Thermal Storage and Demand-Side Flexibility: Inside the Tepeo Heat Battery

Send us Fan MailRelease Date: Heat Pump Week (UK)Host: Nathan Gambling (Beta Teach)Guests:Joe Sharp (Editor, Installer Online)Barry Sharp (Guild of Master Heat Engineers)Mark Denman (Guild of Master Heat Engineers)Michael Warring (Guild of Master Heat OverviewIn this special Heat Pump Week episode, host Nathan Gambling is joined by Joe Sharp from Installer Online and three expert members of the Guild of Master Heat Engineers. Recorded for the Installer Show and the Heat Pump Association (HPA), this episode addresses the top eight questions submitted and voted on by readers of the Beta Teach newsletter.Episode Q&A Summary 1. Do Large National Installation Companies Cause Issues for SMEs?The Consensus: Mostly yes initially, but market dynamics are shifting. Early on, some national players entered with rapid, low pricing that set unrealistic customer expectations. Regulatory fines for misinformation have since prompted market corrections.Local vs. National Impact: Independent installers note that homeowners often prefer a local engineer performing the survey rather than a corporate salesperson. National firms typically operate with a rigid "fit-in-the-box" mentality; when installations fall outside these parameters, they frequently refer leads back to local specialists.Market Outlook: The general agreement is that a rising tide lifts all boats, and business-size friction will naturally ease as demand scales.2. Are We Seeing Breakdowns with Heat Pumps Installed Less Than Five Years Ago?Reliability Findings: Core heat pump units are exceptionally reliable and robust. True component failures typically follow a standard "bathtub curve" (failing early due to manufacturing flaws or much later at end-of-life).Common Causes of Early System Issues: Problems arising within the first five years are almost universally tied to poor system design, incorrect commissioning, running systems at excessively high temperatures, or inadequate water quality management.Water Quality Standards: Guild engineers advocate rigorous chemical and hot flushing combined with demineralisation (using VDI units) rather than relying solely on chemical inhibitors. Guild Engineers regard Ricky from Thoroughflush as being the expert in helping engineers how to clean and keep heating systems from corroding. 3. What Are the Pitfalls in Underfloor Heating Design and Installation?The Design Gap: Underfloor heating (UFH) is seen as the gold standard emitter for heat pumps, but standard supplier designs often focus on selling pipe rather than tailoring layouts. Standard layouts default to uniform spacing (such as 150mm centres) without evaluating individual room heat losses or specific floor coverings.Overheating and Flooring Risks: Oversized heat outputs under sensitive floor coverings (like LVT) can cause flooring to delaminate or rooms to overheat. Proper design requires variable pipe spacing tailored to specific room loads.Zoning Strategy: Rather than using individual room thermostats to cycle zones on and off aggressively, control systems should manage maximum temperature thresholds to maintain steady system efficiency.4. What Would Encourage Guild Engineers to Do More Public Sector Work?Procurement Barriers: Public sector and local authority procurement frameworks remain heavily weighted on upfront capital cost rather than long-term system efficiency and whole-life value.Quality vs. Cost: Independent engineers find it difficult to compete under bureaucratic tender processes that prioritize the lowest bidder over engineered design quality, proper hydraulic balancing, and low-carbon performance.Administrative Burden: Strict Service Level Agreements (SLAs), severe penalties, and red tape mean that participating requires specialized corporate sizing and resources.5. How Might We Protect Low-Income Homes from Poor Installations?Performance Over Vanity: Guild engineers emphasize that focus should center on actual running cost per kilowatt-hour of heat generated rather than rigid Coefficient of Performance (COP) vanity figures.Proven Design: Ensuring every installation has a fully documented, provable design (heat loss calculations and correct emitter sizing) prevents poor setups.User Education: Case studies show identical systems in neighboring properties yield vastly different running costs, making post-installation homeowner education on operating heat pumps correctly just as vital as the hardware itself.6. What Are the Top Problems with Apprentices and Apprenticeships?Funding and College Structure: The current apprenticeship funding model heavily favors college structures rather than supporting small-business employers who deliver the primary hands-on training.Outdated