Podcast-Take

Take on a podcast episode from Reviewer 2 does geoengineering, originally published Sat, 04 Ap. Listen: https://podcasters.spotify.com/pod/show/reviewer2geoengineering/episodes/Sustaera---electric-DAC-e3heke1 TL;DR Sustaera embeds Joule heating directly into a monolithic sorbent structure using a carbon-based resistor — no steam, no gas-phase heat transfer. Claims >90% heating efficiency in a 3.4L lab prototype. Sorbent is alkali carbonate on alumina, not amine: claimed 18,000–24,000 cycles (~3 years) before 30% degradation forces recoating. If real, that’s a meaningful operating-cost lever. Full adsorption/desorption cycle in 30–45 minutes; desorption at just 80°C, ramping in seconds. Host pushes back hard on whether this actually meshes with curtailed-power economics — worth hearing both sides. Manufacturing piggybacks on catalytic-converter production lines. Buried at the end of the episode, but arguably the most important claim. technology readiness level (TRL) 5 (1 t/yr indoor), raising $8.6M for a first 500–750 t/yr outdoor unit against $700/t pre-purchases from Stripe and Shopify. Andrew of Reviewer 2 Does Geoengineering interviews Corey Sanderson, CTO and co-founder of Sustaera, the North Carolina direct air capture (DAC) startup that spun out of incubator Sustion in 2021. It’s a proper technical grilling — sorbent chemistry, desorption physics, cycle economics — from a host who knows his physisorption from his chemisorption. Episode here. ...

Take on a podcast episode from Carbon Removal Newsroom, originally published Tue, 14 Ju. Listen: https://climateworkersanonymous.substack.com/p/4-the-denial-of-grief-plays-a-central TL;DR An anonymous submission argues for pausing all crediting of enhanced rock weathering (ERW) and ocean alkalinity enhancement (OAE) until end-to-end verification improves. Critical but fair. Core mechanism: open-system removals can’t be directly measured, so “phantom credits” used to offset real emissions pose both climate and reputational risk. Claims early findings already show actual removal well below estimates — no citations given, but directionally consistent with recent field-trial literature. Host Ross Kenyon explicitly frames all submissions as unverified. Treat this as practitioner-sentiment data, not evidence. The CDR-relevant content is roughly five minutes; the other two submissions (climate grief, virtue signaling) are off this beat. Episode #4 of Climate Workers Anonymous is Ross Kenyon’s anonymous-submission project: climate workers send in things they won’t say under their own name, and he reads them aloud. This episode carries three submissions, and one of them is a direct shot at the crediting of open-system carbon removal — which is why it’s worth flagging here despite the show’s soft format. ...

Take on a podcast episode from Reversing Climate Change, originally published Thu, 16 Ju. Listen: https://podcasters.spotify.com/pod/show/reversingclimatechange/episodes/408-The-impossible-taxonomy-of-carbon-dioxide-removal-e3m54kn TL;DR Solo episode: host Ross Kenyon reads his own Substack essay arguing that a “perfect” carbon-credit taxonomy wouldn’t meaningfully unblock climate action. Useful contrarian framing for a taxonomy-obsessed field. Core mechanism: categories like avoidance/removal/legacy fray at the edges immediately, yet practitioners communicate fine anyway — Wittgenstein’s “game” problem plus Polanyi’s tacit knowledge. His diagnosis: the real blockers are narrative and how humans handle the discount rate, not categorization gaps. Honest as a corrective, overstated where taxonomy is regulatory infrastructure. No guest, no numbers, no market data. This is a philosophy essay read aloud, not an episode you mine for figures. He explicitly doesn’t dismiss taxonomy work — “valuable work for some purposes” — he just demotes it from the critical path. Ross Kenyon goes solo on episode 408 of Reversing Climate Change, reading an essay he published on Substack, The Impossible Taxonomy of Carbon Dioxide Removal. No guest, no interview — just Kenyon working through whether the carbon dioxide removal (CDR) field’s endless categorization projects actually matter. ...

