Tierra Prieta is a Mexican-owned biochar business located in Parras, Mexico. In partnership with Star del Norte, a local pecan processing facility, we receive pecan shells year-round and convert them into biochar in our pyrolysis units, located right next to the biomass source. Our biochar, appreciated by our customers for its high quality and proven results in the field since 2023, is produced in flake form, making it easy to use with common farming equipment. Thanks to our efficient and consistent production, our biochar is in high demand and is quickly sold in the US. We have a five-year full capacity sales agreement with Wonderchar, a US-based company, ensuring a reliable delivery of carbon removal. Fully certified under the Puro.earth Biochar Methodology with first issuance in August 2025. We currently offer carbon credits from our 2,000 biochar ton-per-year facility, which will be delivered as fully certified Puro.earth CORC 100+. Our Life Cycle Analysis (LCA) has been third-party written and audited, and we are proud to be one of the first industrial-scale carbon removal facilities in Mexico. Below is more information about our project, in line with the Carbon Business Council guidelines:

Additionality

Although Tierra Prieta has a five-year agreement to sell all biochar produced at our Parras facility, and our biochar is considered "premium" by the market for its high quality and easy-to-spread flake form, revenue from physical biochar alone is not sufficient to sustain the business. Sales from carbon removal are necessary for us to become financially sustainable in the long term and keep removing carbon. Our business model considers carbon removal as an internal subsidy mechanism for physical biochar, allowing more farmers to benefit from improved soil conditions at an accessible price point. We have conducted an extensive Investment Analysis according to UNFCC guidelines to ensure compliance with the Puro.earth Biochar Methodology.

Durability

Our production process relies on decades of scientific research to ensure 100+ years of durability for carbon removal. Before issuing credits, we lab test each batch to verify that our biochar is highly resistant to biological degradation in soil. This rigorous methodology also takes into account end-use farmland soil temperature, H/C ratio below 0.3, organic carbon content over 83%, and pyrolysis temperatures range of 650C-750C to guarantee at least a 100-year durability. We fully comply with these requirements and expect our durability to greatly exceed these initial estimates.

Net-Negativity

Our third-party commissioned and audited cradle-to-grave Life Cycle Analysis calculated 150kg CO2eq emissions per ton of biochar produced, delivered, and used. Overall, considering our lab results, average soil temperature where our biochar is applied, and including a buffer, we claim a removal of 2.0 CO2eq tons for each ton of biochar, supporting each claim with evidence from our production logs, lab results, invoices, and export documents.

Verification

Carbon removal requires extensive documentation, auditing, and verification before entry in Puro's registry. Tierra Prieta's production team meticulously logs in Cula's dMRV platform every data point in temperature, biochar output, lab tests, and other relevant information to ensure compliance with the Puro.earth Biochar Methodology. Tierra Prieta has also been rated as "Low Risk" by Sylvera, the best possible grade for pre-issued carbon removal credits.

Equity and Community Engagement

Parras, a small town noted for hosting the first vineyards in the Americas and being the first location outside the US to experience electric lighting when Thomas A. Edison demonstrated his invention to the Madero family, is both beautiful and historic. Except for our founders who live in nearby Monterrey, all our employees are hired locally. With a declining manufacturing sector and seasonal tourism and agriculture jobs, Parras faces employment challenges. We offer higher wages compared to other regional manufacturing hubs, enabling locals to work year-round close to their families without compromising their personal income. We also support local contractors, electricians, plumbers, etc., and purchase equipment from local stores to reinvest our revenue into the local economy. In addition to this direct impact, our 30% owner Star del Norte is renowned for its philanthropic investments in the Parras community, such as funding school lunches, sponsoring events that boost tourism and local business income, supporting a local women's shelter, donating to Comedor Santa Maria´s pantry, and many more charitable initiatives.

Carbon Offset

Puro.earth