> ## Content Index > Fetch the complete content index at: https://nexi.fund/llms.txt > Use this file to discover other available public pages before exploring further. # NOX Energy raised €3M to trade household heat pumps like a currency - URL: https://nexi.fund/nox-energy-heat-pump-flexibility/ - Published: 2026-10-03T10:30:53.000Z - Updated: 2026-10-03T10:30:53.000Z - Description: NOX Energy earns $72k ARR from a megawatt of commercial heat-pump flexibility and $72 a year from a house. The Antwerp startup closed a €3M seed round to build the software layer that turns heat pumps already in people's cellars into participants in wholesale power markets. - Author: Nexi.fund Labs - Tags: Energy & Climate, #mode-2, #hook-statistic, #track-E NOX Energy earns $72,000 a year from a megawatt of commercial heat-pump flexibility and $72 a year from a house. That 1,000x gap is the business model. It is also the reason nobody has built this market at scale. The Antwerp startup closed a €3M seed round on 30 September, co-led by Rise PropTech and Volve Capital, with Seeder Fund joining. It wants to be the SWIFT of energy flexibility — the settlement layer that lets a heat pump be bought and sold on wholesale power markets. The company says it has connected more than 10,000 devices. Rival Axle Energy claims 300,000. Neither number settles the question that matters. A connected heat pump is inventory. A paid one is a product. ## A small round for a large category The round follows a $1M seed from December 2024, which came out of the Entrepreneurs Roundtable Accelerator in New York. NOX Energy was registered in Belgium in 2024 and now runs about 16 people, up from 11 in March. Founded by Axelle Moortgat, 26, Louis Clermont, 24, and Martin Michaux, it sells two products from the same software layer: a white-label platform for heat-pump manufacturers, and an API that lets utilities and aggregators bid the resulting flexibility into day-ahead, imbalance, automatic frequency restoration (aFRR) and capacity markets. No hardware, no installer, nothing mounted on the wall. A heat pump already in someone's cellar becomes a market participant through a cloud-to-cloud connection. ## Where the revenue actually is $72k ARR per MW (commercial) #### Commercial heat-pump flexibility What NOX Energy reports earning per megawatt of commercial capacity. The residential figure in its own materials is $72 a year. · *NOX Energy company deck* The company's investor materials put the asymmetry in plain numbers. A megawatt of commercial flexibility carries $72,000 in annual recurring revenue. A residential household carries $72\. The deck also shows a $241k per MW figure and a $7,000–$30,000 recurring band for commercial buildings, without labelling precisely what each one measures. | Parameter | Commercial building | Residential household | | ------------------------------ | --------------------------------------------------- | ------------------------------------- | | **Recurring revenue per unit** | ✔ $72k per MW | ✗ $72 per year | | **Onboarding** | Building management system, cloud-to-cloud | App only — no hardware, no installer | | **Products sold into** | Day-ahead, imbalance, aFRM, capacity | Dynamic tariffs, self-consumption | | **Revenue the company names** | Income from heat-pump dispatch on imbalance markets | Cashback rewards for enrolled devices | Company-reported figures, NOX Energy investor materials, 2026 One megawatt of commercial capacity is a building with a building management system, a portfolio large enough to matter to an energy supplier, and a controller that can be trusted to hold a setpoint for the length of an imbalance auction. One house has none of those things. It has a compressor, a consumer who notices when the living room is cold, and a market that pays roughly the price of a coffee a month for the privilege. The pitch works anyway, because the volume is on the other side of the ledger. NOX Energy names 1.5M heat pumps connected to the cloud in its pilot pipeline, against the US and European installed base its own deck puts at 25M units in 2020 and 60M by 2026\. One fortieth of that installed base is worth 1,000x more than a household — so the margin per megawatt and the number of megawatts are the same argument, and the company has not said which side it is betting on. ## The supplier problem came first Moortgat's previous company let Belgian households sell surplus solar power to their neighbours. Energy suppliers did not like it. They pay penalties when their portfolios fall out of balance, and a neighbourhood marketplace moved load around without their consent or their settlement. Her next idea worked with those suppliers instead, she told Forbes Belgium. Read that history into the product and the round size, and a €3M seed for a 16-person company looks like a bet that the market rules arrive before the runway does. Demand response on the grid is not new territory here. In September we covered \[Emerald AI and the demand-response grid\](/emerald-ai-demand-response-grid-2026/). Residential flexibility is the harder version of the same problem, and the €72 line is what it costs to solve it badly. ⚠️ **Every number above depends on a market rule, not on the heat pump** Imbalance, aFRR and capacity markets have to exist, stay open to residential assets, and pay enough to clear a €72 line. NOX already sells into the aggregator side of those products. The household line is the one waiting on a rule change. The engineering is the easy half. Axelle Moortgat is selling a SWIFT for a currency that European market designers have not issued. That is a harder pitch than a battery, and a more valuable one if the rules arrive. The €3M buys time against that possibility. [ NOX Energy raises €3M to become the SWIFT of energy flexibility The round, the co-leads, the founders' ages and the 10,000-device claim against Axle Energy's 300,000 — plus the account of the first company the suppliers rejected. Tech Funding News, 30 September 2026 ](https://techfundingnews.com/nox-energy-raises-e3m-to-become-the-swift-of-energy-flexibility-for-europes-homes/?ref=nexi.fund) The only trade-press writeup with the founders' own account of why the first attempt failed. Everything about the supplier-penalty problem comes from here. [ Belgian energy software startup NOX Energy raises €3 million seed Independent confirmation of the amount and the co-lead structure, and the clearest statement of the scale-to-Europe intent. Startup.eu, September 2026 ](https://www.startup.eu/investments/nox-energy-3-m-seed-09-2026?ref=nexi.fund) Used to confirm the round independently rather than relying on a single trade outlet for the financial figure. [ Residential flexibility as a revenue engine — the utility pitch Where the $72k and $72 figures come from, along with the day-ahead, imbalance, aFRM and capacity market products and the negative-price revenue line. NOX Energy company materials, 2026 ](https://www.nox.energy/solution/utilities?ref=nexi.fund) A company source, so every unit-economics number is attributed as company-reported. The unit line is the spine of this piece and nothing else states it.