Take on a podcast episode from The CDR Policy Scoop, originally published Wed, 15 Ju. Listen: https://shows.acast.com/the-cdr-policy-scoop/episodes/inside-the-fight-to-save-600-million-for-dac-with-vikrum-aiy TL;DR Heirloom’s VP of policy explains how the ~$600M Louisiana DAC Hub award survived Trump-era review — while other hub tiers got cut. Useful post-mortem, not spin. Winning argument wasn’t climate: LNG export carbon intensity, workforce transferability, and hyperscaler siting. A repeatable playbook, candidly described. 45Q’s $180/t is intact post-BBB, but reporting is in limbo: EPA’s GHGRP move broke the verification chain, Treasury’s safe harbor lapsed end-2025, replacement framework not yet issued. California’s cap-and-trade extension put CDR integration into statute and lets emitters comply via direct capital expenditure (CapEx) investment into removal facilities — Aiyer sizes the market “in the billions.” The $85M/yr Cap-and-Invest pot is small; the statutory integration is the real story. First detailed practitioner account I’ve seen of the mechanism. Sebastian Manhart hosts Vikrum Aiyer, Heirloom’s head of global energy and climate policy, on The CDR Policy Scoop for a 30-minute tour of US direct air capture (DAC) policy: the DAC Hubs rescue, the 45Q reporting gap, and California’s Cap-and-Invest program. ...

Take on a podcast episode from Reviewer 2 does geoengineering, originally published Thu, 16 Ap. Listen: https://podcasters.spotify.com/pod/show/reviewer2geoengineering/episodes/Avantium-Engineering-Sorbents-for-DAC---Wessels-e3i16mo TL;DR Avantium sells high-throughput sorbent testing rigs (€350k–€1M) to DAC developers including Climeworks and Shell; 150+ units deployed, mostly for catalysis. Central claim: no standardized DAC sorbent test protocol exists — labs routinely publish one or two adsorption/desorption cycles as “results.” Plausible and underdiscussed. Wessels says early cycles show large variation, so single-cycle data is essentially noise. Real deployment means thousands of cycles. Avantium just joined the NIST Carbon Dioxide Removal consortium to push standardized breakthrough-curve protocols. Worth tracking. Claimed 4x reduction in sorbent time-to-market via 16-channel parallel testing. Vendor number, but customer-testimonial-backed. Andrew from Reviewer 2 does geoengineering interviews Rudolf Wessels, Director of Technology and Innovation at Avantium R&D Solutions, the Amsterdam-based Shell spin-out (founded 2000, publicly listed) better known for its plant-based PEF polymer. The DAC-relevant part: Avantium’s R&D Solutions unit builds parallel testing hardware that lets sorbent developers run identical adsorption/desorption experiments across multiple channels simultaneously. Episode here. ...

Take on a podcast episode from The Carbon Curve, originally published Thu, 25 Ju. Listen: https://carboncurve.substack.com/p/carbon-removal-is-not-one-thing TL;DR Counteract has screened 1,000+ CDR companies, invested in 27 — one of the widest dealflow vantage points in the sector. That alone justifies the listen. Core thesis: carbon removal is a category, not a pathway, so no single financing model fits — CREW’s small-ticket wastewater units vs. big DAC infrastructure need entirely different capital. Most striking claim: e-SAF costs $1,000+/t CO2 abated vs. $200–300/t durable removal, so aviation mandates should accommodate a removal share. Useful framing for policy fights. “Policy is expectation management” — the landfill tax analogy for how compliance signals unlock private capital. Not new, but well argued. Counteract is pivoting from early-stage venture to a “delivery fund” for first commercial projects. Worth watching who they raise it with. Na’im Merchant hosts Richard Barker, partner at Counteract, the 2021-vintage early-stage fund dedicated to carbon removal, on The Carbon Curve. The episode is an investor’s-eye tour of how capital actually flows into CDR (carbon dioxide removal) right now — pathway by pathway, with biomethane as the cautionary historical parallel. ...

Take on a podcast episode from The CDR Policy Scoop, originally published Mon, 06 Ju. Listen: https://shows.acast.com/the-cdr-policy-scoop/episodes/what-do-we-need-to-get-right-in-the-cdr-integration-into-the TL;DR The European Commission is reportedly leaning toward a public authority as intermediary for CDR procurement into the EU ETS — from public statements, not leaks. Significant if it survives co-decision. Carbon Gap’s position: integrate removals below the cap (“one in, one out”) for the first review period, revisit later. Hedges against mitigation deterrence. The “cap reaching zero” premise is shifting — Commission signaled in May that allowances will be issued well into the 2040s under a -90% by 2040 framing. Numbers to watch on 17 July: the 75 Mt central estimate for 2040 removals, a floated 100 Mt figure, and Carbon Gap’s ~21% of ETS emissions analysis. Only direct air carbon capture and storage (DACCS) and bio-CCS expected at launch; the mechanism for adding biochar and enhanced weathering matters more than the initial list. Useful framing. Eve Tamme hosts Louis Uzor (Policy Director) and Francesca Battersby (Associate Policy Lead) of Carbon Gap on The CDR Policy Scoop, recorded 6 July — eleven days before the Commission’s expected EU Emissions Trading System (ETS) review proposal. It’s a pre-game analysis of how carbon dioxide removal (CDR) gets wired into the world’s largest compliance carbon market. ...

