We track the progress of a carbon removal project through our certification framework. This roadmap moves from a preliminary assessment of eligibility toward full certification under the Puro Standard.
The facility has successfully completed the preliminary assessment conducted by the Puro team, meeting the minimum criteria for listing as a future supplier on Puro.earth.
The facility has passed the third-party facility audit, verifying compliance with the methodology, as well as output audit, verifying the net volume of removed carbon. The facility has been issued CORCs and continues its removal operations, as well as monitoring and reporting to Puro.earth.
Development status
We monitor a facility’s maturity as it moves toward industrial-scale operations. This status identifies whether a project is in development, under construction, or actively removing carbon from the atmosphere.
The feasibility study is ongoing. The Supplier is still collecting data to prove the concept.
The front-end engineering and design are ready and methodology compliant. There is a clear plan to monitor and measure. The LCA is up to the needed quality level or subject to small improvements. The technology has been used before. There are commercial agreements with the relevant business partners of the facility.
The facility is fully funded and is being implemented. Relevant infrastructure is being built.
The facility is operating as a carbon removal facility.
information
More about Dark Earth – ARS facility
Sentinel Earth AG is a Swiss carbon markets company that develops carbon removal and insetting projects and trades environmental assets across the voluntary, Article 6 and compliance markets. Dark Earth is Sentinel Earth's carbon removal project at the Asia Renew Science Biochar Production Facility in Lim Chu Kang, in the north-west of Singapore. Built and run by Asia Renew Science, the facility turns local organic waste into biochar, a stable, carbon-rich material that permanently locks away carbon and improves soil quality. Once fully operational it is expected to remove an estimated 9,400 tonnes of CO2 each year.
The facility uses a custom-built pyrolysis system that runs on three locally sourced feedstocks: chicken manure from the host farm, industrial waste wood chips, and urban green waste. Left to decompose or be burned, these feedstocks would release methane and nitrous oxide. Instead, they are heated under oxygen-limited conditions and the carbon is locked into biochar, with the plant processing around 60 tonnes a day each of chicken manure and wood chips. The biochar then goes to a fertiliser producer for soil amendment in Malaysia and a landscaping company for vertical greenery, parks, roadside greenery and related horticulture purpose in Singapore, where it improves soil structure, water retention and nutrient availability. Every removal is tracked by independent MRV provider, giving buyers a continuous, auditable record of production and use.
The project also addresses a pressing local problem. Singapore has very limited land for waste disposal and relies heavily on incineration, so diverting organic waste into a long-lived, productive material directly supports the country's Zero Waste Masterplan and Green Plan 2030. By taking manure from a co-located farm and turning recycled wood and green waste into a soil product, the facility closes a local loop from city waste to city greenery. It also creates employment and contributes to SDG Target 11.6 (Sustainable Cities and Communities).
As Singapore's first urban biochar carbon removal facility, Dark Earth is a model for how dense, land-constrained cities can turn an everyday waste problem into durable, verifiable carbon removal.
Waste management: At full capacity the facility treats around 39,600 tonnes of waste a year, roughly half poultry manure and half waste wood and urban green waste, keeping it out of landfill, incineration or composting.
Circular economy: The facility turns Singapore's own waste, farm manure, waste wood and city green waste, into biochar that goes back into local soils, building a closed loop in one of the world's most land-constrained cities.
Renewable energy: The pyrolysis process generates thermal energy that is recovered to sustain the reactions and dry incoming feedstock, reducing the facility's reliance on external power.
Healthier soils: Applied to farmland through an organic fertiliser blend, or used in the city's vertical green walls, rooftop greenery and parks, the biochar improves soil structure, water retention and nutrient availability.
Air pollution reduction: By diverting waste from decomposition or incineration, the project avoids the methane, nitrous oxide and particulates those routes release, and the facility's own emissions are filtered to meet local air-quality limits.
Green jobs: The facility supports year-round local employment in production, operations and monitoring.
Community engagement: The project was developed with local consultation, including public meeting, on-site air-quality monitors and reduced night-time operations in response to residents' feedback.
sdgs
Sustainable development goals
Only listed sustainable development goals (SDGs) have been assessed according to the Puro standard SDG Assessment Requirements and validated and verified by a VVB.
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