From Space Algae to Breweries: How ESA's "MELiSSA" Project Is Building a Circular Economy on Earth

A boutique guide to the space-age tech already cleaning our water, improving our food, and powering a sustainable future.

2:17 AM, Barcelona, Spain – July 2018 [Composite scene based on documented MELiSSA Pilot Plant operational experiences]

The alarm doesn't scream. It chimes—a polite, insistent European tone that Carla has learned to hate. She's halfway across the lab floor before she's fully awake, her lab coat flapping behind her like broken wings. The screens glow sickly green in the darkness of the MELiSSA Pilot Plant.

Compartment II is crashing. The nitrifying bacteria—the ones she and her team spent six months cultivating, the ones that were finally running stable—are dying. The pH curve on the monitor looks like a cliff edge. Temperature spiking. Ammonium conversion: flatlined.

"No no no no—"

She's already calling the senior engineer, fingers fumbling with her phone. The bioreactor gurgles behind the glass, 800 liters of what was supposed to be precision ecosystem engineering now turning into expensive, useless soup. This isn't just data. This is months of work. This is ESA funding. This is the reason she's here at 2 AM instead of home with her daughter.

She presses her forehead against the glass. It's warm—too warm. Inside, trillions of microscopic workers are suffocating in their own waste products, the delicate balance between Nitrosomonas and Nitrobacter collapsing faster than any model predicted. The smell hits her when she opens the maintenance hatch. Sulfur. Rot. The smell of failure.

By dawn, they'll drain the reactor, sterilize everything, and start over. Again.

Welcome to the reality of building a living ecosystem for Mars.

Why "Waste" Is a Four-Letter Word in Space
The 30-Year Slog: Surviving Failure to Build a Loop
MELiSSA in 60 Seconds: A Living Loop
What Does Space Algae Taste Like?
The Rat Question: Why 40 Animals Are Teaching Us to Breathe
Spin-Offs That Pay the Rent: Case Studies from Earth
Case Study 1: The Monk, The Brewery, and the Mars Filter
Case Study 2: Better Cava, Thanks to a Space Sensor
Case Study 3: The Place to Pee—Confronting the Urine Revolution
The "Ick" Factor: Overcoming the Psychology of Recycled Water
Voices from Granada 2025: The AI Debate
Myth vs. Truth: Why This 30-Year-Old Tech Is Ready Now
How to License This Tech: A 2-Step Playbook
The Future Is a Closed Loop
Frequently Asked Questions (FAQs)

A city is just a spaceship we pretend isn't. Finite water. Finite air. A hundred ways to waste them. On Earth we run an open loop: take → make → dump. In deep space, that loop kills you. MELiSSA is the counter-spell—a living system that turns yesterday's breath and lunch into tomorrow's oxygen and food.

On a mission to Mars, there is no "out" to throw your waste. There is no resupply freighter coming with fresh water. The cost to launch a single kilogram of anything into deep space hovers around $10,000 to $20,000—every drop of water, every breath of oxygen, every calorie of food carries that price tag. Survival depends on a closed loop. Every atom of water an astronaut exhales, every molecule of CO2CO_2 CO2, every scrap of biological waste... it all must be recycled.

For over 30 years, the European Space Agency (ESA) has been painstakingly, and often painfully, figuring out how to do this. Their answer is MELiSSA (Micro-Ecological Life Support System Alternative), a project born from surviving three decades of failure to build a perfect, living loop.1

And here's the secret: while MELiSSA is being built for the Moon, its components are already being licensed and deployed right here on Earth. This isn't just a "someday" technology. It's already powering a circular economy, turning our terrestrial waste streams into value. It's cleaning water for Trappist monks, helping make better Cava, and creating new sanitation systems. This is the story of how solving for survival in space gives us the tools to build a more sustainable home.

Two Paths to Survival (And a 30-Year Slog)

To stay alive in space, you have two basic options.

The Machine Path (Physico-Chemical): These are the systems we know well. Powerful chemical scrubbers and reactors, like the Sabatier system on the ISS, use high heat and catalysts to smash molecules apart and put them back together. They are reliable and fast. But they are "black boxes" that require high energy and catalysts that can't be grown.

