15 new start-ups join Clean Cities Spain ClimAccelerator

• The Clean Cities programme will have supported 100 start-ups since 2021.
• With this 5th edition launched, start-ups from more than 20 countries will have participated in the accelerator.
• The new cohort shows maturity level is key, representing high technological readiness levels by products completed and tested.

Madrid, May 2025 – The Clean Cities Spain ClimAccelerator has officially launched the fifth edition of the programme. It is led by the Universidad Politécnica de Madrid, a key academic institution in technology, research and internationalization, together with the support from Climate KIC. Fifteen start-ups will be given the opportunity to connect with key stakeholders from the sustainable, investment and business ecosystem, boost their visibility at key entrepreneurial events and access top investors from all over Europe.

With a total of 100 start-ups supported over these previous editions, Clean Cities Spain ClimAccelerator stands out as a success story in the European start-up ecosystem. 

Ready, set, go!

A jury composed of investors, public and private institutions developed a thorough evaluation for the selection process. Nearly one hundred applicants were assessed according to their business model, product, impact, and investment readiness, among other criteria.

However, only the top 20 per cent made the cut to accelerate their solutions that address the effects of climate change in urban areas. The kickoff marks the beginning of a nine-month journey. During this first stage, start-ups will have the opportunity to participate in 1-to-1 meetings, speed networking activities, and to attend key masterclasses from experts in the fields of business, sustainability, and communication.

Meet the 2025 cohort

These start-ups demonstrated a high level of technological maturity and positive environmental impact on cities:

Amertate (Finland) presents a hybrid wind turbine which delivers reliable, affordable green energy on-site for businesses and residential buildings.

BioTwin (United Kingdom) designs and develops low-carbon construction materials. Its first innovation is a hemp-based wall stud to replace steel ones in partition walls.

Circular Carbon (Poland/Spain) decarbonises urban infrastructure through industrial waste recycling and CO₂ sequestration.

Cooling Photonics (Spain) offers passive cooling solutions that reduce energy consumption, zero carbon emissions, increase system performance, and lower operating costs.

Cosmotaics (Austria) transforms solar farms into water-positive ecosystems by preventing panel soiling and harvesting dew.

Grasshopper Air Mobility (Spain) develops sustainable drones to help industrial logistics companies transport pallet cargo and enhance automation.

Joulzen (Austria) transforms discarded oil tanks into smart thermal storage systems, allowing households to store excess renewable energy as heat.

LNCC (Spain) captures, stores, and recovers CO2 through innovative solutions to help businesses (construction, waste producers, smart cities) and governments achieve climate-neutral results.

MinervaS (Italy) develops software and hardware solutions for sustainable mobility and advanced energy management, transforming scientific research into scalable technologies.

MycoFarming (The Netherlands) engineers biofilters using fungal mycelium to extract pollutants from water, cleaning it with minimal energy and CO₂ costs.

REPS (Austria) builds a mechanical energy converter that can convert lost energy from motor vehicles into clean electrical power.

Sustein Material (Spain) converts local waste into local construction products on a global scale through a replicable circular system that upcycles 70 per cent of healthcare waste.

Sylvalgae Srl (Italy) turns organic waste into high-value products with microalgae, creating sustainable biofertilizers, animal feed, biofuels, and biohydrogen for a greener future.

UrbanVind (The Netherlands) optimises urban mobility by leveraging AI-powered demand forecasting and real-time data analytics, making shared transport smarter, more efficient, and sustainable.

WERER ENERGY (Türkiye) develops lithium energy storage systems, battery-based charging stations, portable energy storage units, decentralising energy and reducing electrical infrastructure investment.

Last but not least, this programme addresses the climate challenges in urban contexts by taking a multilevel, multi actor, and systemic approach. Therefore, a variety of organisations actively support this accelerator. From the public sector: city hall of Madrid, city hall of Valencia, city hall of Segovia, Zaragoza Ciudad del Conocimiento Foundation and Center for Innovation in Circular Economy. From the private sector, corporates as Ferrovial, CREA Madrid Nuevo Norte, Amadeus Nexwave, and SMEs as Zubilabs and Vranded Haus.

About Clean Cities Spain ClimAccelerator

The Clean Cities Spain ClimAccelerator is an acceleration programme launched in 2020 with the support of the Climate KIC, with the aim of having an impact on climate change in urban areas, as well as the commercialization of clean technologies (clean tech). The programme is aimed at startups that develop solutions with special emphasis on transforming urban ecosystems so that they are climate neutral, from mobility to waste, energy or health. There are 100 startups from more than 20 different countries that are members of the Clean Cities community.

About the Universidad Politécnica de Madrid

The UPM is the 1st Spanish-speaking Technological University and the 55th Technological University in the world. This University is characterized by a strong commitment to the SDGs and is working to have a climate neutral campus by 2040. The Entrepreneurship unit aims to stimulate the innovation process in the technological ecosystem. To this end, it has created and developed an “open technological ecosystem” linked to the development of products/processes based on technologies, with 330 high-tech startups created and more than 250 million euros raised in recent years. Under this premise, the University develops activities that include training for entrepreneurs and the incubation and acceleration of startups.

For further information: https://cleancities-accelerator.com/

Contact: accelerator.climate@upm.es

Follow on LinkedIn: https://www.linkedin.com/company/clean-cities-climaccelerator/