Why Circularity Fuels Started with Diamonds to Scale Sustainable Jet Fuel

Dr. Stephen Beaton is Co-founder and CEO of Circularity Fuels, which develops compact reactors that turn waste carbon streams into high-value fuels and chemicals. Rather than compete with fossil fuels from the start, Stephen identified high-purity methane for lab-grown diamonds as a beachhead market—where Circularity’s product is 80–90% cheaper than incumbents while proving the core technology needed for clean liquid fuels.Stephen earned a chemistry PhD at Oxford and built deep expertise in synthetic fuels during his U.S. Air Force career, including overseeing jet fuel quality control in the Middle East and launching the Air Force’s e-fuels program. His insight: build a fuels company that doesn’t begin with fuel.Today, Circularity Fuels operates demonstration reactors in diamond facilities and is scaling toward biogas-to-SAF production using the same reactor platform. The company has raised $3M in venture funding, including from DCVC, plus $5M in grants from ARPA-E, NSF, and the California Energy Commission. MCJ is proud to be an investor.Episode recorded on Aug 12, 2025 (Published on Sept 16, 2025)In this episode, we cover: [03:09] Dr. Beaton’s background in clean fuels[07:31] His work with Air Force petroleum in the Middle East[10:12] A brief overview of hydrocarbons[13:08] ESAF as resilience for Pacific operations[16:22] What e-SAF really means and why it matters[19:24] Circularity Fuels’ origin story[21:20] The company’s three principles[23:04] High-purity methane for diamonds as a beachhead[27:46] Recycling diamond exhaust with microwave-sized reactors[30:40] Building a fuel company without fuel as the initial product[34:35] Hardware sales vs metered methane service model[39:05] Biogas-to-SAF pathway via Fischer-Tropsch[42:38] Circularity’s progress to date[44:01] Competing with fossil jet and carbon removals[48:41] How Circularity secured non-dilutive funding Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Marc Tarpenning is Co-founder of Tesla and a venture partner at Spero Ventures. In 2003, Marc and Martin Eberhard saw two signals: GM killed its beloved EV1, and Californians snapped up Toyota’s Prius despite its compromises. They realized the market was ready for an electric car that was better than gas, not worse. Their breakthrough: 7,000 off-the-shelf laptop batteries powering a sports car that outran a Porsche and drove over 200 miles. The Tesla Roadster was born, before Elon Musk joined the company.Marc shares how his time in Saudi Arabia exposed him to oil dependence, how NuvoMedia taught him about the pace of battery improvement, and why a software mindset helped Tesla out-innovate incumbents. Now at Spero Ventures, Marc backs founders building solutions that are both economically compelling and environmentally vital, and explains why, to him, EVs have already won.Episode recorded on Aug 12, 2025 (Published on Sept 9, 2025)In this episode, we cover: [05:58] Marc's experience fixing software projects in Saudi Arabia[07:06] Why TELO’s compact electric pickup makes sense[09:09] Marc's Star Trek optimism versus Blade Runner dystopia[10:29] On founding NuvoMedia and the first e-book readers[17:40] Brainstorming EVs after the dot-com collapse[20:25] Prius demand proves customers value efficiency[22:18] Reducing oil dependence as national security[24:46] Roadster powered by 7,000 laptop lithium-ion cells[30:28] The Tesla launch playbook[32:14] Acceleration as the hook for high-end EV buyers[37:20] Early interactions with Elon Musk at SpaceX office[40:11] Lessons from early Roadster builds[43:36] Vertical integration only where it truly differentiates[48:15] Why EVs are inevitable[50:30] Marc's thoughts on Tesla today Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Dr. Susan Hubbard is Deputy Director for Science and Technology at Oak Ridge National Laboratory, the largest of the U.S. Department of Energy’s multi-program science and energy labs. With more than 7,000 scientists and engineers, Oak Ridge is advancing innovation across nuclear energy, grid resilience, AI, quantum computing, isotopes, and advanced manufacturing. In this episode, Susan shares how the national labs’ mission has evolved since the Manhattan Project, how companies and startups engage with Oak Ridge through user facilities and partnerships, and what role the labs will play in shaping the future of energy and technology amid today’s geopolitical and industrial shifts.Episode recorded Aug 18, 2025 (Published Sept 2, 2025) In this episode, we cover: [03:03] Dr. Hubbard’s early career and hydrogeophysics[05:31] Permafrost thaw in the Arctic[07:11] Earth system complexity[09:00] Transition from geophysicist to ORNL leadership[12:17] ORNL’s user facilities, including Frontier supercomputer[13:56] Isotopes for medicine, security, and Mars exploration[15:45] Neutron scattering and world-leading materials research[17:25] Large-scale 3D additive manufacturing for energy[19:25] How DOE priorities shape research directions[22:04] Public-private partnerships in nuclear and fusion[26:54] ORNL’s role in ITER and advanced fusion materials[30:51] Local enthusiasm for nuclear in Tennessee[31:54] Building the future grid: reliability, cybersecurity, AI[33:17] High-performance computing simulations of energy systems[37:23] Quantum computing, AI, and labs of the future[43:41] How startups engage with ORNL (CRADA, Innovation Crossroads)[48:02] U.S. R&D evolution: Manhattan Project to today Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Mitch Lee, CEO of Arc Boat Company, is bringing the Tesla playbook to boating. Arc’s quiet, software-powered electric boats—like the sold-out Arc Sport—deliver cleaner rides, zero fumes, and customizable wave settings. Mitch shares why electric makes more sense on water than land, how dockside charging already works, and why Arc builds full boats instead of motors. With $100M raised and an expansion into commercial vessels, Arc is leading a cleaner, better future for marine travel.Episode recorded on Aug 6, 2025 (Published on Aug 12, 2025)In this episode, we cover: [3:27] An overview of Arc Boat Company [5:07] Mitch’s background and experience ⁠[6:28] The inefficiency of gas boats and fuel use[8:17] His decision to build Arc [10:54] The company’s vertically integrated battery pack ⁠[12:04] Why Arc builds complete boats, not just motors⁠[13:31] Battery size, range, and charging times for Arc boats[16:36] Charging Arc boats [19:26] The traditional boat market and Arc's advantage[24:26] Safety on Arc boats ⁠[28:51] Lessons from Arc One to Arc Sport⁠[33:20] Software-driven customization for water sports⁠[39:19] Arc Coast’s design and target market⁠[41:30] Expansion into commercial and hybrid-electric vessels[44:21] Why the US hasn’t electrified commercial vessels like ferries ⁠[49:06] $100M raised from top VCs and celebrity investors Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Katherine Boyle and Erin Price-Wright are General Partners at Andreessen Horowitz (a16z), leading the firm's American Dynamism practice. This episode explores how their team invests in companies tackling national imperatives—ranging from defense and manufacturing to energy and critical infrastructure. Katherine shares how American Dynamism emerged from portfolio patterns at a16z, while Erin describes how her background at Palantir informs her investment lens. Together, they unpack why the U.S. must reindustrialize, how software is now eating the physical world, and what they look for in high-capex startups. This conversation also highlights the evolving U.S.-China industrial competition, the role of government in innovation, and why talent is moving from Big Tech into “hard tech.”In this episode, we cover: ⁠[02:30]⁠ An overview of a16z⁠[04:59]⁠ Its thesis shift from defense to energy and industry⁠[07:49]⁠ How AI is transforming heavy industries[8:24] Tech stack for US vs. China[12:23]⁠ Role of government versus private capital⁠[16:14]⁠ Why software is still the core of industrial innovation[16:55]⁠ Base Power as a software-led grid infrastructure play⁠[20:42]⁠ When vertical AI-native startups beat incumbents⁠[21:48]⁠ How a16z helps startups navigate Washington⁠[27:51]⁠ Why energy problems require system-level solutions⁠[31:57]⁠ Moats in energy and manufacturing[37:51] a16z’s American Dynamism 50 list⁠[40:16]⁠ Battery supply chains and the China dependency⁠[46:44]⁠ Why capital stack strategy matters for hard tech founders⁠[48:52]⁠ Looking 10 years aheadEpisode recorded on May 21, 2025 (Published on July 29, 2025) Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Dr. Michael Mann is Presidential Distinguished Professor of Earth and Environmental Science at the University of Pennsylvania. He also serves as Director of the Penn Center for Science, Sustainability, and the Media, and Vice Provost for Climate Science Action and Policy.Dr. Mann first entered the public consciousness in the late 1990s with his "hockey stick graph," a reconstruction of Earth’s climate history over the past 1,000 years. The graph became both a cornerstone of climate science and a lightning