[Part 1] Eric Bosworth - Manager of Clean Technology at Eversource

Mike Eros - Chief Geoscientist of Sage Geosystems

In this episode, we’re diving into the world of subsurface energy storage and geothermal power with Mike Eros [https://www.linkedin.com/in/mike-eros-ab3509a9/], Chief Geoscientist at Sage Geosystems [https://www.sagegeosystems.com/], where he’s pioneering geo-pressured geothermal and long-duration energy storage solutions. A former ExxonMobil subsurface expert, he’s now helping reshape how we tap into and store Earth’s heat. We explore how Mike transitioned from oil and gas into geothermal, the potential of geo-pressured systems for grid-scale power and storage, and Sage Geosystems’ groundbreaking projects reshaping the future of energy. Episode At-a-Glance * Storage + Geothermal: Sage merges long-duration pressure storage with geothermal heat extraction — delivering baseload + peaking power from the same well. * From O&G to Geo: Subsurface and drilling skills transition directly into geothermal; the biggest bottleneck is industry awareness, not ability. * EarthStore Pilot: First 3 MW project in Texas test results showing 70–75% storage efficiency with <2% fluid loss — built using off-the-shelf drilling tools. * DoD + Meta: Early customers want resilience (military bases) and 24/7 clean power (data centers). * Ormat Partnership: Taps into existing interconnections and Ormat’s equipment procuring capabilities — potentially reducing geothermal timelines from years to months. * Superhot Roadmap: Drill to ~16,000 ft, then frack deep to access 300°C rock for 10× power density using mostly standard oil & gas gear. * The Big Blockers: Organic-Rankine Cycle (ORC) turbine and broader equipment delays, interconnection queues, and lack of drilled pilots — not geology. ⏱️ Timestamps (Notes below) [1:04] What got Mike into Geothermal? What was his career? [6:14] How do Sage’s Pressured Geothermal Systems work? [16:59] Why do we push the working fluid lung-like “huff-n-puff” operations in fractures? [21:06] What are the variables affecting the economics on your projects and the efficiencies on your storage projects? How can we make geothermal scale faster? [29:55] How does your team measure success? What are the longer term goals? [33:57] How is your team exploring using super critical CO2 as a working fluid? [36:15] What does it look like to build out a Sage site from ideation to creation? [40:59] How is your team engaging with different partners to get things done? [43:07] What are the risks and challenges your team is facing? [45:58] How does financing these different projects look? [49:54] How does your team work with different locales to help integrate projects with the community? What about other regulatory frameworks and environmental risks your team has to handle? [59:31] How are the steps back in supporting certain renewables like wind and solar impacting your team? [1:04:49] Lessons from working with San Miguel Electric Cooperative and ERCOT [1:11:07] How is your team approaching permitting in regards to your work in Altascosa County? [1:13:50] How has your team been approaching the grid interconnection process? [1:15:22] Digging in on the project with the US Air Force in Starr County. [1:19:07] How is your team developing and navigating partnerships with other military branches and the broader US military? [1:22:31] Sage and Meta’s partnership and how the team is approaching it. [1:25:59] Partnership with Ormat in the west. [1:29:29] Where do you see this partnership with Ormat going? [1:31:50] How have technological advancements in energy and drilling contributed to geothermal today? [1:40:08] How can we get communities and the government more excited about geothermal? What can they do to help? [1:45:18] What’s coming up for Sage? [1:48:23] If you had a magic wand, what problem in geothermal would you solve today? Additional Notes * Regarding 10 to 20% dilation - As an additional note, the larger the volume put in the ground compared to the percent that is brought out/smaller volumes allows the system to stay above fracture opening pressure. This maintains sufficient presssure in the fracture to keep the system open without proppant. * Regarding the mention of $0.065/kWh - Mike misspoke on the 10-12 cents. He meant that the costs would fall to the lower side with scale with a target of 6 to 7 cents per kWh. Additionally, for energy storage, the team is targetting Long-duration CAPEX of $2.25M/MW. 