Theory vs. Practice: Tutors are often disconnected from modern low-temperature heating techniques, and young apprentices are sometimes pushed into trades without sufficient foundational maturity.Operational Realities: Unlike trades where workers down tools sharply at 5:00 PM, plumbing and heating emergencies (like leaks or heating failures) often require staying on-site late, creating legal and logistical challenges for employing non-family apprentices.7. How Can the Consumer Information Gap Be Overcome?Consistent Messaging: The industry suffers from a noisy media landscape and contradictory advice. Trusted Repositories: Consumers should be guided away from rumors toward credible, expert-led platforms (such as specialised independent websites, community-run renewable hubs, and installer networks) that champion transparency and real-world performance data.8. Heat Loss Calculations: Using HTC Measurements vs. Room-by-Room DesignWhole-House HTC Limitations: While Heat Transfer Coefficient (HTC) measuring tools and sensors give a good high-level indication of whole-house heat loss, engineers note there can be a wide margin of error in practice.Why Room-by-Room Is Essential: Whole-house measurements cannot replace room-by-room calculations. Individual rooms vary significantly in external wall exposure, glazing, and heat loss parameters, making room-by-room design necessary to size radiators and pipework accurately.Episode Timestamps00:03 – Introduction to Heat Pump Week with Installer Online and the Guild of Master Heat Engineers.02:26 – Question 1: Do large national installation companies negatively impact SME installers?09:40 – Question 2: Reliability assessment and failure causes in heat pumps under five years old.19:29 – Question 3: Underfloor heating design pitfalls, pipe centres, and floor covering constraints.28:03 – Question 4: Public sector work incentives and procurement hurdles for independent heat engineers.33:20 – Question 5: Protecting low-income homes, running costs, and system monitoring.40:40 – Question 6: Challenges with plumbing apprenticeships, college funding, and trade working hours.52:14 – Question 7: Overcoming the consumer information gap and establishing consistent messaging.01:00:56 – Question 8: Heat Transfer Coefficient (HTC) measurement tools vs. room-by-room heat loss calculations.01:02:54 – Heat Pump Week wrap-up and closing sponsor acknowledgments.Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailEpisode OverviewIn this episode of BetaTalk, host Nathan Gambling sits down with Johan du Plessis, founder and CEO of Tepeo, to discuss the Zero Emission Boiler (ZEB) and the evolving landscape of UK heat decarbonisation. Johan shares his journey from oil and gas engineering and smart energy management at Ovo/Kaluza to developing a high-density ceramic heat battery that offers a plug-and-play alternative for homes looking to electrify. They dive deep into why flexibility and consumer choice are critical to achieving net zero, how heat batteries fit into the government's Warm Homes Plan and the Boiler Upgrade Scheme, and the role real-world empirical heat loss data plays in modern heating system design. Key Topics CoveredThe Origin of the ZEB: How smart energy aggregation and grid flexibility inspired a dry-core ceramic thermal store that mimics the installation simplicity of a gas boiler. Demand-Side Flexibility & Grid Integration: Harnessing half-hourly flexible tariffs to absorb excess renewable energy, lower heating costs, and alleviate grid curtailment. Policy & Subsidy Landscape: The inclusion of heat batteries in the Warm Homes Plan and the upcoming £2,500 Boiler Upgrade Scheme (BUS) grant. Thermal Storage vs. Chemical Batteries: Why high-temperature thermal storage offers a lower-cost, highly durable alternative without degradation over 20+ years. Bridging the Data & Policy Gap: Moving away from static EPC estimates toward measured heat loss coefficients to right-size domestic systems accurately. Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailOn the birthday of my late mum and the first anniversary of the Guild of Master Heat Engineers I have finally managed to get my cousin, Philip Gambling, on the podcast. He installed some of the first VRV/VRF systems in the UK. Joining him is another industry veteran Bob BeattieCheck it out and take a listen...it does get technical in partsSupport the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailIn this episode of BetaTalk, host Nathan welcomes heat pump expert Graham Hendra to discuss his latest project: an AI-driven platform called Energy Donkey, developed in collaboration with Planet Devices.Designed to replace frustrating online forums and standard LLMs that mix reliable and poor advice, Energy