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Dear Friends of Greentown,

September has been all about convening ecosystems for collaborative climate action! Last week, Greentown and our startups participated in the second Houston Energy and Climate Startup Week, where dozens of events showed momentum for the energy transition.

In addition to hosting “From Local to Global: Helping Climatetech Startups Succeed Internationally with Woodside Energy and Equinor”—a pitch-and-panel event on startup growth across borders—and the ACCEL Year 3 Showcase, we collaborated with Woodside Energy and Equinor to bring Australian and Norwegian startups to Houston in a one-of-a-kind Ecosystem Exchange program. These seven startups immersed themselves in Houston’s ecosystem during a dynamic week of pitches, curated meetings, panels, and networking that provided exposure and the opportunity to form and nurture key relationships in the U.S. market.

This week, we’re at Climate Week NYC, where we’ve hosted a startup showcase featuring 12 of our members, participated in the launch of Net Zero Insights’s latest report, co-hosted an event with FischTank PR on communications strategies for startups, and led a discussion table at an urban-innovation Climate Salon!

But we’re not stopping at these two weeks—we believe innovation is a team sport, so we’re excited to announce two partnerships with Houston organizations to advance the region’s support for climatetech and energy startups (more details below).

We’re also gearing up for the Climatetech Summit—our largest event of the year that brings together entrepreneurs, corporate leaders, investors, policymakers, philanthropists, and others to catalyze climate solutions. We hope to see you there; register for the Houston and Boston events before prices increase on Oct. 1!

Warmly,
The Greentown Team

Meet Our Newest Members

Fourteen climatetech startups joined our community in Q3 2025, working on technologies ranging from redox-loop batteries to crop-growth-prediction software. Check out the full list here, and just a sampling below!

10Dq’s redox-loop battery uses novel, water-based electrolytes to store energy in dense, low-cost, earth-abundant battery materials
Adiabatic Materials develops processes that use aqueous organic materials to produce chemicals using electricity instead of heat.
Resollant’s compact, zero-emissions hydrogen and carbon reactors provide low-cost, scalable clean hydrogen and high-purity carbon for the energy and manufacturing sectors.
HGenium develops a fully integrated water-splitting cycle that produces green hydrogen and naturally pulls CO2 from the air.

Climatetech Summit is Around the Corner

We’re just over one month away from the Climatetech Summit, happening Nov. 4 in Houston and Nov. 6 in Boston! Join us, our fantastic startups, and dozens of speakers for a day of hands-on exploration of climatetech solutions—including:

A dive into how the shale revolution can serve as a roadmap for the energy transition
Dozens of startup pitches
A live Open Circuit podcast recording
A book launch for Disciplined Entrepreneurship for Climate and Energy Ventures
Startup showcases
And more!

Two New Houston Ecosystem Partnerships

Greentown and Energytech Nexus are working together to enhance founders’ access to investors and capital! Energytech Nexus will move into Greentown Houston and open a designated investor lounge, which will host regular fundraising meetups and investor office hours.

It will also launch a new AI-driven investor platform, Cephyron IRM, to better connect early-stage technologies to sources of capital; Greentown members will gain early access to the platform. Learn more.

Greentown and Nominal, developer of a software stack that enables hardware teams to test and iterate rapidly, are launching an Industrial Center of Excellence within Greentown’s Houston incubator.

The two organizations will co-develop and host specialized workshops, and Nominal will hold weekly office hours for Greentown startups, offering free consultations on how to build the right test infrastructure, why testing is paramount, and how to move from prototype to scaled deployment—as fast as possible. Learn more.

Startup News

What does climate action look like? Climatetech startups receiving funding, winning awards, deploying their tech around the world, and more! Read a roundup of our startups’ recent milestones here and check out some highlights below:

Hertha Metals raised $17M to scale its energy-efficient and cost-effective green-steelmaking process.
Haffner Energy signed a long-term sustainable aviation fuel offtake deal with Luxaviation.
Spare-it partnered with Capgemini to bring its real-time waste intelligence platform to Capgemini’s global enterprises.
Ambient Fuels was acquired by Electric Hydrogen and entered a strategic relationship with Generate Capital to accelerate innovative hydrogen project finance solutions worldwide.
Cemvita expanded its footprint in Brazil with a strategic technology acquisition that strengthened its portfolio of carbon-negative industrial biotechnologies and added a new senior hire to drive regional growth.

More Upcoming Events

Sept. 30: Pay it Forward: Financial Pathways to Project Success & Smart Building Opportunities Summit [Greentown Boston]
Join our member Beacon Climate for this event focused on bringing together developers, owners, financiers, and solution providers for a dual-sided conversation on how to make buildings smarter, more cost-effective, and climate-aligned.

Oct. 28-30: VERGE at Trellis Impact 25 [Ecosystem Event - San Jose, CA]
We’re a Startup Pavilion partner at VERGE—the premier event for professionals decarbonizing their organizations and supply chains. As part of Trellis Impact 25, you’ll also gain access to GreenFin and Bloom. Use Greentown’s partner code TI25GTL for 20 percent off.

Oct. 31: Climatetech Founders Networking Breakfast [Greentown Boston]
Wrap up Tough Tech Week with a networking event for climatetech entrepreneurs, subject-matter experts, former founders, and other industry leaders interested in sharing their expertise.

Nov. 3-7: SOSV Climate Tech Summit [Ecosystem Event - Virtual]
Hear from leading climatetech investors, founders, and technologists at the Fifth Annual SOSV Climate Tech Summit (free and virtual). The summit will explore the breakthroughs, challenges, and future of the climatetech ecosystem. Check out the confirmed lineup of speakers and register here!

Out Now: The U.S. Clean Energy & Industrial Innovation Report

Our friends Net Zero Insights just released the U.S. Clean Energy & Industrial Innovation Report, which explores how shifting political priorities and turbulent markets are reshaping the investment landscape.

Greentown was proud to partner on this report, with our team and startups participating in focus groups! Read the report here.

External Newsletter — September 2025

From The Ecosystem

External Newsletter — September 2025