🔬 Sage’s Tech: What Makes “Geo-Pressured Geothermal” Unique? If you’re new to Sage, their system is: part geothermal, part inverted pumped hydro. Instead of just drilling into hot dry rock and circulating water, they: * Drill mostly vertical wells, with a short deviation. * Create a lung-shaped fracture network beneath the surface. * Cycle fluid in a “huff-and-puff” pattern—injecting to build pressure, then releasing it to run a surface turbine. Where it fits in: * 8-12 hour duration long-term storage * Ideal for solar-heavy regions like Texas & California, as well as Australia * Cheaper + higher energy density than lithium-ion beyond 4 hour discharge durations So far, this has led to: * Round-trip storage efficiencies of ~70–75% (on par with lithium-ion and pumped hydro). * Low fluid loss (<2%)—critical for long-term operation and environmental confidence. This is different from some of the other well-known players as well: * Fervo Energy [https://fervoenergy.com/]: Prioritizes inter-well fracture connectivity for heat extraction (not pressure cycling). * Quidnet [https://quidnetenergy.com/]: Works at shallower depths with “pancake fractures” for subsurface storage, not geothermal heat. * Exceed GeoEnergy [https://exceedgeoenergy.com/]: Aims for closed-loop systems using CO₂ as the working fluid. (Check out our episode with the founder, Tim Tarver, here [https://geothermalweekly.substack.com/p/tim-tarver-founding-board-member]) * Mazama Energy [https://mazamaenergy.com/] (and DOE superhot initiatives [https://arpa-e.energy.gov/programs-and-initiatives/view-all-programs/superhot]): Pursue ultra-deep drilling into 300+°C rock—potentially ≥10x power output. A future goal for Sage as well. Sage, in contrast, is finding a viable bridge: using standard drilling tech and tools from oil and gas to unlock deep baseload power and grid-scale storage. 🧪 Project Highlights — More Than Just Pilot Talk One of the most exciting things to note is how quickly Sage has moved from theory to real projects: ✅ EarthStore #1 – San Miguel Electric Coop (South Texas) [http://www.smeci.net/blog/san-miguel-electric-cooperative-inc-to-leverage-new-low-emission-energy-sources-at-its-south-texas-power-plant] * 3 MW energy storage pilot project co-located with a coal plant with plans for 400 MW solar expansion * Targeting Q1 2026 grid interconnection with ERCOT * First-of-its-kind subsurface storage system using off-the-shelf turbines * 12-month delivery from drilling to facility commissioning With this built, Sage now has a pad that could support 10+ wells and >50 MW of long-duration storage—all without the need for mountainous terrain, vast water imoundment, and long permitting times that traditional pumped hydro requires. 🛡️ Department of Defense Partnerships Sage has leveraged their existing work to further build projects with the DoD. * Sage has completed geothermal feasibility study with UT Austin’s Bureau of Economic Geology (BEG) at [https://www.beg.utexas.edu/articles/bureau-of-economic-geology-to-undertake-study-to-develop-geothermal-energy-at-ellington-air-force-base]Joint Base Ellington [https://www.beg.utexas.edu/articles/bureau-of-economic-geology-to-undertake-study-to-develop-geothermal-energy-at-ellington-air-force-base]. (Hear more about the Bureau of Economic Geology wiht our episode with Ken Wisian (Part 1 [https://geothermalweekly.substack.com/p/part-1-ken-wisian-associate-director], Part 2 [https://geothermalweekly.substack.com/p/part-2-ken-wisian-associate-director]) * They’ve been awarded $1.9M toward a real geothermal power demonstration. * Parallel work is now happening at Fort Bliss [https://www.businesswire.com/news/home/20240417549482/en/Sage-Geosystems-to-Advance-Energy-Resilience-with-Geothermal-Energy-Solutions-at-Fort-Bliss] (Army) [https://www.businesswire.com/news/home/20240417549482/en/Sage-Geosystems-to-Advance-Energy-Resilience-with-Geothermal-Energy-Solutions-at-Fort-Bliss] and Naval Air Station Corpus Christi [https://www.businesswire.com/news/home/20241003555153/en/Sage-Geosystems-Expands-Collaboration-with-the-DoD-to-Enhance-Energy-Resilience-through-Geothermal-Energy-at-Naval-Air-Station-Corpus-Christi] (Navy) [https://www.businesswire.com/news/home/20241003555153/en/Sage-Geosystems-Expands-Collaboration-with-the-DoD-to-Enhance-Energy-Resilience-through-Geothermal-Energy-at-Naval-Air-Station-Corpus-Christi]. * Priority: “behind-the-fence” power resilience to ensure bases can operate even if the external grid fails. Thank you for reading The Geothermal Energy Newsletter! Subscribe for free to receive new posts and support our work. 🧠 Meta & Ormat: Strategic Scale, Not Just Experiments Sage isn’t just proving the tech—they’re anchoring it with serious partners: * Meta (Facebook) [https://about.fb.com/news/2024/08/new-geothermal-energy-project-to-support-our-data-centers/] * Target: 4–8 MW geothermal by 2027, with paths to scale to 150 MW and beyond. * Location: east of the Rockies (think grid-challenged, heat-rich regions). * Goal: 24/7 clean power for hyperscale AI data centers. * Ormat Technologies [https://investor.ormat.com/news-events/news/news-details/2025/Ormat-Technologies-Announces-Strategic-Commercial-Agreement-With-Sage-Geosystems-Inc-/default.aspx] * Why this matters: Ormat owns dozens of operating geothermal plants already connected to the grid. * This deal enables Sage to deploy their subsurface system into existing power sites—bypassing long lead times for interconnection and key equipment procurement. * Mike thinks this could cut their first full-scale geothermal project timeline from several years to as little as 12–18 months. 