Climate technology founders building solutions capable of creating significant environmental impact can apply for the Carbon13 Venture Accelerator, an intensive programme designed for early-stage software and deep-tech startups.

The current cohort is particularly relevant to founders developing solutions around climate change, decarbonisation, water, biodiversity, adaptation, resilience and other challenges affecting the planet’s life-support systems.

Successful startups can receive the opportunity to pitch Carbon13 for €150,000 to €250,000 in pre-seed investment.

The current programme page lists September 30, 2026 as the final application date, with the next cohort scheduled to begin during the week of November 16, 2026. Applications are assessed on a rolling basis.

What Is the Carbon13 Venture Accelerator?

Carbon13 is a European climate-focused venture builder and investor.

Since 2021, it has worked with and invested in more than 100 climate technology startups across areas such as energy, agriculture, construction, manufacturing, transportation and emerging climate technologies.

The Venture Accelerator is designed for founders who already have a company and need focused support to strengthen product-market fit, go-to-market strategy, fundraising readiness and environmental impact.

Carbon13 describes the programme as a “superadvisor” rather than a conventional classroom accelerator.

The emphasis is on working directly with founders to solve company-specific problems.

Who Can Apply?

The programme targets founding teams building early-stage software or deep-tech and science-based companies.

To meet the main eligibility criteria, the startup should:

• Have at least two founders;
• Be incorporated in the United Kingdom or European Union;
• Expect to raise approximately €1 million to €3 million within the next 12 to 18 months;
• Ideally be around Technology Readiness Level 6 to 7;
• Have raised little or no institutional equity funding;
• Be capable of creating substantial climate or environmental impact.

Carbon13 is looking for businesses with the potential to create impact at global scale.

Its broader ambition is for each venture it backs to develop towards the potential to reduce or remove the equivalent of approximately 10 million tonnes of CO2e annually at scale.

Founders do not need to have completely solved the impact calculation before applying, but they should understand why the technology could eventually operate at significant scale.

Software Startups Need More Than an Idea

Software companies are expected to arrive with more development than founders entering Carbon13’s Venture Builder programme.

The Venture Accelerator says software businesses should generally have:

• At least an MVP;
• Strong understanding of the industry;
• A clearly defined customer problem;
• Evidence of traction;
• Good founder-problem fit.

AI, data science, machine learning and other software technologies can qualify when they are genuinely solving environmental or climate challenges.

Carbon13 also states that its expectations for software businesses have risen with the development of AI. Teams should demonstrate an ability to build and execute rapidly rather than simply adding an AI label to an ordinary business.

What About Deep-Tech Startups?

Deep-tech and science-based companies receive a different form of support.

These businesses might be developing technologies involving advanced materials, chemistry, engineering, biotechnology, energy systems or physical infrastructure.

Carbon13 generally prefers technologies around TRL 6 or 7, although ventures around TRL 5 or 8 may still be considered.

The team should have credible technical expertise.

For science-based companies, Carbon13 says one founder would often have a PhD or equivalent experience, while another founder should demonstrate strong commercial capability.

The programme helps these ventures think through challenges such as intellectual property, pricing, product-development timelines and commercialisation.

How Does the Programme Work?

The current Venture Accelerator has two main phases.

Phase 1: Eight-Week Sprint

The first phase runs for approximately eight weeks and is delivered remotely.

Founders work directly with Entrepreneurs in Residence and other specialists on areas such as:

• Go-to-market strategy;
• Product and technology roadmap;
• Commercial traction;
• Investment readiness;
• Team development;
• Climate impact;
• Fundraising strategy.

Companies participating in Phase 1 provide Carbon13 with 1% in options in recognition of the advisory support provided during the accelerator.

At the end of the phase, selected startups pitch to Carbon13’s investment committee.

How Much Does Carbon13 Invest?

Companies selected by the investment committee can receive between €150,000 and €250,000 in pre-seed investment.

The investment is made through a SAFE and is structured to target approximately 4% to 7% ownership, according to the current programme page.

This is important: the money is not a grant.

Carbon13 becomes an investor in companies it selects.

Founders should therefore assess the investment terms, expected dilution and the 1% programme options with appropriate professional advice.

What Happens After Investment?

Startups receiving investment move into the second stage, a 12-month Growth Phase.

The goal is to help the company raise approximately €1 million to €3 million in additional funding within the following year.

Support remains highly personalised and can include investor introductions, fundraising strategy, commercial milestones and access to Carbon13’s climate-tech network.

Invested companies can also pitch at Carbon13’s Climate Innovation Showcase before invited investors and partners.

How Are Startups Selected?

The application begins with a written submission and a two-minute founder video.

Promising applicants proceed to interviews with the Carbon13 team.

Successful finalists also undergo due diligence before receiving a formal offer.

Applicants should therefore be ready to discuss both technical and commercial aspects of the business.

A strong application should explain:

• The environmental problem;
• The technology;
• Current development stage;
• Customer problem;
• Existing traction;
• Founding team;
• Market size;
• Potential environmental impact;
• Fundraising plans;
• Why Carbon13 can materially improve the company.

Current Application Deadline

Carbon13’s current Venture Accelerator page lists September 30, 2026 as the final deadline.

Because that date has now arrived and the page does not specify a public closing hour, founders interested in this cohort should check the live application immediately rather than assuming submissions remain open until midnight.

The next cohort is scheduled to begin during the week of November 16.

Apply to the Carbon13 Venture Accelerator

For climate founders who already have an early product and are preparing for their first major institutional financing, Carbon13 offers something more substantial than general startup mentoring: specialised climate expertise, intensive company-building support and a direct pathway to potential pre-seed investment.