rod for controversy. Since then, he has published more than 200 peer-reviewed papers, co-founded realclimate.org, and written five books—most recently, Our Fragile Moment: How Lessons from Earth’s Past Can Help Us Survive the Climate Crisis.Having spent nearly three decades fighting climate misinformation and defending the scientific record, Dr. Mann has witnessed multiple waves of public consciousness around climate change. In this episode, we hear his perspective on how public sentiment has evolved, where we stand today, and his views on what he sees as a coordinated campaign to block climate action.Dr. Mann doesn’t pull punches. He names names, draws direct lines between fossil fuel interests and political actors, and isn’t shy about calling out what he views as bad-faith tactics across the political spectrum.Episode recorded on May 21, 2025 (Published on Jul 22, 2025)In this episode, we cover: ⁠[1:51]⁠ DiCaprio based Don’t Look Up character on Michael⁠[4:26]⁠ Why Michael’s center combines science and media⁠[5:27]⁠ Communication is today’s biggest climate challenge⁠[7:27]⁠ The story and impact of the “hockey stick” graph⁠[13:17]⁠ How fossil fuel interests targeted his work and reputation⁠[15:32]⁠ Russia’s modern climate disinformation tactics⁠[17:22]⁠ Climate denial, delay, doom, distraction, and division⁠[20:26]⁠ Deflection: blame shifted to individual responsibility⁠[21:48]⁠ The progress we’ve made and the need to accelerate solutions⁠[25:17]⁠ Why China may lead in future emissions reductions⁠[29:16]⁠ Methane leaks make gas a major climate threat[33:15] What exactly we’re trying to save on the planet⁠[38:22]⁠ How Project 2025 is erasing climate accountability⁠[40:46]⁠ Which climate science institutions are being dismantled⁠[45:09]⁠ What a livable 2050 future could still look like Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Dr. Mark Jacobson is a professor of Civil and Environmental Engineering and Director of the Atmosphere Energy Program at Stanford University, where he’s been one of the most vocal advocates for powering the world entirely with wind, water, and solar energy. No nuclear, no carbon capture, no fossil fuels of any kind. His research team has created 100% renewable energy roadmaps for all 50 U.S. states and 149 countries, helping shape policies like New York’s clean energy mandate. In this episode, Dr. Jacobson shares his perspective on where we are in the renewables adoption curve and explains why he believes that technologies like nuclear power, carbon capture, and biofuels aren’t just unnecessary, they’re harmful distractions from the clean energy transition he sees as both achievable and urgent.This conversation may be polarizing. While many will agree with Mark's take on renewables and the grid, his firm rejection of other low-carbon tech challenges mainstream climate thinking. We believe these fault lines are worth exploring, even, or especially, when they make people uncomfortable.Episode recorded on June 30, 2025 (Published on July 15, 2025)In this episode, we cover: ⁠[02:32]⁠ Why proposed tax changes threaten renewables⁠[05:45]⁠ Fossil fuel subsidies vs. renewables support⁠[06:29]⁠ China’s rapid clean energy deployment⁠[10:44]⁠ Rooftop solar offsets California’s rising demand⁠[12:20]⁠ Home and utility batteries reshaping grid usage⁠[14:40]⁠ Texas grid inefficiencies and renewables progress⁠[18:21]⁠ Combining wind, solar and batteries[19:26]⁠ Land use myths about wind and solar[22:49] Dr. Mark Jacobson’s background and research⁠[27:23]⁠ How to phase out existing fossil infrastructure⁠[31:36]⁠ Dr. Jacobson’s rejection of carbon capture[36:52] His thoughts on nuclear[42:11] Dr. Jacobson’s thoughts on geothermal[46:19] How he sees the next decade unfolding Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Suvi Sharma is the CEO and Co-Founder at SOLARCYCLE. SOLARCYCLE is an emerging leader in the nascent category of solar panel recycling. The astounding ramp of solar panels deployed across the world rivals almost any technology adoption curve in history, and it's far from over. There were only five gigawatts of solar deployed globally between 2000 and 2005. By the end of 2025, a mere 20 years later, there will be around 2,000 gigawatts of solar deployed globally, and the growth is expected to continue to be exponential. That's billions and billions of panels that collectively make up a few hundred thousand square miles of space. And given the rate of installation, most of these panels are early in their expected lifespans. So, what happens when they do hit the end of life? Surely