🌱 Risk, Regulation & Water: How They’re Meeting Community Expectations Geothermal always raises good questions about water use and induced seismicity. Here’s how Sage is addressing those: * Water sourcing: Using non-potable sources, including ranch and industrial water; modeling even wastewater use in future systems. * Seismic transparency: Partnered with UT’s TexNet [https://texnet.beg.utexas.edu/] seismic network, run by the Bureau of Economic Geology to ensure independent monitoring. * Fluid loss: Maintaining <2% loss is key—not just for safety, but economics based on higher system efficiencies and lower costs. 📊 Economics: What Moves the Needle The biggest costs in geothermal are: * Drilling and stimulation * ORC procurement (18+ month lead times) * Interconnection delays But Mike made it clear:✅ Pair geothermal + storage with solar → competitive LCOE: $60–70/MWh✅ Scale from a single-well pad to multi-well → drive down cost/kW✅ Bundle into confirmed PPAs → unlock project finance instead of venture equity 🪄 Mike’s Magic Wand: More Drilling, Less Modeling Mike’s #1 concern for geothermal right now? Funding. “You know, if I could instantly give all of the companies that have a brilliant idea, the money that they need to test, I would do it. There aren’t that many players on the field who actually [have] a drill ready proposal. I would do that immediately. Why beat around the bush? Let’s learn together quickly.” What’s missing: * Fast, catalytic funding to drill and prove commercial viability * Public support stalled since the 1970s (For a broader history of geothermal, read more here [https://www1.eere.energy.gov/geothermal/pdfs/geothermal_history_1_exploration.pdf]) * Most investors need to see more commercial successes Bright spots: * Rising demand from data centers and utilities for 24/7 clean power * New Energy Secretary showing interest [https://www.thinkgeoenergy.com/u-s-energy-secretary-chris-wright-endorses-geothermal-expansion/] * A few successful pilots could unlock a wave of private capital 🔗 Recommended Episodes * Tim Tarver (Exceed GeoEnergy) [https://open.substack.com/pub/geothermalweekly/p/tim-tarver-founding-board-member?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] — Advanced geothermal drilling, fracking challenges, and water reuse. * Jen Wakeland (Beaver County, Utah) [https://open.substack.com/pub/geothermalweekly/p/jen-wakeland-strategic-development?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] — Community engagement, rural development, and transmission planning. * Bill Heins (Getech) [https://open.substack.com/pub/geothermalweekly/p/bill-heins-chief-geoscientist-of?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] — Insurance products and de-risking geothermal projects in Europe. * Eric Bosworth (Eversource) (Part 1 [https://open.substack.com/pub/geothermalweekly/p/part-1-eric-bosworth-manager-of-clean?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false], Part 2 [https://open.substack.com/pub/geothermalweekly/p/eric-bosworth-manager-of-clean-technology?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false]) — Utility-led networked geothermal and lessons from the Framingham pilot. * Ken Wisian (Bureau of Economic Geology, Texas) (Part 1 [https://open.substack.com/pub/geothermalweekly/p/part-1-ken-wisian-associate-director?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false], Part 2 [https://open.substack.com/pub/geothermalweekly/p/part-2-ken-wisian-associate-director?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false])— Military applications of geothermal and energy security. This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit geothermalweekly.substack.com [https://geothermalweekly.substack.com?utm_medium=podcast&utm_campaign=CTA_1]

Tim Lines - CEO of Geothermal Wells, Geothermal Evangelist

In this episode, we sit down with Tim Lines [https://www.linkedin.com/in/tim-lines-1894b810/], a petroleum engineer turned geothermal advocate, whose career spans 40+ countries in oil & gas, district heating, and now geothermal innovation. We explore how he was drawn into the sector, the technical-economic feasibility of geothermal at scale, and his company’s work to advance projects in the UK and abroad. ⏱️ Timestamps * 00:00 - Introduction, What led Tim to geothermal and why now? Exploration of future of geothermal energy * 7:08 - Breaking down more of the future of geothermal in Texas report * 12:30 - How are current technologies trying to solve the heat issues for drilling with geothermal? What can other geothermal developers learn? * 17:32 - Digging into different drilling fluids and which make more sense to use * 21:20 - How can we get better at processing and reducing errors in sensing data in the context of geothermal drilling? * 23:57 - European SPE Geothermal Energy Hackathon * 28:48 - How have your assumptions about geothermal energy changed as you’ve