Defining success

At Cleantech Open Northeast, we measure our impact by the success of the startups we accelerate. Since 2005, we've accelerated 642 cleantech companies. 62% are still active or have achieved a successful exit. These numbers and the following profiles demonstrate our pivotal role in advancing the green economy.

The program has accelerated 642 startups. 62% are still active or have been acquired.

Key metrics

The primary metrics of startup success that are available to us include revenue generated, people employed, and funds raised. In addition, we can report on the number of patents, the diversity of the founders in our cohorts (through self-reporting by the startups), and successful exits.

For the most current report, we spent some time determining which startups are still active. In some cases, this meant contacting the founders directly to determine if the startup was still operating, if it became another entity, if it split into more than one entity, or if it closed.

Growing the Green Economy

62% of the 642 Cleantech Open Northeast alumni (from 2005 to 2024) are still in business or have had a successful exit. They have raised more than $2.02 billion, they employ more than 7,800 people in the climate economy, and in 2024 they generated more than $696 million in annual revenue. 30 have had a successful exit.

Over the last two years, the number of people employed by Cleantech Open Northeast alumni has increased 250% to 7,800.

The most awarded startups in the 2024 cohort

These companies are working with chemicals and advanced materials to solve complex climate problems.

69% of the startups in the 2024 cohort are led by a member of an underserved community. This number has continued to rise over the past few years.

These are companies to watch!

hydroGel is an MIT spinout improving industrial separations using novel polymeric resins. Their goal is to create more sustainable purification processes that reduce overall processing costs and increase product yields. Their current focus on purification of fermentation products for food and biopharmaceutical industries has led them to a promising paid proof-of-concept with a large South Korean customer for amino acid purification.

Arculus Solutions developed a hydrogen-barrier coating at MIT that enables retrofitting natural gas transmission pipelines to safely transport hydrogen. With their coating applied on the internal surface of pipelines, it is possible to transport a mix of hydrogen and natural gas or even pure hydrogen, without embrittling the steel. The team is currently advancing an autonomous robot able to travel inside natural gas pipelines while applying the coating.

Turnover Labs is a carbon utilization company building the most durable CO2 electrolyzer systems on the market today. Using proprietary technology, their process converts mixed emissions from chemicals manufacturing into basic chemical building blocks. By recycling customers' emissions back into their processes onsite, Turnover Labs' technology can utilize CO2 from hard-to-abate processes and use that as feeds for the overall facility, helping reduce CO2 footprint and increase facility capacity.

Green Spear is revolutionizing the graphite space by transforming sustainably sourced CO2 directly into graphite for the EV battery and grid storage space and dramatically increasing supply chain resilience by producing it in the USA. They work to sequester tons of CO2 and offset significantly more, all while adding significant value to the carbon chain.

Recently acquired Cleantech Open Northeast alumni companies

These companies represent different cleantech categories. Interestingly, several of them are in the solar space.

30 alumni companies have been acquired.

EnergySage - acquired by Schneider Electric - offers a shopping calculator to simplify shopping for clean home energy solutions. EnergySage is on a mission to empower people everywhere to switch to affordable, reliable clean energy solutions with trusted resources, unbiased advice, and a simple shopping experience.

NBD Nano - acquired by Henkel – We functionalize and create new molecular structures to enhance surface properties for a variety of materials. This includes making product surfaces repellent to water, oil, stains, microbials, and fingerprints. What makes their solutions unique is we tailor each product at the molecular level so that it matches the substrate, providing a high level of performance and extended durability.

QD Solar - acquired by SunDensity – is a next-generation solar materials company developing advanced multilayered solar photovoltaics with highly tuned and complementary perovskite technology to enhance solar efficiency.

Solstice – acquired by MyPower, a Mitsui Company – creates solar for every American through community solar. The customer reserves a share of panels at a nearby solar garden. The share’s production earns the customer credits on their electric bills that bring down costs.

