The four-week initiative combines expert-led workshops, mentoring, and leadership panels, with some participants also gaining the chance to trial their solutions within Amazon’s European operations.

The new cohort is selected from more than 550 applicants and targets three key environmental challenges: energy efficiency, waste reduction, and water management. Among the chosen companies is Cartesian, a Norwegian technology firm that has created a thermal battery designed to change how buildings store and consume energy.

Cartesian’s CTO, Alexis Sevault, comments: “Being chosen is a powerful validation of our solution and that our mission matters. We are excited to take this next step toward scaling our impact."

Other participants include developers of ultra-thin, flexible solar panels, an air conditioning system capable of cutting energy use by up to 90%, and a company that uses an ‘artificial stomach’ to convert food waste into biogas and hydrogen for energy production.

Olivier Pellegrini, European Director of Sustainability & Packaging Operations at Amazon, says: "What stands out about this cohort is their combination of technological innovation and practical applicability. These founders are developing technologies that have real potential for implementation within our operations and could be truly transformative at scale. Their approach connects well with Amazon's own culture of innovation and sustainability goals."

Amazon points to the potential for real-world adoption, highlighting that it invested €750,000 across five pilots from last year’s programme. The most successful technologies may be integrated into its European operations.

Launched in 2022, the Amazon Sustainability Accelerator initially focused on sustainable consumer products before broadening into climate technology. With the addition of this cohort, more than 70 companies have now been supported across six groups.

The programme runs in partnership with Founders Intelligence, part of Accenture. Livia Solustri, Strategy Lead at Founders Intelligence, adds: "We're excited to continue our collaboration with Amazon's Sustainability Accelerator for the 2025 Climate Tech Challenge. Last year's programme demonstrated the impact of connecting innovative startups and scaleups with Amazon's operational expertise. We're proud to play a role in identifying and supporting companies that can drive meaningful environmental change while delivering operational efficiency at scale."

The companies joining the second edition of the ClimateTech cohort of the Amazon Sustainability Accelerator are:

Mhor Energy (UK)

Mhor Energy has developed a flow battery that stores energy in liquid form, operating like a rechargeable battery but on a much larger scale. Designed with a projected lifespan of 20 to 25 years, the system performs efficiently even in high temperatures without the need for cooling. Its durability and reliability make it particularly suitable for solar-powered facilities that require a continuous energy supply.

Cartesian (Norway)

Cartesian, a Norwegian technology company, has created a thermal battery that stores heat or cold in phase-changing materials, similar to how ice turns into water. The system captures energy when it is cheap and abundant, then releases it during peak demand, helping to ease pressure on the power grid.

Over Easy Solar (Norway)

Over Easy Solar has designed a lightweight, vertical solar system that differs from conventional flat installations. Its prefabricated units weigh only 11kg per square metre, around half the weight of standard panels, enabling solar deployment on buildings that could not previously support traditional systems.

Active Surfaces (US)

Active Surfaces has developed ultra-thin, flexible solar sheets made with perovskite, a material that requires ten times less material than conventional panels while offering similar efficiency. The sheets can be installed with adhesive, helping to cut installation time.

Omniflow (Portugal)

Omniflow, based in Portugal, has developed streetlights powered by a combination of wind and solar energy that consume 90% less energy than conventional models. The units integrate motion sensors to dim lighting when no activity is detected and can also support smart city applications such as air quality monitoring, EV charging, and 5G connectivity.

Blue Frontier (US)

Blue Frontier has developed air conditioners that use liquid desiccant technology to control temperature and humidity separately, unlike conventional systems that manage both in a single process. The approach can cut energy consumption by up to 90% and incorporates thermal energy storage, enabling operation for four to six hours without drawing power from the grid.

Shayp (Belgium)

Shayp provides a monitoring system that tracks the ‘pulse’ of pipelines to detect hidden water leaks. Connected to existing meters and powered by artificial intelligence, the technology has already saved over 21 billion litres of water and typically cuts building consumption by up to 20%.

Solaq (Netherlands)

Solaq, a Dutch startup, has developed a system that extracts drinking water from atmospheric moisture using a specialised absorption process. Housed in standard shipping containers for straightforward deployment, the units can produce up to 5,000 litres of clean water per day without the use of harmful chemicals.

NANDO (Italy)

NANDO converts standard waste bins into intelligent monitoring stations. Small bins are tracked via an app, larger containers with sensors, and AI-powered cameras analyse waste in real time. The system recognises more than 70 waste types, enabling facility managers to quickly identify incorrect sorting and contamination.

Greyparrot (UK)

Greyparrot has created computer vision systems that monitor waste on conveyor belts, identifying and categorising materials in real time. Its AI recognises more than 110 waste types, ranging from standard recyclables to complex composites.

Vuala (UK)

Vuala has developed a bio-mechanical ‘artificial stomach’ that uses specialised microorganisms to process mixed food waste on site. The system converts waste into an odourless material that can be stored for up to a month before being used as a feedstock for biogas and hydrogen production, transforming disposal into a renewable energy resource.

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