been involved in the field? Tim also discusses one of the projects he’s been working on in the UK and discusses the different partners and techniques he’s used to find success * 41:09 - Discussing how drilling and fracking has changed from the 90s to today * 46:05 - How can we keep pricing for geothermal competitive? What political and economic tools are available? * 52:40 - Examples of countries doing great jobs with feed in tariffs for geothermal * 59:28 - How can we work with local partners to create unique solutions to water problems for geothermal? (in this case, Tim worked with local municipalities to build a reservoir) * 1:07:03 - What are the challenges of bringing American drilling technologies abroad? * 1:10:52 - Who are the different segments of customers for geothermal projects? What are their differing needs? * 1:23:57 - What are the different challenges with customer discovery for geothermal? What tools are out there? * 1:28:56 - What are the challenges to getting different offtakers involved? How can we get them excited about geothermal? * 1:30:48 - How do American and international offtakers differ in needs? * 1:32:56 - How does your team source equipment and talent for geothermal development? * 1:39:17- What is the most important problem that, if we could solve it today, would totally change things? 🎙 Why Geothermal, and Why Now? Tim explains how his journey into geothermal began with the Society of Petroleum Engineers (SPE) [https://www.spe.org/en/focus/geothermal/] and later deepened through Jamie Beard’s invitation to contribute to the Texas Geothermal Report [https://energy.utexas.edu/research/geothermal-texas]. His rigorous bottom-up modeling compared geothermal’s potential against IEA forecasts—and revealed the resource could, technically, meet a large amount of global energy demand by 2050. You can read the newest IEA report on Geothermal Energy here [https://www.iea.org/reports/the-future-of-geothermal-energy]. 🔢 How Do You Calculate Geothermal’s Potential? Tim walks through his methods—reservoir assumptions, gradients, power conversion models, and capital cost estimates. Initially, he assumed ~3–4 MW per well pair. But projects like Fervo’s at Utah FORGE [https://jpt.spe.org/fervo-and-forge-report-breakthrough-test-results-signaling-more-progress-for-enhanced-geothermal] have since shown yields closer to 10 MW, with the potential for much higher. ⚡️ Updating the Assumptions: From 3 MW to 25 MW+ What would Tim change today? Higher well yields, multiple laterals around a single injector, and innovations in pumping to boost flow rates. He sees pathways toward 25+ MW per “well unit,” crucial for serving hyperscaler data centers and other industrial loads. NREL has also published tools (read more here [https://www.nrel.gov/gis/geothermal] and here [https://www.nrel.gov/geothermal/data-tools]) that helped him through this process. 🛠 The Engineering Challenges of High-Temperature Wells We dig into hurdles like: * MWD tools frying at 175–200°C and solutions like mud cooling. * High-temperature cement integrity in projects like Iceland’s magma drilling. [https://www.sciencedirect.com/science/article/pii/S0375650518303523] * Fracture conductivity loss over time, requiring stronger proppants. 💻 Hackathons and Engaging Young Engineers Through SPE, Tim helped launch geothermal hackathons in Europe (newest one can be found here [https://www.spegeohackathon.com/]), blending data science and reservoir engineering. These programs brought students and young professionals worldwide into real geothermal problem-solving—creating a pipeline of new ideas and talent. 🏗 Lessons from Looking Globally Tim reflects on how the broader global market looks for Geothermal Energy: * Early assumptions about rapid rollouts were optimistic. * The US remains tough, given cheap natural gas. * Focus has shifted to regions with feed-in tariffs [https://en.wikipedia.org/wiki/Feed-in_tariff]/energy incentives (e.g., U.K.’s CfD [https://www.gov.uk/government/collections/contracts-for-differencehttps://www.gov.uk/government/collections/contracts-for-difference], Germany’s Renewables Energy Act [https://www.iea.org/policies/12392-germanys-renewables-energy-act], Taiwan’s FITs [https://www.moea.gov.tw/MNS/english/news/News.aspx?kind=6&menu_id=176&news_id=118710], Japan’s Feed in Tariffs [https://www.thinkgeoenergy.com/japans-government-pushing-geothermal-exploration-and-development/]), effectively promising higher prices energy producers an above-market price and long term certainty and demand to help derisk renewable energy investments. * Heat networks are a powerful way to deliver low-cost social benefits—and attract municipal partners. Check out our episode [https://geothermalweekly.substack.com/p/eric-bosworth-manager-of-clean-technology] with Eric Bosworth for more. 