Silicon Valley-based climate technology startup CarbonZero.Eco has announced the completion of its first biochar production plant in Colusa County, California. The company has also entered into a commercial agreement with carbon-removal firm Climeworks for the purchase of CarbonZero.Eco’s carbon-removal credits.
Climeworks has a diversified portfolio of durable carbon-removal solutions designed for companies seeking to reach net zero, reduce climate-related risks, and support long-term climate impact. CarbonZero.Eco aims to mainstream biochar use in farming and address supply shortages, benefiting farmland while helping minimise carbon emissions.
The Colusa County plant is the company’s first large scale production facility. The processed biochar will be blended into compost used directly by partnering farms, enriching soils for future almond crop cycles. The company states that its close proximity to almond shell stockpiles will eliminate the need for feedstock transport, reducing operational emissions. It aims to develop the facility into a hub for carbon negative agriculture that is both practical and economically viable.
By placing our first plant directly where agricultural waste is generated, we’re creating a closed-loop system that benefits farmers, the environment, and the climate. Our mission is to empower American farmers to enhance soil health, improve crop yields, and unlock new revenue streams—while removing atmospheric CO₂ at scale through next-generation biochar production.
CarbonZero.Eco, founded in 2024 by Harper Moss, raised about $3.5 million in early 2025 from investors including Google, Meta and Amazon. Since then the company has been able to secure agreements with more than hundreds of almond farms across Colusa and Yolo Counties in California’s Sacremento valley. The company says these partnerships could enable the mitigation of up to 1.5 million tons of CO₂ from agricultural waste that would otherwise decompose and release carbon into the atmosphere.
Almond Shells to Long Term Carbon
According to estimates referenced in UN Food and Agriculture Organization (FAO) analyses, global agricultural waste generation exceeds 1.5 billion tonnes annually. Intergovernmental Panel on Climate Change (IPCC) assessments indicate that traditional disposal methods such as landfilling and open burning contribute around 3% of global greenhouse gas emissions.
To help address this issue, biochar remains a viable alternative that converts biomass into a stable form of carbon, preventing CO₂ from being released during decomposition and storing it for thousands of years. It can improve soil structure, enhance fertility, and support long-term gains in crop productivity while enabling the creation of high value carbon removal credits.
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According to CarbonZero.Eco, roughly half a million tons of shell material is currently burned or left to decompose in California’s Central Valley. The region also faces ongoing groundwater stress, with hundreds of aquifers being depleted each year. Parts of the Central Valley have sunk so much over the past century, and some areas continue to experience subsidence of up to a foot per year.
The company says its biochar can help reduce on-farm water needs. According to the company, biochar amended soils retain about 20% more water, a level it identifies as important for slowing the depletion of local reservoirs. The company is working with almond growers to convert up to 1.5 million tons of almond shells which typically decompose over two years into biochar for long term carbon storage and agricultural benefit.
Collaborating for Climate Impact
The partnership between CarbonZero.Eco and Climeworks reflects a broader shift in climate technology, where carbon-removal companies increasingly rely on collaborative models rather than operating in isolation. For CarbonZero.Eco, working with an established carbon removal provider offers access to verified methodologies, market credibility, and buyers already familiar with carbon credits. Climeworks, in turn, gains a pipeline of nature based or waste derived carbon removal supply that complements its engineered solutions, allowing it to diversify beyond direct air capture.
Operationally, the partnership enables CarbonZero.Eco to link its biochar production with a recognised verification pathway, a key step for any early stage company trying to enter the carbon credit market. It also helps ensure that the environmental claims tied to biochar projects meet emerging standards for durability, traceability, and monitoring.
As demand for high quality carbon removal grows, these kinds of cross-sector collaborations are becoming increasingly important for bridging technological development with market adoption.