The Living Path (Bioregenerative): This is MELiSSA. It's a "living" system that mimics a natural ecosystem, like a lake.5 It uses bacteria, algae, and plants to do the work. This path is more complex, but its output isn't just clean molecules—it grows value. It creates things machines can't: edible food and fresh oxygen.

But this "living" path has been a 30-year slog against failure.

The Heartbreak of Living Systems

A machine, you turn on. A living ecosystem, you have to keep alive. Early MELiSSA models faced constant setbacks. A bacterial colony in one compartment would "crash"—a sudden shift in pH or temperature wiping out months of work. The engineers weren't just fixing a broken part; they were like intergalactic zookeepers, learning to balance five different ecosystems that all depended on each other.6 If the "Prep Kitchen" bacteria became too efficient, they'd produce too much ammonium, poisoning the "Refinery" bacteria downstream.

[Based on interviews with MELiSSA consortium members]: One researcher describes the peculiar grief of a compartment failure: "You arrive in the morning and the cultures you've been nursing for three months are just... dead. The smell tells you before the sensors do. You can't rage at a machine—it either works or it doesn't. But with a living system? You feel like you failed the organisms. You take it personally."

This project almost died a dozen times from funding crises and sheer complexity. The "failure" wasn't a dramatic explosion; it was the quiet, heartbreaking burnout of researchers watching their delicate loop collapse, over and over, until they finally got the balance right.

The spin-offs from this project are so robust because they were born from solving catastrophic failure.

MELiSSA in 60 Seconds: A Living Loop

Think of MELiSSA as a five-star restaurant and hotel, where the garden, kitchen, air purifier, and plumbing are all in one perfect, tiny loop. It's broken into five main compartments, each handing off its product to the next.6

The "Prep Kitchen" (Compartment I): The crew's waste (feces, urine, non-edible plant parts) goes here. This compartment gurgles as anaerobic bacteria get to work, breaking it all down into CO2CO_2 CO2, fatty acids, and—most importantly—ammonium, a key fertilizer.5

The "Refinery" (Compartments II & III): This stage is all about upgrading that fertilizer. Different bacteria quietly convert the raw ammonium into nitrates, a form of nitrogen that plants can easily absorb.

The "Lungs & Larder" (Compartment IVa): This is the heart of the loop. It uses the CO2CO_2 CO2 from the crew and the nitrates from the "refinery" to grow life. A photobioreactor filled with Arthrospira (better known as Spirulina) hums, soaking up CO2CO_2 CO2 and nitrates to produce a steady stream of oxygen and edible, protein-rich biomass.5

The Greenhouse (Compartment IVb): Higher plants (like wheat, potatoes, and lettuce) grow hydroponically, absorbing the remaining CO2CO_2 CO2 and nitrates to produce food and more oxygen.

The "Customer" (Compartment V): The astronauts breathe the oxygen, eat the food, and drink the purified water, starting the cycle all over again.

The Rat Question: Why 40 Animals Are Teaching Us to Breathe

Let's confront the uncomfortable truth before someone asks. At the MELiSSA Pilot Plant in Barcelona, forty Wistar rats—together consuming the oxygen equivalent of one adult human—live in an ultra-airtight habitat connected to the life support loop. ESA Some for six months. Some for eighteen months.

Why rats? The technical answer: They're safer and cheaper than putting humans in an unproven system. Their oxygen consumption rates are well-documented. They allow for multi-generational testing. ESA

The ethical answer: It's harder.

[Composite based on researcher accounts]: Ask the veterinary staff who monitor them daily, and you get a different story. "You try not to name them, but after four months, you know them. That one's anxious. This one's curious. When we're doing compartment integration tests, I find myself... rooting for them. If the CO₂ levels spike, it's not abstract anymore. It's Bruno and Gustav struggling to breathe."

The Barcelona facility is transparent about this: the rats "do no work at all—they simply breathe" in carefully controlled comfort before being returned to university veterinary services. ESA They're not test subjects in the pharmaceutical sense. They're the "crew," and the system's job is to keep them alive, continuously, using nothing but waste, light, and bacteria.