💧 Water, Reservoirs, and Creative Solutions Supplying enough water for fracking is a major challenge. Tim’s UK projects [http://geothermalwellsllc.com/index.html] explore options like: * Building reservoirs (a community amenity with biodiversity benefits). * Leveraging wastewater streams (e.g., from sewage treatment plants). * Exploring shallow aquifers for brine sources. * Developing and works with local partners (i.e. NHS working with Geothermal together for key parts of the geothermal project) 📈 Customers, Offtakers, and Market Discovery Who buys geothermal power and heat? * Electricity: utilities, microgrids, data centers, industrial plants. Can often provide these customers a hedge against fluctuating gas prices. * Heat: municipalities, district networks, hospitals, and industrial steam users (paper, cement, chemicals). * Challenge: geothermal wells produce more heat than most customers can use, requiring cascaded applications to capture full value (i.e. pairing a local producer who needs high heat with geothermal energy production, chaining high and low heat need customers to allow for multiple stakeholder geothermal projects, etc.) * Project Innerspace’s has also provided GeoMap [https://geomap.projectinnerspace.org/map-selection/] to help this process — It’s on open-access tool combining subsurface heat data with surface-level energy demand, helping developers spot promising project locations. * Opportunity: A new kind of player that could aggregate geothermal supply and route it to diverse customers (like pipeline companies do in oil & gas). 🌐 Incentives and Policy Lessons Outside the US, feed-in tariffs (see Lessons from Founding Geothermal Wells) and insurance products (i.e. Munich Re [https://www.munichre.com/en/solutions/for-industry-clients/unleash-the-potential-of-geothermal-energy.html]) de-risk early-stage projects. Tim stresses that faster permitting, long-term pricing certainty, and community trust are essential for scaling geothermal worldwide. 🚀 What Problem Would Change Everything? (Need’s Tim Review) Paraphrasing Tim’s words: If we could dramatically increase yield per well unit—from today’s 10 MW to 50–70 MW—that would change everything. * Higher yields mean fewer wells, faster buildouts, and the ability to serve massive loads like hyperscaler data centers competitively. * The lever: reduce parasitic losses in the reservoir — the friction and pressure drop when forcing water through fractures. * The vision: One injector with three producers could deliver ~55 MW net. A dozen such “well units” could power a 1 GW data center. 📚 Where to Learn More * Tim’s contributions to the [https://energy.utexas.edu/research/geothermal-texas]Texas Geothermal Report [https://energy.utexas.edu/research/geothermal-texas] * SPE’s [https://jpt.spe.org/]Journal of Petroleum Technology [https://jpt.spe.org/] * Mentioned Podcasts * Tim Tarver (Exceed GeoEnergy) [https://open.substack.com/pub/geothermalweekly/p/tim-tarver-founding-board-member?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] — Advanced geothermal drilling, fracking challenges, and water reuse. * Jen Wakeland (Beaver County, Utah) [https://open.substack.com/pub/geothermalweekly/p/jen-wakeland-strategic-development?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] — Community engagement, rural development, and transmission planning. * Bill Heins (Getech) [https://open.substack.com/pub/geothermalweekly/p/bill-heins-chief-geoscientist-of?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] — Insurance products and de-risking geothermal projects in Europe. * Eric Bosworth (Eversource) (Part 1 [https://open.substack.com/pub/geothermalweekly/p/part-1-eric-bosworth-manager-of-clean?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false], Part 2 [https://open.substack.com/pub/geothermalweekly/p/eric-bosworth-manager-of-clean-technology?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false]) — Utility-led networked geothermal and lessons from the Framingham pilot. * Ken Wisian (Bureau of Economic Geology, Texas) (Part 1 [https://open.substack.com/pub/geothermalweekly/p/part-1-ken-wisian-associate-director?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false], Part 2 [https://open.substack.com/pub/geothermalweekly/p/part-2-ken-wisian-associate-director?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false])— Military applications of geothermal and energy security. This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit geothermalweekly.substack.com [https://geothermalweekly.substack.com?utm_medium=podcast&utm_campaign=CTA_1]

Eric Bosworth - Manager of Clean Technology at Eversource [Part 2]