Donkey leverages a curated repository of verified engineering data and real-time operational metrics. The system functions across three distinct service levels:Free Homeowner Advice: Answers standard consumer questions regarding heat pump suitability, noise, and installation requirements using verified technical data.Direct Unit Control: Interfaces directly with heat pump hardware via a small monitoring device, allowing users to check operational statuses, schedule setback modes, set spending limits, and automate weather compensation using natural language prompts.24/7 Field Tech Support: Provides installers and engineers with instant, model-specific diagnostic rules and fault-code guidance around the clock, bypassing long manufacturer hold times.Operating on a freemium, pay-per-use credit model using "carrots," Energy Donkey reduces routine inquiry loads for manufacturers while offering real-time performance tracking, predictive maintenance alerts, and expert technical assistance.Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailIn this episode, Nathan speaks with Guild engineers Michael Waring (Bromley Energy) and Liam Knowles (The Heating People) about the daily realities of working on the tools in modern heating engineering. They move past surface-level talk to explore what it actually takes to run and grow a high-standard heating business today. Key discussion points include:The Recruitment Struggle: Why finding installers with the right work ethic, care, and attitude matters far more than baseline qualifications. Managing the Workload: How elite installers balance surveys, admin, and on-site labor using 30-minute triage calls and AI phone receptionists.MCS & Accreditation Realities: Navigating certification schemes, paperwork, and quality management systems as an established installer. Evolving Skills & Tech: Moving from gas boilers to heat pumps and air-to-air systems, tackling product shortages, and managing post-installation handovers. The Future of Training: Rethinking traditional college apprenticeships, on-the-job learning, and where manufacturer support needs to step up. An authentic look into the modern heating trade directly from those doing the work every day. Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailIn this episode I give a brief run down of what is currently happening in the sector. I discuss the recent Installer Show and how the Guild of Master Heat Engineers is attracting lots of attention and how many of the engineers are now offering Air to Air systems to their customers.  I also take a look at the competence person schemes (CPS) and the online boiler ordering business models. I then take a bit of a deep dive into the research around online assessment. Could we be jumping out of the frying pan into the fire?   Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailEpisode SummaryGuests: Zac Curtis (Innovation Lead for NextGen Home at E.ON) & Chris Bernkopf (CEO of Podero)How do you scale residential Energy as a Service (EaaS) without upfront capital? E.ON and Podero’s 18-home Midlands pilot demonstrates that combining automated zero-upfront multi-asset orchestration (heat pumps, solar PV, batteries, and EV chargers) into a single 10-year fixed tariff wrapper can achieve a +56 Net Promoter Score and stable household comfort. However, scaling this model to a broader target market of 680,000 homes depends entirely on overcoming physical installation bottlenecks, correcting widespread heat pump commissioning errors, and transitioning manufacturer software platforms from standalone thermodynamic efficiency (COP) toward predictive, time-of-use cost-curve steering.Technical Insights1. The Financial Architecture of Energy as a Service (EaaS)The core financial barrier to residential grid decarbonisation is the high upfront capital cost of low-carbon assets.The E.ON NextGen Home pilot addresses this by completely eliminating initial capital expenditure for the consumer. All hardware—including Vaillant heat pumps, SolarEdge solar arrays, and home batteries—is deployed at zero upfront cost.The asset capital paydown is amortised over a 10-year term and embedded directly into a stable, single monthly fixed tariff wrapper.To mitigate risk when a homeowner relocates during the contract term, the asset value is transferred to the property valuation. The incoming buyer inherits an optimised, low-operational-bill home with the initial capital pay-down effectively cleared through the house sale.Following the 18-home proof of concept, E.ON is planning a proactive call for entries to scale up to a representative sample of over 300 homes. This next phase will target specific home archetypes and a diverse mix of consumer behaviours to stress-test the model's mass-market