Show Notes
Episode 26 is with Rahul Shendure, CEO of CarbonBuilt. There are many different storage pathways for carbon dioxide removed from the atmosphere. One storage medium that we don't talk about enough is storage of CO2 in long-lived products like concrete. Storing CO2 in concrete not only helps solve the CO2 storage problem - especially for smaller, modular carbon removal deployments - but helps decarbonize a very carbon intense product. My guest today, Rahul Shendure, leads a company that is developing ultra low carbon concrete that is coming off the production line today and demonstrates the exciting potential for integrating carbon removal technologies alongside other decarbonization technologies in existing industrial processes. Rahul Shendure is a serial entrepreneur and investor focused on sustainability and health. He is the CEO of CarbonBuilt, whose technology enables the production of ultra-low carbon concrete, reducing emissions by 70-100%. He previously served as Co-Founder and CEO at Bellwether Bio, whose acquisition by Guardant Health led to the launch of the first blood-based colorectal cancer screening test. Rahul’s earlier engineering and commercial roles span a wide range of climate-related industries ranging from plastics (GE), hydrogen fuel cells (Ballard Power Systems), renewable fuels and chemicals (Amyris) and next generation renewable electricity (Oscilla Power). Rahul earned a B.S. in Chemical Engineering from MIT and received his MBA from Harvard Business School. CarbonBuilt, winner of the NRG COSIA Carbon XPRIZE, enables concrete manufacturers to produce ultra-low carbon concrete products with 70-100% less embodied carbon. CarbonBuilt’s technology replaces most of the expensive, high-carbon Portland cement typically used during concrete manufacturing with a proprietary low-cost cement alternative made from widely-available low carbon materials. These materials harden after chemically reacting with CO2, to not only strengthen the blocks, but also permanently store the CO2 in solid form, diverting it from the atmosphere. Because it can be cost-effectively installed at existing concrete manufacturing plants and delivers products that meet ASTM C90 and other applicable industry standards without increasing costs, CarbonBuilt’s technology can be rapidly adopted by the nearly 800 concrete plants in the U.S. alone. In this episode, Na’im and Rahul discuss: * Concrete and its carbon footprint; * CarbonBuilt’s technology for producing ultra-low carbon concrete; * The distinction between emissions avoidance and removal both in CarbonBuilt’s technology as well as its credit system; * CarbonBuilt’s commercial partnership with Blair Block; * CarbonBuilt’s participation in the Four Corners Carbon Coalition’s first project; * Barriers to scaling low carbon concrete technology and the role of policy in addressing these barriers. Relevant Links: * CarbonBuilt * CarbonBuilt and Blair Block commercial partnership * Four Corners Carbon Coalition * CarbonBuilt and Four Corners Coalition * Paving the Way for Low-Carbon Concrete: Recommendations for a Federal Procurement Strategy * Concrete: Square one for scaling distributed direct air capture? Special note: I'm looking for someone to support the production, editing, and promotion of this podcast. I’m looking for someone who is passionate about carbon removal, who can help brainstorm guest ideas, develop thought provoking interview questions, schedule and join recordings, edit recordings, write up the show notes, and promote the episode on various channels. It's an important job and an exciting opportunity to plug into the carbon removal field. This is a fully remote contract position starting October 1st amounting to about 8 to 10 hours of work per episode. You don't need to be an expert in podcasting. I certainly wasn't when I started. Just a lot of passion, diligence, organization, and a willingness to learn. If you're interested, send an email to [email protected] with y