Hello folks, Welcome back to Part 2 of our conversation with Eric Bosworth (watch part 1 here [https://geothermalweekly.substack.com/p/part-1-eric-bosworth-manager-of-clean]). Eric is the Manager of Clean Technology at Eversource [https://www.eversource.com/content/business], his journey spanning oilfield engineering, utility infrastructure, and emerging decarbonization technologies. Currently, Eric leads efforts to pilot and scale alternatives to fossil gas [https://www.eversource.com/content/residential/about/sustainability/carbon-neutrality] - including hydrogen, carbon capture, and (most relevant) community-scale geothermal. He draws on field experience in oil and gas, system planning expertise from utility engineering, and a customer-first approach to identify and deploy the best-fit solutions across Eversource’s portfolio. Most notably, Eric led the development and execution of the Framingham geothermal pilot [https://www.eversource.com/content/residential/save-money-energy/clean-energy-options/geothermal-energy] - one of the first utility-owned thermal energy networks in the United States. 🧠 Highlights * Framingham's real-world data shows strong winter performance and customer satisfaction, even in extreme cold. * Scaling = viability: Networked geothermal shows falling marginal costs with larger customer bases. * Magic wand wish? Eric would create more drilling firms in the Northeast tomorrow; workforce gaps are the biggest blocker to scale. * Beyond boreholes: A future “thermal marketplace” could trade heat between buildings, pools, wastewater, and more. 🔍 Where to Learn More * Project updates & background: eversource.com/geothermal [https://www.eversource.com/geothermal] * Find Eric on LinkedIn to connect and collaborate * Industry groups: Heat pump alliances, geothermal networks, utility decarbonization forums This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit geothermalweekly.substack.com [https://geothermalweekly.substack.com?utm_medium=podcast&utm_campaign=CTA_1]

[Part 1] Eric Bosworth - Manager of Clean Technology at Eversource

Hi folks, We are back! This week, we’re bringing you part 1 of our conversation with Eric Bosworth [https://www.linkedin.com/in/ericbosworth/]! Eric is the Manager of Clean Technology at Eversource [https://www.eversource.com/content/business], his journey spanning oilfield engineering, utility infrastructure, and emerging decarbonization technologies. Currently, Eric leads efforts to pilot and scale alternatives to fossil gas [https://www.eversource.com/content/residential/about/sustainability/carbon-neutrality] - including hydrogen, carbon capture, and (most relevant) community-scale geothermal. He draws on field experience in oil and gas, system planning expertise from utility engineering, and a customer-first approach to identify and deploy the best-fit solutions across Eversource’s portfolio. Most notably, Eric led the development and execution of the Framingham geothermal pilot [https://www.eversource.com/content/residential/save-money-energy/clean-energy-options/geothermal-energy] - one of the first utility-owned thermal energy networks in the United States. 🧠 Highlights * Utility leadership in geothermal: Eversource demonstrates how utilities can leverage existing gas infrastructure expertise to deploy geothermal networks. * Framingham pilot as blueprint: A 140-customer, closed-loop system built within a mile-long loop highlights the viability of utility-owned thermal networks. * Permitting, community buy-in, and modeling: Success hinged on shallow bedrock, EJ-community alignment, and relentless community outreach paired with rigorous engineering modeling. 🔧 Eric’s Journey into Geothermal * Started as a field engineer with an international oilfield services company Schlumberger (now SLB) [https://www.slb.com/]. * Transitioned back to the U.S., worked on gas engineering at Eversource. * Volunteered for clean tech efforts, leading Eversource's geothermal pilot. * Past drilling experience proved invaluable for utility-scale geothermal deployment. 🏛 Role at Eversource: Clean Technology Strategy * Evaluates a suite of decarbonized solutions: geothermal, Renewable Natural Gas (RNG), hydrogen, carbon capture. * Applies a customer-centric framework to identify the right solution: * Geothermal fits for heating/cooling needs (residential, mixed-use, commercial). * Molecule-based solutions like hydrogen/RNG better suit high-heat industrial customers. 🧪 Inside the Framingham Geothermal Pilot * 140 customers across 36 buildings [https://www.eversource.com/content/residential/about/transmission-distribution/projects/massachusetts-projects/geothermal-pilot-project] in Framingham, MA. * Closed-loop system with 90 boreholes in a ~1-mile loop. * Launched via a 2019 [https://www.eversource.com/content/residential/save-money-energy/clean-energy-options/geothermal-energy/geothermal-pilot-reference-guide]gas rate case [https://www.eversource.com/content/residential/save-money-energy/clean-energy-options/geothermal-energy/geothermal-pilot-reference-guide] (a utility-regulator process to approve capital projects). Why Framingham? * Environmental Justice community - aligned with equity goals. * Shallow bedrock (~30 ft) - reduced casing costs and improved heat transfer. * Strong community partner - city support and diverse building mix (residential, commercial, housing authority). 