SpaceSense – acquired by xFarm Technologies – an AI platform designed to help data scientists and developers build geospatial solutions faster, easier and at scale.

SunBug Solar -  – acquired by ReVision Energy – a full-service renewable energy provider committed to helping customers find the right solution, and being by the customer’s side every step of the way.

The most successful Cleantech Open Northeast alumni

Of all alumni, these companies are making the greatest impact in the US and around the globe. They have raised the most money, they are generating the most revenue, and/or they are employing the most people.

The most successful Cleantech Open Northeast alumni represent eight cleantech categories:  Chemicals & Advanced Materials, Energy Distribution & Storage, Energy Efficiency, Energy Generation, Green Building, Transportation, Waste, and Water.

Bevi - A bubbly, bottleless office water dispenser for any commercial space. Bevi water coolers eliminate bottled water delivery costs and reduce plastic waste.

BlocPower - Transforming America's buildings into climate solutions.

Through expert construction management, inclusive financing, and unwavering commitment to communities, they’re proving that energy-efficient upgrades aren't just good for the planet—they're good for business.

Cambrian - A leader in sustainable resource management, providing clean water, renewable energy, and water treatment as a service. Wastewater is transformed into clean water and clean energy.

Divert - An impact technology company on a mission to Protect the Value of Food™. They create sustainable infrastructure to eliminate wasted food.

Ecolectro - Ecolectro's membrane technology unleashes the green hydrogen revolution with a stable and low-cost alkaline exchange materials process. Ecolectro makes green hydrogen affordable, efficient, and PFAS-free.

Husk is one of the world’s leading distributed utilities. Founded in 2008, the company provides reliable power to rural communities and businesses, entirely from renewable energy sources – 24 hours a day, 7 days a week – at a price they can afford. It offers customers a flexible “pay-as-you-go” energy service, using a mobile-enabled smart metering system. It provides low-cost energy that matches the growing needs of our customers; for households, community services and productive uses. Its grid-compatible solution can be rolled out quickly and cost-effectively to support national electrification plans.

Princeton NuEnergy Inc. (PNE) is an innovative U.S.-based clean-tech company, spun out from Princeton University in 2019, and reaching commercial production in 2023. The company is revolutionizing the material supply chain with our patented low-cost process for producing high-quality cathode active materials from spent lithium-ion batteries.

They recycle lithium-ion batteries from electric vehicles, consumer electronics, energy storage batteries, and manufacturing scrap. Their primary product:  directly re-usable Cathode and Anode materials at 99.99% purity – produced at half the cost of virgin material production with zero waste!

Natel Energy is a technology and engineering company working to support healthy rivers, promote biodiversity, and decarbonize the grid through hydropower that is safe for fish. Natel delivers high-performance fish-safe turbine and plant designs and engineering services informed by industry-leading CFD modeling and analysis as well as an in-house hydraulic test lab.

The Sanergy Collaborative is an alliance of organizations that harness a circular economy approach to empower cities to build carbon-negative systems that offer safe sanitation. They also work to build regenerative food systems through the production of feeds, fertilizers, and fuels from upcycled sanitation and other residual organic waste.

Sealed is a climate tech company on a mission to stop home energy waste by enabling contractors to install more home weatherization and electrification projects and grow their businesses.

SparkCharge - Powering Your Business With Mobile EV Charging Solutions. Their EV charging solutions help businesses electrify with quick, convenient, and scalable access to infrastructure. SparkCharge is the first company to create a mobile EV charging system and network, single-handedly creating Mobile-Charging-as-a-Service (M-CaaS).

ADDITIONAL INFORMATION

Data for this report includes feedback collected from the startups and others involved in the program, as well as information from Crunchbase. Although our alumni are private companies, we can track their progress with online tools like Pitchbook and Crunchbase. While imperfect, these tools give us a sense of companies’ relative strengths.

To learn more about Cleantech Open Northeast, ACT and how you can be part of our cleantech innovation community, please contact bzonis [at] cleantechopen.org.

Graphic by Manhattan Strategies.