UK Office (HQ)
Address
Onnu Ltd, York House, York Road, Maidenhead, SL6 1SF,
United Kingdom
Our Vision
We see biomass pyrolysis and biochar as the most accessible and scalable of all engineered carbon removal processes, thanks to its relative simplicity, and ability to support profitable business models.
To ensure this sector thrives, and can have a game-changing impact in the fight against climate change, Onnu seeks to remove barriers to scaling, both for our own business and others, to expand and grow the market.
By 2030 we will have played our part building a world where no biomass is wasted, pyrolysis routinely generates localised green energy, biochar use is widespread and biochar CDR is removing mega tonnes of CO2 from the atmosphere.
Our targets
Our CarboFlow technology delivers clean energy, while capturing carbon, manufacturing biochar and investing in local circular economies.
By 2030, we aim to have facilitated the annual delivery of:
160k tCO2e
of carbon
removed
80k t
biochar
manufactured
200 MW
of clean energy generated
across 29
operational pyrolysis sites
Our Story
Beginnings
Onnu was founded in 2022 with the clear goal of commercializing the biomass pyrolysis industry. The technology and the climate impacts were proven, but the sector was dominated by smaller-scale research and grant supported projects which were not profitable or scaling.
Onnu's full focus was on project development. We gradually grew a team of experienced engineers and sustainability consultants to advise on pyrolysis projects, helping to bring plants online.
Alongside Onnu, we launched Onnu Bioflow to cater for landscapers, commercial growers and industrial biochar needs in the UK. We soon started supplying biocarbon and black pellets to provide renewable commodities on an industrial scale.
Today
What we encountered as project developers were technology manufacturers with long lead times and machines with a 7+ year payback.
We had otherwise excellent production sites available but the slow manufacturing process and long payback time meant it wasn't a viable solution.
It was through these frustrations that we decided to focus on engineering and manufacturing our own machine, with three main aims; build a pyrolysis machine that was affordable, versatile, and had a capacity that ultimately made it a viable option for biomass pyrolysis.
We're hiring
Our locations
Cape Town
Address
21 Dreyer Street, Claremont,
Cape Town 7780,
South Africa
Phone
Malaysia Office
Address
A-29-8, Menara UOA Bangsar, Jalan Bangsar Utama 1, Bangsar 59000, Kuala Lumpur
Our Partners
We believe in the power of collaboration and knowledge sharing. We're proud to partner with the following businesses:
Latest insights
How to choose a carbon registry
Different carbon registries have differing methodologies for project developers to adhere to, with clear instructions on what type of information needs to be provided for a project to be approved and carbon credits to be issued. But which should you choose?
How to choose a carbon registry
Looking back on 2025 and ahead to 2026
In this blog we look back on a year of change at Onnu. In 2025 we launched Onnu Bioflow and unveiled our proprietary pyrolysis technology, CarboFlow. We look ahead to what 2026 may bring.
Looking back on 2025 and ahead to 2026
Onnu and ReGenEarth Announce Landmark Pyrolysis and Anaerobic Digestion Project
Partnership creates a first fully circular and self-sustaining farm-based hub for renewable heat, biochar and carbon credits.
Onnu and ReGenEarth Announce Landmark Pyrolysis and Anaerobic Digestion Project