Deep Tech Brief #08

Welcome to this week's issue of Deep Tech Brief.

Every Saturday, we break down deep tech companies building genuinely hard things, in plain language. No jargon, no hype.

Three companies this week: fibre recycling in Sweden, laser drilling in Munich, a lab-free cancer test in Leipzig.

Let’s dive in.

Europe throws away more than 12 million tonnes of textiles a year and under 1% comes back as new fibre. That gap is not for lack of trying. It is what modern clothes are made of.

Look at the label on almost anything you own and you will find a blend, usually cotton mixed with polyester, plus dyes and finishing treatments. Mechanical recycling shreds fabric, shortening the fibres and giving you something weaker than what went in. Chemical recycling dissolves the plastic back into its building blocks, which works but is energy-hungry and needs one clean material. Blends defeat both, and blends are what people wear.

Renasens, founded in Stockholm in 2022, separates them with carbon dioxide. Squeeze CO2 hard enough and it behaves partly like a liquid and partly like a gas, moving through fabric like a solvent and carrying things out with it. Renasens does this in two steps: strip out the dyes, then separate the fibres. The cotton and polyester come out whole rather than broken into chemicals, so they go straight into existing spinning equipment. No water, no toxic solvents, no new machinery for the customer. Founder Dr Jade Bouledjouidja describes it as renovating a house rather than demolishing it.

The idea came from an unrelated field: her PhD at Aix-Marseille used the same fluids to push drugs into polymers, and she saw the physics would also pull dye out of a t-shirt. She validated it at KTH Royal Institute of Technology.

Where they are: a €10 million seed in March led by Extantia, with Course Corrected VC and existing backer Norrsken Launcher, reported as the largest hardware seed round in Europe this year. It is building a pilot plant in Borås, machinery arriving through the second half of this year, and says it already supplies recovered cotton and polyester to manufacturers in Portugal and Italy. It also won the H&M Foundation's Global Change Award in 2025.

Worth watching, because the timing is unusually good. Separate textile collection became mandatory across the EU in 2025 and producer responsibility rules arrive by 2027, so brands will soon be paying for exactly this. The test ahead is the one every materials company faces: Borås has to show the economics hold at industrial volume, not just that the chemistry works.

Learn more: renasens.com

Europe imports more than 90% of its critical minerals and around 58% of its energy. Both numbers have become uncomfortable, and the EU now wants a tenth of its critical raw materials mined at home by 2030.

The awkward part is that the material is already here, along with enormous geothermal heat sitting in hot rock a few kilometres down almost anywhere on the continent. The reason neither gets used is drilling. It is the largest single cost in both mining and geothermal, and it gets sharply more expensive the deeper and harder the rock, because a mechanical bit grinding through granite wears out and has to be hauled to the surface to be replaced.

Hades, founded in Munich in 2025, never touches the rock. It sends a high-power laser down a fibre to the bottom of the hole, superheats the rock until it fractures, and clears the debris with high-pressure gas in milliseconds. Nothing grinds, so nothing wears out. In the lab the company reports 30 to 50 metres an hour through granite at a 21-centimetre borehole, and delivery of over 80% of its laser power across 10 kilometres of fibre.

The strategic choice is as interesting as the physics. Hades is not selling drills. It holds the licences, drills itself, and sells the output: tonnes of minerals now, geothermal heat later. Harder to build, but the gains accrue to Hades rather than to a customer.

For a sense of timescale, the closest comparison is Quaise Energy in Massachusetts, working on a related idea with microwaves since 2018 and expecting its first plant around 2030. A decade-scale category.

Where they are: €15 million in February co-led by HV Capital and Headline at a reported €67.5 million valuation, on top of a €5.5 million pre-seed, taking the total past €20 million inside a year. The founders are Dr Max Werner, Björn Dressler, formerly chief operating officer at Isar Aerospace, and Dan Gengenbach, previously at Marvel Fusion. The team has separately tested rock destruction, borehole clearing and 200 kilowatts of power delivery, and is growing from 11 people toward 36.

One to watch. The problem is about as strategically important as European industry gets, and the founders have built hard hardware before. The milestone that matters is the move out of the lab: proving those granite numbers in a real borehole at depth, on the way to a first operating site targeted for 2029.

Learn more: hades.com

Cervical cancer kills roughly 350,000 women a year and is among the most preventable cancers there is. The obstacle is not medicine. It is plumbing.

Almost every case is caused by HPV, a virus detectable years before cancer develops. The reliable way to find it is a PCR test, which needs a laboratory: trained staff, a machine that heats and cools the sample repeatedly, refrigerated chemicals, mains electricity. Around 85% of deaths happen in countries short of those labs, and average screening coverage across sub-Saharan Africa is about 4%. The World Health Organization wants 70% of women screened twice by 2030. That arithmetic does not work on today's infrastructure.

Intu Diagnostics, a spin-off from the Fraunhofer Institute for Cell Therapy and Immunology in Leipzig, has put the whole test inside one sealed cartridge. Collect a sample, drop it in, and 30 minutes later it changes colour. No reader, no app, no power supply, no training.

What it looks for is the distinction that matters. Rapid antigen tests, the kind everyone used during covid, detect proteins. They are quick, cheap and they miss a lot of infections. Intu's cartridge goes after genetic material, the same target as lab PCR, so it should be considerably more sensitive than the tests it would replace. Running that chemistry with no machine and no electricity is the clever part, and the company is keeping those details to itself for now.

Where they are: founded in 2023 by Dr Skaiste Arbaciauskaite and Dr Dirk Kuhlmeier, with just over €3 million raised after a €1.1 million bridge round in June backed by BSV Ventures and Saxony's development bank. A Fraunhofer-coordinated project is running proof-of-concept work with clinical samples from Leipzig University Hospital's gynaecology clinic. Launch is targeted for 2027, and the same cartridge is aimed at respiratory viruses, malaria and tuberculosis.

One to watch, carefully. If a cartridge this simple performs like lab PCR in the field, it removes the largest single barrier to a global health target, and the platform points at several more diseases. The open questions are the ones every diagnostic answers in order: published accuracy data, then regulatory approval, then a price that works where the test is meant to go.

Learn more: intudiagnostics.com

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See you next Saturday.