Onnu to build UK's largest pyrolysis plant

Carbon removal
Onnu to build UK's largest pyrolysis plant

Project successes


Michael Douglas

Onnu taps into growing biochar demand with UK’s largest pyrolysis plant

New biochar plant in Welshpool will generate 2,000 tonnes of biochar every year

Greentech pioneer Onnu is creating the UK’s largest biochar production facility, which will produce 2,000 tonnes of biochar and remove 4,400 tons of CO2 equivalent of atmospheric carbon every year. Onnu also announced the launch of its own biochar business – Onnu Biochar – to meet growing demand from firms that wish to exploit the proven capabilities of biochar to stimulate plant growth.

“In the last 12 months huge volumes of biochar manufactured at the site has sold at very good prices, primarily to landscaping projects and we are now seeing a huge upsurge in interest from forestry and substrate markets,” explained Giles Welch, Onnu CEO. “However, the UK’s supply of biochar simply isn’t sufficient to meet growing demand – by building the UK’s largest pyrolysis facility, Onnu is making a significant contribution to closing that gap.”

Located in Welshpool, Powys, this new plant will feature two C1000 pyrolysis units from WoodTek with a unique inline drying approach that will increase the processing capacity of the existing site by 400%. This effectively upgrades the facility of Onnu’s partner, Carbon Hill, who will continue to be heavily involved in the operation of the plant.

The plant will pyrolyse arboreal waste in the absence of oxygen to create high-grade biochar and safely remove and sequester carbon that would otherwise be released into the atmosphere. The carbon removals will continue to generate CORCs from Puro.Earth as they have done by Carbon Hill.

Promoting the UK’s biochar sector

The project will also promote the expansion of the UK’s biochar sector by conducting trials in various settings to prove its utility to clients and regulators.

“Green waste is a huge opportunity for local authorities and organic waste processors to transform low-value arboreal waste and compost oversize into a high-value carbon feedstock – and our new site will serve as a showcase for this,” added Welch. “The commercialisation of this plant will give prospective operators and funders confidence to back the model and facilitate Onnu’s overarching goal – the expansion of the carbon removal capacity that the planet so desperately needs to facilitate its transition to Net Zero.”

About Onnu

Onnu’s ambition is to facilitate the transition to a Net Zero economy by realising the potential of biomass pyrolysis to tackle the world’s toughest decarbonisation challenges. It will achieve this by creating a pyrolysis-based Greentech industry that ensures waste biomass is processed in ways that are affordable, readily available – and acceptable to the public and the regulatory authorities. In the pursuit of that ambition.

Contact Details:

Iain Halpin – Head of Communications


07739 337 087

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