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This is the third episode of The Carbon Curve: Canada’s Next Industrial Play, a special miniseries about embedding carbon removal into Canadian industry. Na’im speaks with Mark Selby, Chairman and CEO of Canada Nickel; Scott MacDougall, Canada Nickel’s vice-president of carbon and energy development; and Greg Dipple, co-founder and head of science at Arca. Mark and Scott explain how carbon storage became part of the Crawford Nickel Project near Timmins, Ontario. In July 2022, a 10-kilo bucket of tailings and a lab CO2 cylinder did over one weekend what Mark says would take about a decade in a tailings facility. That test is now an engineered step in Crawford’s feasibility study, and Mark says it could store up to 1.5 million tonnes of CO2 a year. Scott covers the tax credits that could help pay for it, including the push to recognize mineral carbonation under the federal CCUS credit. Greg explains what happens in the rock, how Arca measures it, and what Arca learned at BHP’s Mount Keith mine in Western Australia, the first carbon removal deployment at an active mine. He is also clear about the limits. A mining company has to cut its own emissions first, and every mine is different. Both conversations touch mining’s oldest problem, closure. Old mines can cost taxpayers billions to clean up. If the tailings store carbon, the credits can help cover that cost. At Carbon Removal Canada, we’re testing this in Thetford Mines, Quebec, through the Quebec Surficial Mineralization Hub, launched this spring with Frontier and local partners. Na’im, Mark, Scott, and Greg discuss: * Why Crawford matters for nickel supply, and how it compares with production in Indonesia * How the clean technology manufacturing and CCUS investment tax credits fit the economics * How Crawford could store CO2 for other industries in northeastern Ontario * What happens when ultramafic rock meets CO2, and how Arca measures it * What an operating mine taught Arca that a lab couldn’t * How carbon removal revenue could help clean up legacy mine sites * Why rock-based carbon removal at scale needs a bigger mining industry Relevant Links * Canada Nickel - Website * Arca - Website * Carbon Removal Canada - Quebec Surficial Mineralization Hub * Frontier - Website About Mark Selby Mark Selby is the CEO of Canada Nickel. His team took the Crawford Nickel Project from early drilling through feasibility and permitting in under seven years. About Scott MacDougall Scott MacDougall is vice-president of carbon and energy development at Canada Nickel. He came from the Pembina Institute, and before that worked at Suncor and the Government of Alberta. About Greg Dipple Greg Dipple is a professor emeritus of geological sciences at the University of British Columbia and co-founder and head of science at Arca. His 25-year research program on how mine waste captures CO2 led to Arca. About Canada Nickel Canada Nickel is developing the Crawford Nickel Project in the Timmins Nickel District of northeastern Ontario. Crawford is designed to be one of the western world’s largest nickel sulphide operations. This summer, it became the first mining project approved under Canada’s amended Impact Assessment Act. Learn more at canadanickel.com. About Arca Arca works with ultramafic mine tailings to speed up how they capture CO2 from the air. In 2023 it launched the first carbon removal deployment at an active mine site, at BHP’s Mount Keith operation. It has since signed a ten-year deal with Microsoft for nearly 300,000 tonnes of carbon removal. Learn more at arcaclimate.com. This episode was made possible thanks to the generous support of the Consecon Foundation. This episode was created and published by Na’im Merchant. Episode production and content support provided by Daniel Kelter and Tank Chen. Na’im Merchant is the co-founder and Executive Director of Carbon Removal Canada, a policy initiative focused on scaling carbon removal in Canada. He is on the advisory board of the Carbon Removal Sta
This is the second episode of The Carbon Curve: Canada’s Next Industrial Play, a special miniseries about embedding carbon removal into Canadian industry. This is the second episode of The Carbon Curve: Canada’s Next Industrial Play, a special miniseries about embedding carbon removal into Canadian industry. Na’im speaks with Bill Adams, chief sustainability officer at Mercer International; Sheila Harrison, vice-president of policy at the Alberta Forest Products Association; and Tina Rasmussen, chief business officer of MLTC Industrial Investments at the Meadow Lake Tribal Council. Bill walks through what decarbonization looks like inside a pulp company that has to make the capital case, including Mercer’s BECCS work with Svante at the Peace River mill in Alberta, which would capture about 500,000 tonnes of biogenic CO2 a year if it reaches a final investment decision. Since the interview, Emissions Reduction Alberta has approved a $7 million grant to Svante for the front-end engineering study that Bill described as the expensive step before that decision. Sheila focuses on the sector under pressure: softwood lumber tariffs, wildfire, fibre security, and the climate-competitiveness framing governments are pushing while companies are trying to keep the lights on. Her throughline is blunt. You cannot build a forest bioeconomy, or bolt