viability.2. Multi-Asset Software Orchestration vs. Standalone COPTraditional heating controls are built to maximise standalone thermodynamic efficiency (COP).In modern dynamic, time-of-use energy systems where wholesale electricity pricing fluctuates sharply between midday and evening peaks, maximising standalone efficiency is an outdated metric.To generate true running-cost savings, Podero’s platform bypasses physical gateways to communicate via cloud APIs directly with the assets every few minutes.The software engine shifts focus toward predictive cost-curve steering by calculating the exact building energy deficits and the specific thermal deferral capacity (the duration a building envelope can safely delay or store heat load without dropping interior comfort).3. Supply Chain Quality and "Unconscious Incompetence"The deployment of automated multi-asset steering lives or dies on physical installation quality.A significant portion of the UK installation supply chain suffers from unconscious incompetence—well-meaning installers who lack the specific expertise required for low-carbon engineering.Common field errors, such as incorrect heat pump commissioning, frequently cause internal backup electric immersion heating rods to run continuously, driving up electricity consumption.Additionally, the transition of the UK heating industry into a fragmented landscape of self-employed sole traders complicates the rapid dissemination of best practices. Overcoming this requires a strict, synchronised "waterfall" installation process to handle complex asset interdependencies over a tight five-day window.4. Expanding Beyond Air-to-Water ArchetypesTo scale the EaaS framework past the initial pilot phase toward a representative market sample of 300+ homes, utilities must look beyond standard air-to-water heat pump systems.To accommodate tight mid-terraced houses and flats where external space or pipework disruption prevents traditional setups, the pilot is actively evaluating alternative low-carbon technologies.This includes compact, single-room heat pump configurations operating without external units, localised infrared matting, low-electricity radiant solutions, and smart electric boilers dedicated to domestic hot water (DHW) production.Industry Resources & LinksHost Profile: Nathan Gambling, Head of Technical Education at BetaTeach and host of the BetaTalk podcast. Referenced Data Expert: Mick Wall (Sheffield University), field data analyst tracking "The Holy Trinity" of integrated heat pump, battery, and solar performance telemetry. Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailOverviewIn this episode, we move beyond the industry’s obsession with nominal appliance ratings to confront a uncomfortable truth: "The Phantom Efficiency." We sit down with Robert Whitney to discuss why the UK heating sector is currently failing its first major test in the transition to electrification. We explore why we continue to chase theoretical efficiency gains on a spec sheet while ignoring the systemic failure of control strategies in the real world. This is a deep dive into the engineering reality of why our heating systems remain stuck in a high-temperature, on-off cycle, and why "effective control" is the missing link between a building’s design and its actual performance.Critical Discussion TopicsThe Myth of Nominal Efficiency: Why the sector prioritises the "sticker" efficiency of an appliance over the reality of how it operates within an integrated system.The "Lobotomised" Boiler: A technical deconstruction of why high-precision modulating boilers are being throttled by outdated switch-live logic, effectively stripping them of the very intelligence we paid for.Transition or Stagnation? Why the shift to heat pumps is exposing the industry’s deeper reliance on "rule of thumb" design. We discuss why the lack of systemic control knowledge is one of the greatest barriers to decarbonisation.The Path to Mastery:Why "lifelong learning" and peer-to-peer knowledge sharing—as championed by the BetaTeach ethos—are the only ways to move from phantom efficiency to verifiable performance.Key Technical TakeawaysBeyond the Appliance: Moving the industry narrative from "the boiler is efficient" to "the heating system is optimised."The Physics of Delta T: Robert clarifies why low-temperature flow are not just "nice to haves" but fundamental requirements for both condensing boilers and heat pumps.Data as the Antidote: How community-driven data initiatives (like OpenEnergyMonitor) are providing the hard evidence needed to challenge institutional inertia.About Our GuestRobert Whitney is an independent consultant and former technical leader in the global controls manufacturing sector. With a unique background spanning legacy controls and modern startups, he brings a "no-punches-pulled" perspective on the engineering realities of our current transition.ResourcesRead the latest newsletter: The Phantom Efficiency: Why Boiler Control Strategy Has Become the First Real TestOur thanks to the guild patrons for their continued support: CastRads, Primary Pro, UK Radiators, Payaca, Esby, and Woolsey's Renewables Centre.Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailRyan Jude of the Green Finance Institute (GFI) discusses how to mobilise capital for the UK's green home revolution.OverviewIn this episode, Nathan is joined by Ryan Jude, Programme Director at the Green Finance Institute (GFI) and former Cabinet Member for Climate in Westminster. While Nathan admits his expertise lies in the "weeds" of heat pump engineering rather than the world of high finance, the two find common ground in the necessity of making low-carbon technology the "rational economic choice" for the UK public.From the influence of legendary guitarists like Mark Knopfler and Dave Gilmour to the intricacies of Property Linked Finance (PLF), this conversation bridges the gap between technical installation and the financial mechanisms required to scale the UK’s transition to net zero.Property Background & The Financial ChallengeThe UK heating sector is currently at a crossroads. While the "want" for green upgrades is increasing due to volatile international energy markets, the "hassle factor" and upfront costs remains a significant barrier for the average homeowner.Ryan explains that "Green Finance" is not a separate entity, but rather a "tinge" on existing financial products—mortgages, unsecured loans, and infrastructure investments—designed to incentivise sustainable upgrades. The goal is a "Green Economy" where the distinction between green and traditional finance eventually disappears.Key Discussion Points & InnovationsThe Evolution of Green Mortgages: Since 2019, the market has expanded from just four niche products to over 93 today, with an estimated £14 billion annually now flowing through green mortgage products.Property Linked Finance (PLF): Ryan introduces the concept of lending against the land rather than the individual. Based on the "PACE" model in the US, PLF allows the debt to stay with the property, lowering risk for lenders and ensuring the liability passes to the next owner if the current resident moves.The "Hassle Factor" vs. Interest Rates: Evidence from Scotland suggests that a 0% interest rate isn't always the primary driver for consumers. Trust, ease of the customer journey, and the "hassle" of installation are equally critical in determining uptake.The Strategic Partnership: GFI is currently co-running a partnership with the government’s Warm Homes Plan, involving major high-street lenders like Barclays, NatWest, and HSBC to design accessible, low-interest, government-backed loans.Energy as an Asset: Discussion on how the National Energy System Operator (NESO) and demand flexibility schemes are turning heat pumps, solar PV, and batteries into assets that can actually reduce monthly outgoings through smart usage.Performance & EvidenceThe impact of current geopolitical events, such as the closure of the Strait of Hormuz, has led to a measurable surge in consumer demand.Solar PV: Requests to major suppliers like Octopus and EDF have increased by over 50%.Electric Vehicles: EV demand has mirrored this uptick, as the cost-per-mile (approx. 8p at home vs. 18p at the pump) makes them the cheaper long-term choice.Scale: Over 27,000 solar installations were recorded in March 2026 alone—the highest in over a decade.Closing ReflectionThe transition to a low-carbon home is no longer just a moral choice; it is becoming a financial necessity. As Ryan notes, success will be achieved when the average consumer wakes up wanting the technology not because it is "green," but because it is the smartest way to protect their household from global energy volatility.Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky

Send us Fan MailThe UK heat pump sector is entering a new phase. In this episode, we speak with senior leaders from the newly formed Association, created by merging three major industry bodies (Ground Sorce Heat Pump Association, Heat Pump Federation and Heat Pump Association) into a single, unified voice: The Heat Pump Association UKWe explore why this merger happened, what it means for installers, manufacturers, and homeowners, and whether heat pumps are finally ready to scale across the UK. From policy challenges to consumer misconceptions, this conversation breaks down the real barriers in the race to decarbonise heating.Support the showLearn more about heat pump heating by followingNathan on Linkedin, Twitter and BlueSky