📊 Site Selection + Modeling Process * Screening: Load mix, street space, depth to bedrock, customer interest. * Test boreholes post-selection to verify thermal properties. * Thermal network design: * Borehole spacing (20-25 ft) and placement modeled for loop stability. * Minimized thermal drift across customers in the network loop. * Tools used (via external Professional Engineering firm): * Borefield performance simulators * Transient energy modeling for pipes * Building load analysis 🏗 Construction & Bidding Execution Bidding Strategy: * Split into 3 scopes: * Drilling * Loop infrastructure (high density polyethylene (HDPE) pipe, mains, pump house) * Building conversion (heat pumps, ductwork, electrical) * Flexibility: Bidders could propose on full or partial scopes. * Winning bidder was a long-time gas pipeline contractor — installation process nearly identical to gas. Operations Notes: * Pipe used is standard HDPE, just black with “geothermal” instead of yellow gas striping. * General Contractor model used: prime contractor oversaw subcontractors for drilling, instrumentation, etc. 📣 Customer Outreach Strategy Challenges: * Knocking on doors as a utility = skepticism. Strategy: * Repurposed internal sales and marketing team to act as geothermal outreach reps. * Delivered: * Multilingual fact sheets, door hangers, community meetings and engagement [https://www.eversource.com/content/residential/save-money-energy/clean-energy-options/geothermal-energy/introduce-a-girl-to-engineering-science]. * Check out our podcast with Jen Wakeland [https://open.substack.com/pub/geothermalweekly/p/jen-wakeland-strategic-development?r=4nnexq&utm_campaign=post&utm_medium=web&showWelcomeOnShare=false] to learn more about how geothermal energy can engage well with local communities. * Hosted Q&As to build trust and clarity. * Leveraged city of Framingham [https://www.framinghamma.gov/3416/Geothermal-Pilot-Program] as a key ally for legitimacy and communication. * You can also see their website here [https://www.eversource.com/content/residential/save-money-energy/clean-energy-options/geothermal-energy]. 📝 Permitting in Massachusetts * Closed-loop geothermal = low regulatory friction. * Approval via city council and conservation commission. * No extensive state or environmental hurdles. * Easier than other states like NY, which previously required mining permits for deep drilling. 🛠 Lessons for Developers & Financiers * Utilities can deploy geothermal using existing gas pipeline teams - shared skillsets and tooling. * Shallow bedrock drastically reduces costs - site selection must prioritize geology. * Community trust must be earned - requires persistent, multi-channel communication. * Permitting varies widely by state - closed-loop systems often face fewer barriers. * Thermal network design is nontrivial - must model pipe loss, load variance, and peak conditions across time. Thank you so much for checking in and get ready for part 2 next Thursday! In the meantime remember to: And follow us on your favorite platforms in addition to sharing your thoughts, questions, and recommendations for future guests on: * Substack [https://geothermalweekly.substack.com/] * Spotify [https://open.spotify.com/show/15zmyZSCKGQMelbCjyEkBf] * Apple Music [https://podcasts.apple.com/us/podcast/the-geothermal-energy-podcast/id1801631361] * Amazon [https://music.amazon.com/es-co/podcasts/23b1877d-e32d-499d-9f4b-df6e862ab859/the-geothermal-energy-podcast] This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit geothermalweekly.substack.com [https://geothermalweekly.substack.com?utm_medium=podcast&utm_campaign=CTA_1]

Michael Brookman - Quaise Energy's Senior RF Engineer

In this episode, I sit down with Michael Brookman [https://www.linkedin.com/in/michael-brookman-33439950], a seasoned physicist whose career has spanned from nuclear fusion research to pioneering advancements in geothermal energy. Currently serving as a Senior Radio-Frequency (RF) Engineer at Quaise Energy [https://www.quaise.energy/], Michael focuses on leveraging RF technology to revolutionize geothermal energy production. Episode Highlights: * Michael's Journey: From his early days studying physics at the University of Wisconsin [https://plasma.wisc.edu/] to his pivotal roles in nuclear fusion projects across the U.S., including his tenure at General Atomics [https://www.ga.com/]and Commonwealth Fusion Systems [https://cfs.energy/]. * Transition to Geothermal: The motivations and insights that led Michael to shift from fusion to geothermal energy, emphasizing the potential for immediate impact, reduced cost, and scalability. * Innovative Drilling Techniques: An exploration of how Quaise Energy is adapting gyrotron technology—originally used in fusion reactors—to drill deep [https://www.quaise.energy/news/category/research]into the Earth's crust using millimeter waves, enabling access to superhot geothermal resources. * Overcoming Challenges: A discussion on the technical and regulatory hurdles in advancing geothermal technology and how Michael's team is addressing them. Join us as we delve into the intersection of fusion and geothermal technologies and discover how innovations in one field can catalyze breakthroughs in another. Thanks for reading The Geothermal Energy Newsletter! Subscribe for free to receive our new posts and podcast weekly! 