BECCS onto it, if you lose the primary mills that already harvest, saw, and pulp the wood. Tina shows what it looks like when that idea is built and owned by the people whose land it sits on. At Meadow Lake, the Tribal Council’s NorSask sawmill feeds the MLTC Bioenergy Centre, and that site is becoming North Star, Canada’s first major Indigenous-owned BECCS project, with a 15-year Microsoft offtake for 626,000 tonnes of durable carbon removal. Na’im, Bill, Sheila, and Tina discuss: * What a pulp mill actually is, and why biogenic CO2 from a recovery boiler is a practical capture target * What has to be true for BECCS to move from an interesting concept to a real capital conversation at Peace River * Why Alberta’s geology, policy, and carbon-price recycling through Emissions Reduction Alberta matter for projects like this * What AFPA members are facing from tariffs, wildfire, and investor confidence * Why keeping primary forest manufacturing is the precondition for BECCS, biochar, or any forest bioeconomy * What Canadian governments need to get right for companies to be both economically and climate competitive * How North Star connects a sawmill, a bioenergy centre, and permanent underground storage * What a Microsoft-scale offtake means for an Indigenous-led project before steel is in the ground * Why majority Indigenous ownership changes how the project gets built and who benefits Relevant Links: * Mercer International - Website * Alberta Forest Products Association - Website * Meadow Lake Tribal Council - Website * Svante - Website * Emissions Reduction Alberta — Integrated FEED Study for BECCS at Mercer Peace River - Project page * ERA media release on the $20 million rural and northern package - Media release About Bill Adams: Bill Adams is chief sustainability officer and senior vice president, Canadian pulp operations, at Mercer International, a global forest products company with mills in Canada, the US, and Germany. He has spent three decades in forest products across Weyerhaeuser, Domtar, Canfor, and Mercer. At Peace River, Mercer is advancing a BECCS project with Svante that would capture about 500,000 tonnes of biogenic CO2 a year from the mill’s recovery boiler. About Sheila Harrison: Sheila Harrison is vice-president of policy at the Alberta Forest Products Association, which represents Alberta’s forest products producers across lumber, pulp, paper, pellets, and panel products. She works the files that keep the sector viable: fibre security, wildfire, energy costs, regulatory certainty, and the climate-competitiveness agenda. About Tina Rasmussen: Tina Rasmussen is chief business offi
This is the first episode of The Carbon Curve: Canada’s Next Industrial Play, a special miniseries about embedding carbon removal into Canadian industry. Na’im speaks with Jim Mann, founder and CEO of UNDO, and Brodie Berrigan, senior director of government relations and farm policy at the Canadian Federation of Agriculture. Jim explains enhanced rock weathering: finely crushed silicate rock is spread on farmland, where it pulls CO2 from the air and locks it away while feeding the soil. UNDO uses equipment farms already have and typically picks up the cost instead of sharing carbon revenue with the farmer. The farmer gets the material and whatever the field gives back. Brodie focuses on adoption. Farmers are business owners first. A new practice only scales if it works as a farm business, if neighbours can see it working, and if the policy around it feels safe enough to last. Na’im, Jim, and Brodie discuss: * What enhanced rock weathering is and why its permanence is measured in geologic time * How UNDO works on a farm: existing spreaders, no new plant, and UNDO organizing the haul and application * Why Canada, and especially the Prairies: feedstock, agriculture at scale, rail, and Farm Credit Canada as an agricultural lender * What a Microsoft-scale buyer does for the category, and why Jim wants agriculture treated as part of the solution * Who the CFA represents in Ottawa, and what the sector is facing from input costs, trade risk, and weather * The first question farmers ask when a new practice arrives * What would make an incentive last, and Brodie’s three-legged stool: environmental, economic, and social Relevant Links: * UNDO - Website * Canadian Federation of Agriculture - Website * Farm Credit Canada - Website About Jim Mann: Jim Mann is the founder and CEO of UNDO, one of the largest enhanced rock weathering companies in the world. UNDO spreads crushed silicate rock on farmland to permanently store CO2 and return minerals to the soil. Before UNDO, Jim started the Future Forest Company. UNDO’s buyers include