrations at its Texas field site this fall.
Tapping Sustainable Sources of Critical Minerals
The energy transition will require not only new sources of energy, but also critical minerals — lithium, cobalt, copper, rare-earths — to support electrification. But today, mining and refining these minerals comes with severe environmental consequences, including high carbon emissions, ecosystem destruction, and toxic waste streams. Several current and alumni Resident companies at The Engine are shifting this paradigm, commercializing new technologies to reduce both the cost and environmental impact of mineral refining.
Rock Zero is pioneering a chemical process to extract minerals like lithium from rock, circumventing the conventional high-temperature roasting step to reduce CO₂ emissions, energy costs, and hazardous waste streams. In contrast, SiTration is developing a silicon membrane technology that can efficiently filter out critical minerals from existing waste streams, reducing chemical waste. They’re not alone: BlueShift and Lithios are also building electrified processing systems that reduce the financial and environmental costs of critical mineral extraction. BlueShift closed their pre-seed funding round earlier this year, enabling the team to begin construction on their pilot facility in Boston Harbor.
Another Resident company is turning to an unconventional source of critical minerals: cities. Using a combination of robotics, AI, and advanced material science, Mobiüs Industries aims to recover high-value materials from electronic waste, appliances, and industrial scrap. Their proprietary system extracts, sorts, and refines raw materials with minimal human intervention. The process could unlock a circular economy for critical minerals with 95% less energy consumption than traditional mining, creating a more resilient domestic supply chain.
Improving the Economics of Plastic Recycling
The plastic industry accounts for nearly 6% of global CO₂ emissions and creates enormous volumes of waste. Over 5 million tons of plastic contaminate our waters every year. Today, only 9% of global plastic waste is recycled, and most of the plastic waste collected for recycling ends up in landfills anyways. Existing recycling technologies are simply too low in quality or too expensive to be a viable replacement for virgin plastic production at scale.
MacroCycle aims to change this, pioneering a sustainable, zero-carbon upcycling process to create a circular plastic economy. Their patented technology can take PET and polyester waste of any quality and restore it to brand-new conditions, at cost parity and with 80% lower energy use than traditional plastic manufacturing processes. The team closed its seed funding round in March and are already putting their ideas into practice, upcycling plastic waste generated by other Resident companies in their lab space at The Engine.
Decarbonizing Heavy Industry
Heavy industry — including steelmaking, cement production, and chemical manufacturing — accounts for nearly 40% of global CO₂ emissions. In many cases, decarbonizing these industries isn’t as simple as switching to renewable energy sources; they require burning coal or other fossil fuels as part of the manufacturing process.
To break down how Tough Tech companies are decarbonizing these critical industries, let’s start with iron and steel, responsible for 7% of global carbon emissions. The Engine alumni Boston Metal have invented a way to produce steel without coal. The technology, known as Molten Oxide Electrolysis (MOE), uses renewable electricity to convert iron ore into liquid metal in an electrolyte solution. Not only is MOE emission-free, it’s cost-effective and scalable, and can be used to recover other critical minerals as well.
Sublime Systems, another alumni, are using a similar electrochemical technology to decarbonize cement production, currently responsible for 8% of global carbon emissions. The company announced plans to build its first commercial factory in Holyoke, MA last year, and has completed several customer pilot projects, most recently in a data center with developer STACK Infrastructure. Meanwhile, Residents Osmoses and Via Separations are developing membrane platforms to decarbonize emissions related to industrial gas and liquid separations, respectively, which are collectively responsible for 16% of the world’s carbon emissions.
Enabling Carbon Capture at Scale
Even as carbon-neutral industrial processes like the ones listed above come online, there will still be countless existing factories that spew CO₂ into the atmosphere. In the meantime, we will need to capture those emissions to make progress towards our climate goals. To that end, several Resident companies are developing technologies to capture emissions at a low cost for manufacturers and repurpose it for valuable industrial uses.
Mantel is developing the first carbon capture technology designed to operate at the extreme temperatures found inside boilers, kilns and furnaces, capturing carbon before it ever enters the atmosphere. Their modular system bolts onto factories and power plants without modifications to existing equipment, and even generates energy in the process that can be used by the factory or power plant.
Within two years of becoming a Resident, Mantel built a lab-scale carbon capture system in The Engine’s industrial space capable of capturing half a tonne of carbon per day. The milestone allowed the company to move directly to a full-scale demonstration at a pulp and paper plant in Quebec that is expected to capture 1,800 tonnes of carbon emissions annually.
Another Resident company, Helix Carbon, is developing a drop-in solution to recycle CO₂ from existing steel plants. Today, the steelmaking industry uses syngas, a mixture of carbon monoxide and hydrogen generated from fossil fuels, as a reducing agent to convert iron ore into metallic iron. Helix Carbon’s modular system utilizes CO₂-rich flue gas directly from the factory and converts it into syngas without burning fossil fuels.
Other current and former Resident companies are also developing ways to convert captured carbon into useful industrial products. Emvolon, for example, converts CO₂ emissions into carbon-negative fuels and chemicals, while Lydian and Sora Fuel are converting emissions into sustainable aviation fuel (SAF). Without SAFs, the use of fossil fuel-based aviation fuels are expected to account for 20% of global carbon emissions by 2050.
Building a Climate-Resilient Food System
Agriculture is one of the largest contributors to climate change, as well as one of the most vulnerable to its effects. Responsible for nearly a quarter of global greenhouse gas emissions, the sector drives deforestation, depletes soils, and depends heavily on synthetic chemicals that pollute air and water. At the same time, rising temperatures, shifting rainfall, and mounting pest pressures are threatening food security around the world. In the face of these dual risks, building a more climate-resilient agricultural system is both an environmental necessity and a global imperative.
Several Resident companies at The Engine are advancing solutions that reimagine agriculture as a climate asset rather than a liability. Foray, for example, is developing a cell-based biomanufacturing platform that eliminates the need to harvest entire plants to obtain valuable compounds and materials. By producing products from plant cells grown independently of the plant, Foray’s approach can help preserve biodiversity and take less from nature, creating harvest-free molecules, materials, and seed products. Their technology also enables scalable production of native seeds to support ecological restoration, a key tool for climate mitigation and adaptation.
Another Resident company, Robigo, is tackling the emissions and ecosystem damage associated with chemical-intensive farming. Today’s pesticide-heavy model contributes to soil degradation, water contamination, and biodiversity loss — while still allowing 20–40% of crops to be lost to disease. Robigo is building a microbial platform that replaces traditional pesticides with precisely engineered microbes that defend crops and restore soil health. By reducing dependence on fossil-fuel-derived chemicals and improving crop resilience in a warming climate, their platform supports both mitigation and adaptation at the field level.
These climate-forward agtech companies exemplify how Tough Tech can reduce emissions, safeguard ecosystems, and enhance resilience in one of the world’s most foundational and fragile systems.
A Call to Support Breakthrough Climate Solutions
The companies in The Engine’s Residency program are tackling some of the hardest problems in building a sustainable future. Their work requires years of rigorous development, costly infrastructure, and unwavering commitment. We’ll continue to do our part by providing infrastructure, education and access to the diverse sources of capital they need. But given the headwinds facing the climate sector, we cannot do this alone.
The scale of the climate challenge requires collaboration across investors, corporations, philanthropy, and policymakers. Together, we can accelerate the Tough Tech solutions that will define a sustainable future.