Take on a podcast episode from The Land & Climate Podcast, originally published Fri, 26 Ju. Listen: https://www.landclimate.org/podcast/ TL;DR David Ho (Hawaiʻi, IPCC lead author) argues marine CDR isn’t ready — most techniques carry too many known unknowns to deploy. Fair and specific. Enthusiasm has cooled since ~2023 across CDR broadly, not just ocean. Matches what practitioners are seeing. Ocean iron fertilization: nutrient robbing effect only visible at scales we’ll never test. Models flag it, deployers dismiss it. Useful framing of the epistemic trap. Direct ocean removal is being added to IPCC methodology as a “political decision” despite research gaps. First time I’ve seen it stated this bluntly by a lead author. Governance gap: equilibration happens outside the deploying country’s EEZ — nobody’s worked out who claims the credit. Underrated issue. Bertie Harson-Bredinsky hosts David Ho of the University of Hawaiʻi at Mānoa, fresh off the 4th International Conference on Carbon Dioxide Removal in Milan and now a lead author on the IPCC methodology report covering CDR and CCUS. The conversation is a sober tour of marine CDR — iron fertilization, ocean alkalinity enhancement, direct ocean removal, and blue carbon — from someone who’s moved from cautiously curious to openly skeptical. Listen here: landclimate.org/podcast. ...

Take on a podcast episode from The CDR Policy Scoop, originally published Tue, 30 Ju. Listen: https://shows.acast.com/the-cdr-policy-scoop/episodes/iso-sbti-and-the-lcaw-verdict-on-corporate-net-zero-with-kay TL;DR ISO Net Zero draft + SBTi v2 launched same day at London Climate Action Week 2026; Axelsson worked on both, argues they’re complementary not competing. Big CDR concern: SBTi doesn’t require removals purchases before 2035 — Axelsson calls this a cost-based decision, not a science-based one. ISO does require 5-year removals milestones, which is stricter on near-term CDR procurement than SBTi. Useful distinction that hasn’t been widely surfaced. Alleged SBTi communication flaw: merged short + long-term standards may let companies claim “net zero aligned” with only a short-term target. Worth watching. Next fight: governance of commodity certificates (green steel, SAF, cement) — mass-balance and additionality risks echoing prior voluntary market failures. Sebastian Manhart and Eve Tamme host Kaya Axelsson of Oxford Net Zero one week after the simultaneous 22 June launch of the ISO Net Zero draft standard and SBTi Corporate Net Zero Standard v2. Axelsson worked inside both processes for three years, and the episode is essentially her post-mortem: what converged, what didn’t, and where the corporate demand signal for durable removals actually lands. ...

Take on a podcast episode from Reversing Climate Change, originally published Thu, 25 Ju. Listen: https://podcasters.spotify.com/pod/show/reversingclimatechange/episodes/405-Does-Managed-MRV-imply-the-existence-of-Unmanaged-MRV--w-Varsha-Ramesh-Walsh--Offstream-e3l8cev TL;DR Offstream is repositioning from a DMRV (digital monitoring, reporting, verification) software vendor to “Managed measurement, reporting, and verification (MRV)” — they do the work, not just provide a dashboard. Useful naming of an under-articulated category. Walsh’s claim: the head-of-MRV in-house hire is often more expensive than outsourcing the whole function. Plausible for small biomass developers, untested at scale. Most operational data in carbon projects still passes through a human at some point — bills of lading, odometer photos, clipboard entries. Honest admission worth hearing from a vendor. Thesis: every owner of a physical asset eventually becomes a carbon project developer. Big swing; light on the path to get there. Long surveillance-capitalism tangent eats ~20% of the runtime. Skippable. Ross Kenyon hosts Varsha Ramesh Walsh, cofounder/CEO of Offstream, on episode 405 to explain why Offstream stopped trying to be pure software and embraced what Walsh calls “Managed MRV” — a services-plus-platform model targeting biomass-based durable CDR developers (biochar, lumber mills with waste streams) and increasingly 48E ITC tax-credit work. ...