they aren't going to just be landfilled, right? Right? That's what Suvi's here to about. In this episode, we cover: ⁠ [01:16]⁠ Solar panel deployment vs. end-of-life lag⁠[03:40]⁠ Billions of panels, billions of square feet⁠[05:11]⁠ 1.2B panels produced annually—set to triple⁠[07:06]⁠ Why is now the time to build recycling⁠[08:36]⁠ Who’s responsible for end-of-life? Developers[9:36] Federal and state regulatory requirements⁠[10:46]⁠ Why landfilling is harder than it looks⁠[12:44]⁠ What makes solar panels tough to recycle⁠[14:01]⁠ The high-value metals: silver, copper, aluminum⁠[16:17]⁠ How SOLARCYCLE’s proprietary process works[18:01] The company’s customer base⁠[19:18]⁠ Over 1M panels recycled in 2024⁠[20:44]⁠ Future opportunities in solar + storage recycling[21:57] SOLARCYCLE’s funding to date[24:55] Commodity markets for recycled materials[26:39] What’s holding back growth for panel recycling[30:05] SOLARCYCLE is hiring⁠[33:54] Panels as feedstock materials for domestic manufacturingEpisode recorded on May 22, 2025 (Published on June 30, 2025) Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Haakon Brunell is the CEO and Co-founder of Carbon Crusher, a Norwegian company turning traditional road construction on its head. Carbon Crusher refurbishes existing roads using bio-based binders and on-site recycling to create carbon-negative, cost-effective, and more durable infrastructure. In this episode, Haakon shares how their "Crushing-as-a-Service" model and SkyRoads AI platform reduce emissions, increase road longevity, and drive down costs. He explains why roads are both a climate problem and a climate opportunity—and how Carbon Crusher plans to sequester a gigaton of CO₂ by 2035.MCJ is an investor in Carbon Crusher, having participated in the company's seed round back in 2022 when it emerged from Y Combinator. Guest hosting for the first time on this episode is MCJ Partner, Thai Nguyen. Enjoy the show! In this episode, we cover: [02:23] Launching Carbon Crusher out of Y Combinator[05:22] An overview of Carbon Crusher[06:15] Roads as a climate problem and carbon sink opportunity[08:21] Emissions from traditional road refurbishment[09:41] Carbon Crusher's 3 pillars: crushing, bio-binders, and AI platform[12:52] Why roads are now stronger, cheaper, and greener[14:14] Customer mindset in a conservative industry[17:49] Origin story from winter-damaged roads in Norway[21:12] Performance in both cold and hot weather climates[22:53] Customers include cities, counties, and private road owners[26:12] SkyRoads AI helps digitize and plan road maintenance[28:45] Challenges: regulation and conservative decision-making[30:53] Vision: sequestering a gigaton of CO₂ by 2035Episode recorded on May 13, 2025 (Published on June 23, 2025) Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant

Cully Cavness is the co-founder, president, and COO of Crusoe, an energy-first AI infrastructure company. In this live episode recorded in Austin, Texas, Cully shares how Crusoe evolved from capturing flared gas for Bitcoin mining to becoming a leading developer of hyperscale data centers. He discusses the company’s pivotal role in Project Stargate—a $500B AI infrastructure effort led by OpenAI, SoftBank, and Oracle—and how Crusoe is building a 1.2 gigawatt data center campus in Abilene, Texas. Cully reflects on the decision to divest its original Bitcoin business, the company’s vertical integration strategy, and how energy abundance will shape the future of AI. Thanks to our sponsors for this event: Gunderson Dettmer, and J.P. Morgan.In this episode, we cover: ⁠[00:24]⁠ An overview of Crusoe⁠[01:08]⁠ Its role in Project Stargate and Abilene data center⁠[03:41]⁠ Shift from outbound to inbound interest⁠[06:17]⁠ Company pivots and existential startup bets[09:09]⁠ Sale of Bitcoin mining business to NYDIG[11:40]⁠ Flared gas capture and climate impact overview⁠[14:57]⁠ From digital flare mitigation to stranded wind use⁠[17:27]⁠ Cully’s personal energy background and worldview⁠[22:14]⁠ Why AI could drive climate and fusion breakthroughs⁠[25:47]⁠ Details of the 1.2 GW Abilene campus for Oracle⁠[36:42]⁠ 3,500 skilled trades supporting data center build⁠[44:42]⁠ Natural gas as a bridge fuel + CCS investmentsEpisode recorded on June 10, 2025 (Published on June 17, 2025) Enjoyed this episode? Please leave us a review! Share feedback or suggest future topics and guests at [email protected] with MCJ:Cody Simms on LinkedInVisit mcj.vcSubscribe to the MCJ Newsletter*Editing and post-production work for this episode was provided by The Podcast Consultant