Enhanced Rock Weathering (ERW) is quickly gaining traction as a promising carbon sequestration solution in the battle against climate change and reducing carbon dioxide (CO2) emissions. This innovative method involves spreading silicate minerals on croplands to gradually sequester CO2 in the form of carbonates. With the involvement of various monitoring, reporting, and verification (MRV) companies and an increasing number of field trials, ERW is emerging as a potential game-changer in the fight against global warming.
Researchers from the University of Guelph, including Dr. Rafael Santos and Dr. Emily Chiang from the School of Engineering, have significantly contributed to the development of ERW through their Food from Thought-funded project. They have pioneered a field-trialed MRV approach using calcimetry, a scientific method for measuring the amount of calcium in a substance. This method allowed them to track the increase of inorganic carbon in agricultural soils using the ERW process.
“Our research involved collecting soil samples from different depths in a farm treated with a mineral called “wollastonite.” By analyzing these samples in the laboratory, we discovered that the soils treated with the mineral had five times more inorganic carbon than untreated soils,” said Dr. Santos.
He further explained that the pH level of the treated soils increased by up to 1 unit, indicating that the mineral was effectively dissolving in the soil.
The researchers also conducted various tests on the soil samples, including analyzing the minerals and structure, which confirmed that adding the mineral increased the amount of inorganic carbon in the soil.
ERW carbon sequestration in croplands becoming a commercial and global reality
Dr. Santos shared his insights on ERW in a 2022 interview with OpenAir’s CDR Horizons show, significantly boosting the visibility of the ERW work conducted at the University of Guelph.
Building on this momentum, Everest Carbon, a leading MRV company, took the University of Guelph’s ERW approach to the commercial level. Their efforts were rewarded with the largest contract to date for wollastonite amendment for ERW in India. This partnership highlights industry players’ growing interest and commitment to the large-scale implementation of ERW as a viable carbon sequestration solution.
The commercialization of ERW has attracted several MRV companies worldwide, leading to a surge of ERW field trials. The collective goal is to scale up ERW to achieve gigatonne/year CO2 removal capacity in the foreseeable future, reflecting the increasing faith in ERW’s potential to contribute significantly to global CO2 emissions reduction efforts.
ERW carbon sequestration is helping to address agricultural challenges
The environmental implications of ERW are substantial, as this approach mitigates climate change by drawing down CO2 and enhancing soil fertility. The sequestered carbonates enrich the soil, improving agricultural yields and potentially reducing the need for chemical fertilizers. ERW represents a unique opportunity to simultaneously address climate change and food security challenges.
As ERW continues to gain traction and evolve into a mature carbon sequestration method, it holds immense promise in the global fight against climate change. Ongoing research, commercialization efforts, and support from MRV companies are driving this innovative approach toward significantly reducing CO2 emissions and transitioning to a more sustainable future.
“Enhanced Rock Weathering has the potential to revolutionize carbon sequestration efforts and make a significant impact on mitigating climate change,” said Dr. Santos.
“Our findings underscore ERW’s feasibility and environmental benefits, paving the way for a more sustainable and resilient agriculture sector.”
This research is funded in part by the Ontario Agri-Food Innovation Alliance, a collaboration between the Government of Ontario and the University of Guelph.