Microsoft, Barclays, and British Airways, and the company is expanding across the Canadian prairies. Farm Credit Canada invested in UNDO in 2025. About Brodie Berrigan: Brodie Berrigan is senior director of government relations and farm policy at the Canadian Federation of Agriculture, the largest farm organization in the country. He works the files that keep producers up at night: business risk management, food security, labour, trade, and transportation. Before the CFA, he spent years in the federal government at Public Services and Procurement, the Privy Council Office, and Employment and Social Development. About UNDO: UNDO uses enhanced rock weathering to permanently remove CO2 by spreading crushed silicate rock on farmland. The company works with existing farm equipment and existing extraction sites, and it sells durable carbon removal to corporate buyers. Learn more at un-do.com. About the Canadian Federation of Agriculture: The CFA is Canada’s largest general farm organization. Its members include provincial and territorial farm groups and national commodity associations. It represents about 190,000 farmers and farm families in Ottawa. The wider agri-food system employs about 2.3 million people and generated about $150 billion in GDP in the year Brodie cites. This episode was made possible thanks to the generous support of the Consecon Foundation. This episode was created and published by Na’im Merchant. Episode production and content support provided by Daniel Kelter and Tank Chen. Na’im Merchant is the co-founder and Executive Director of Carbon Removal Canada, a policy initiative focused on scaling carbon removal in Canada. He is on the advisory board of the Carbon Removal Standards Initiative and Terraset, and a former policy fellow with Elemental Impact. He previously ran carbon removal consulting practice Carbon Curve, and publishes The Carbon Curve newsletter and podcast. This episode is part of Carb
Episode 67 is with Dr. Joachim Katchinoff, Co-founder and CEO of CREW Carbon In this episode, Na’im speaks with Dr. Joachim “Jo” Katchinoff, co-founder and CEO of CREW Carbon, about how wastewater treatment plants can become permanent carbon sinks. Jo explains how dosing calcium carbonate into wastewater bioreactors converts microbe-produced CO2 into stable bicarbonate, why closed treatment systems make measurement far easier than open-ocean approaches, how the same intervention helps utilities remove more nitrogen and phosphorus while deferring major capital upgrades, what it takes to scale in a slow-moving regulated sector, and more. This conversation was recorded before some big news from CREW: the company just signed an offtake agreement with Microsoft for up to 23,602 durable carbon removal units — bringing CREW to more than $40 million in committed carbon removal contracts with buyers including JP Morgan, Google, Autodesk, and Stripe through Frontier. It’s a strong signal that the approach Jo describes in this episode is resonating with the market’s most demanding buyers. Na’im and Jo discuss: * Jo’s Journey From Environmental Consulting To Yale * Commercializing Alkalinity-Based Carbon Removal * How Wastewater Treatment Actually Works * Wastewater Alkalinity Enhancement Explained * MRV Advantages Of Closed Reactor Systems * Co-Benefits For Wastewater Utilities * Scaling In A Regulated, Risk-Averse Sector * What Policymakers Need To Know * CREW’s Series A And What’s Next Relevant Links: * CREW Carbon - Website * Wastewater Alkalinity Enhancement - CREW’s Approach * CREW Carbon Signs Offtake Agreement with Microsoft for Wastewater Carbon Removal * Isometric’s Certified Protocol for Carbon Removal via Wastewater * CREW Carbon and Isometric Announce the World’s First Wastewater Alkalinity Enhancement Carbon Removal Credits About Jo Katchinoff: Jo is the co-founder and CEO of CREW Carbon, a scientist with multiple patents and over a decade in environmental research and climate modeling. Jo leads CREW’s scientific strategy, partnerships, and commercialization of a novel platform that lets wastewater facilities remove and permanently store atmospheric carbon dioxide. Previously, Jo was a postdoctoral researcher and project manager at Yale, where his work on alkalinity-based carbon removal laid the scientific foundation for CREW’s platform. During his PhD at Yale’s Earth and Planetary Sciences Department, he published in journals like Nature and won the Hammer Prize for Outstanding Geologist. He was also a Marie Curie Fellow at Oxford, studying weathering and carbon dioxide removal. He holds a PhD and MPhil from Yale and a BS in Earth Science from William & Mary. About CREW Carbon: Founded in 2022 out of Yale University, CREW