🧭 Michael’s Journey: From Shotgun Accident to Fusion Physicist * Survived a childhood hunting accident, discovered fusion through video games like MechWarrior and Civilization. * Studied physics at University of Wisconsin (working on the Madison Symmetric Torus [https://wippl.wisc.edu/madison-symmetric-torus/]), then UT Austin for PhD (with Ken Gentle [https://physics.utexas.edu/directory/kenneth-gentle]’s group) * Specialized in RF systems and gyrotrons at General Atomics (working on their tokamak, DIII-D [https://www.ga.com/magnetic-fusion/diii-d]) and Commonwealth Fusion Systems [https://cfs.energy/]. 🔁 Why the Leap from Fusion to Geothermal? * Quase’s 2030 timeline is half that of fusion’s long timelines (2035+ [https://www.fusionindustryassociation.org/wp-content/uploads/2024/07/2024-annual-global-fusion-industry-report.pdf]). * Geothermal works now, and Quaise aims for <$75/MWh [https://www.quaise.energy/lcoe] vs. fusion’s projected $140–$500/MWh. [https://dspace.mit.edu/handle/1721.1/157003?show=full] * Inspired by How Big Things Get Done [https://www.amazon.com/How-Big-Things-Get-Done/dp/0593239512?crid=1RYXIWK8184Q5&dib=eyJ2IjoiMSJ9.IQVCFZCZpikj19Hb-qND1AvZ79U4R52GisH_HkUi2MuP92qC-Ljd_CaJq8alexr4lH5LLBmrdSJRIhkwLguB2s_tPeQTw-KaQUi1qQOHRdWga6pkOqtsh_yJFqS97pMcqRXjbV9EiDbOcuoELA-bluCcqIOJmwJwQLPtT43Z6vacUHIxvaQ0iG9braWlCc-9HQW3tTDA1A25YVnlAF3EGxQKEzzilFJlz5n7a1wGU_c.0D11n177JCrmj8cPO_INa2eIpNcitfw2nvOdfZ1_PKE&dib_tag=se&keywords=how+big+things+get+done&qid=1743978411&sprefix=how+big+things+get+done%2Caps%2C127&sr=8-1]—modularity is key to scaling - many gyrotrons making many wells. 💡 What is Quaise Doing? Goal: Unlock superhot geothermal by drilling with [https://www.quaise.energy/news/millimeter-wave-drilling-the-key-to-clean-energy-abundance]millimeter waves [https://www.quaise.energy/news/millimeter-wave-drilling-the-key-to-clean-energy-abundance]. The Tech: * Gyrotrons generate high-power millimeter waves that can drill through rock; basically they’re laser beams. * Current testing shows drilling to be at a rate of a meter per hour. * Power is transmitted through corrugated waveguides to vaporize rock—no conventional drill bits needed, avoiding typical wear and tear, bit trucking. * Uses compressed air to cool and clear debris from the hole. * See a video of the drilling in action here [https://www.quaise.energy/news/from-lab-to-field-testing]. Learn more about the research here [https://www.quaise.energy/news/category/research]. If you’ve read this far, you’ll like our future posts too : ) 🔬 Tech Challenges and Evolution * Managing arcing (essentially current hopping about the system in potentially damaging ways) in high-power systems (shutoff within 10 microseconds). * System resilience: Quaise’s protection systems and control software allow for long, stable runtimes—orders of magnitude longer than fusion pulses. * Powering the system: Needs ~3 MW input for 1 MW output (~40% efficiency). Can use diesel generators or grid, all containerized on trucks. * Manufacturing bottleneck: Gyrotrons are custom-built. Quaise works with Microwave Power Products [https://www.mppinc.com/] to scale production. ⚙️ Why Superhot Rock? * Electricity generated by heating water, putting it through a turbine, extracting power from the temperature & pressure drop - Higher input temperatures and lower output temperatures → higher thermodynamic efficiency * More energy per well = higher power density = more competitive with fossil and nuclear. 🧱 Barriers to Scale * Permitting takes 12+ months—slower than oil & gas (<12 months). * Goal: modernize geothermal permitting to match its competitors. 📈 What’s Next? * Near-term: Field deployment west of Austin, TX using 1 MW gyrotrons in truck-mounted systems. * Target: Delivering power in 5 years on the West Coast at scale; global expansion beyond that. * Long-term goals: * Scaling 1 MW gyrotrons (faster, deeper drilling) and drilling into hot basement rock (granite, basalt). * Lower cost per megawatt-hour to compete with all major energy sources ✨ Magic Wand Wish: Fix permitting. It’s the single biggest blocker to faster geothermal deployment. 📚 Learn More 🔗 https://www.quaise.energy Remember to: And follow us on your favorite platforms in addition to sharing your thoughts, questions, and recommendations for future guests on: * Substack [http://geothermalweekly.substack.com] * Spotify [https://open.spotify.com/show/15zmyZSCKGQMelbCjyEkBf] * Apple Music [https://podcasts.apple.com/us/podcast/the-geothermal-energy-podcast/id1801631361] * Amazon [https://music.amazon.com/podcasts/23b1877d-e32d-499d-9f4b-df6e862ab859/the-geothermal-energy-podcast] This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit geothermalweekly.substack.com [https://geothermalweekly.substack.com?utm_medium=podcast&utm_campaign=CTA_1]