Carbon is a water technology company providing wastewater treatment facilities with a solution that improves performance, lowers cost, and permanently removes greenhouse gases. By dosing carbon-negative alkalinity like calcium carbonate directly into wastewater bioreactors, CREW captures biogenic CO2 as stable bicarbonate while improving biological treatment efficiency. CREW is now deployed at 10 wastewater treatment facilities across the US and Europe, has raised over $35 million in funding including a recent Series A, and holds more than $40 million in committed carbon removal contracts with buyers including Microsoft, JP Morgan, Google, Autodesk, and Stripe through Frontier. You can learn more at crewcarbon.com. This episode was made possible thanks to the generous support of the Consecon Foundation. This episode was created and published by Na’im Merchant. Episode production and content support provided by Tank Chen. Na’im Merchant is the co-founder and Executive Director of Carbon Removal Canada, a policy initiative focused on scaling carbon removal in Canada. He is on the advisory board of the Carbon Removal Standards Initiative and Terraset, and a former policy fellow with Elemental Impact. He previ
Episode 66 is with Richard Barker, Partner at Counteract In this episode, Na’im speaks with Richard Barker, a partner at Counteract, about why financing models vary widely by pathway, capex/opex profile, and deployment context. Richard highlights industrial integration opportunities, the need for team and financial readiness for long corporate timelines, how policy should set stable expectations akin to landfill tax, and more. Na’im and Richard discuss: * Richard’s Journey Into Climate Investing * Counteract’s Investment Thesis * Financing Models Evolving * CDR Pathways With Industrial Fit * Financing In Tight Markets * Preparing Startups To Scale * Lessons From Other Industries * Policy Expectations And Demand * Counteract Next Delivery Fund Relevant Links: * Counteract - Website * Counteract’s Portfolio Companies About Richard Barker: Richard is a Partner at Counteract. His varied experience spans over 35 years and working in a number of countries. He studied engineering at Oxford University, before lecturing in Economics at UCC in Ireland. After spells in strategic consulting and as Head of Strategy at ANZ Investment Bank in Australia, Richard founded and grew a number of sustainable businesses - in chemical process technology, aluminium recycling and biomethane - before moving onto the investment side about 10 years ago. He has advised a number of investors on sustainable infrastructure investment before joining Counteract. About Counteract: Founded in 2021, Counteract was the world’s first early stage investor dedicated to carbon removals. They’re a team of experienced entrepreneurs who saw a huge opportunity in an overlooked part of climate. The team has looked at over 1,000 companies on its journey to investing in 27 companies to date - diverse by both geography and CDR pathway. This, together with Counteract’s own research capability, puts it at the centre of this nascent market with unparalleled knowledge and a strong reputation within the CDR ecosystem This episode was made possible thanks to the generous support of the Consecon Foundation. This episode was created and published by Na’im Merchant. Episode production and content support provided by Tank Chen. Na’im Merchant is the co-founder and Executive Director of Carbon Removal Canada, a policy initiative focused on scaling carbon removal in Canada. He is on the advisory board of the Carbon Removal Standards Initiative and Terraset, and a former policy fellow with Elemental Impact. He previously ran carbon removal consulting practice Carbon Curve, and publishes The Carbon Curve newsletter and podcast. Every two weeks, Na’im will release a short interview with individuals advancing the policies, technologies, and collective action needed to scale up carbon removal around the world. Tank Chen is the Head of Content and Community at CDR.fyi, a public benefit corporation dedicated to accelerating carbon removal through transparency. He is also the co-founder of CDRjobs, a career platform for the carbon removal industry. Based in Taiwan, Tank is a carbon removal advocate focused on educating policymakers, corporate leaders, and the public on the importance of carbon removal, using data-driven insights to support communication and policy advocacy. If you enjoyed this episode, please subscribe to this podcast on your favorite podcast app or subscribe via The Carbon Curve newsletter here. If you’d like to get in touch with Na’im, you can reach out via LinkedIn.