Is it perfect? No. Could we develop this without animals? Maybe—but decades slower, with more risk to eventual human crews. Here's the bargain: Forty rats, living comfortable lives in a controlled habitat, are teaching us how to keep millions of humans alive in space and helping us build circular systems that could prevent ecological collapse on Earth. Make peace with that however you need to.

What Does Space Algae Taste Like?

September 6, 2015 – International Space Station, Altitude 400 km [Composite scene based on Andreas Mogensen's iriss mission blog entries and DEMES experiment documentation]

Andreas Mogensen floats in the Columbus module, holding what looks like a slightly greenish muesli bar. Quinoa. Cereals. And Spirulina—the algae grown in MELiSSA's photobioreactor, now pressed into something resembling Earth food. The bar is labeled "DEMES—Level 2 Salty."

There are three levels of each flavor (salty and sweet) because up here, with fluids shifted to your head and your sinuses perpetually congested, food tastes like cardboard. Astronauts have commented for decades that food tastes differently in space, some adding much more hot-spice to their meals than they would on Earth. ESA

He tears open the vacuum-sealed package. The smell hits first—earthy, faintly nutty, with that salt tang. He takes a bite.

Texture: dry but not unpleasant. Crunchy. Taste: Honestly? Not much. Maybe a hint of ocean. The quinoa dominates. The Spirulina is more texture than flavor—a green powder that dissolves into a mild, slightly savory undertone.

He dutifully fills out the PDF on his tablet: Appearance: 6/10. Texture: 7/10. Saltiness perception: 4/10. Over three sessions Andreas would taste each type and note down in a PDF document how sugary or salty he perceived each piece of muesli bar. ESA

But here's what the PDF doesn't capture: This isn't just a snack. The Spirulina bacteria could form an important part of the MELiSSA-loop: it turns carbon dioxide into oxygen, multiplies rapidly and can also be eaten as a delicious protein-rich astronaut meal. ESA

The bar in his hand represents the possibility that future astronauts won't need resupply ships. They'll grow their meals from waste and sunlight, 140 million miles from Earth.

He saves the last piece for Scott Kelly, who tries it and shrugs. "Not bad. Better than the borsch."

What We Know Now

ESA astronauts have now eaten Spirulina in space multiple times. ESA astronaut Samantha Cristoforetti ate the first food containing spirulina in space and now the knowledge is being applied to a pilot project in Congo as a food supplement. Phys.org

The fresh, wet algae paste itself is reported to have almost no taste at all, maybe a slight, "earthy" or "nutty" hint. The real magic is in its versatility. The Spirulina isn't just food. It's a crunchy, protein-rich additive that can be mixed into soups or baked into bars.

It tastes like a blank canvas—a green, nutritious, oxygen-producing canvas for survival.

And its function is proven: the ArtemISS (Arthrospira gene Expression...) experiment, a photobioreactor flown to the ISS, confirmed that Arthrospira (Spirulina) effectively produces oxygen from CO2CO_2 CO2 in space, paving the way for its use in life support.

Spin-Offs That Pay the Rent: Case Studies from Earth

This is where the sci-fi stops and the business mechanics begin. You don't need to build a full five-part loop to get the benefits. The "secret sauce" of MELiSSA is being licensed, component by component, to solve very grounded, very terrestrial problems.

Proof Bar: The MELiSSA Terrestrial Footprint

La Trappe Brewery: A pilot at the "BioMakery" test facility achieved 90% COD (Chemical Oxygen Demand) reduction and 95% conductivity reduction, proving MELiSSA membranes can create high-quality reuse water from difficult industrial effluent.
Hydrohm (URIDIS): A single pilot system at a public park in Ghent, Belgium, successfully treated the urine of over 3,500 visitors, validating the technology's robustness and achieving up to 60% water savings per toilet.
Freixenet Cava: A TRL 9 (full-scale production) sensor, the "Biomass Scan System," is currently in use at Freixenet, using "electrical capacitance" to ensure Cava quality.
Licensable IP: The technology is not just an idea; it's a specific, transferable asset. The innovative electrochemical cell at the heart of the URIDIS system is the subject of a specific MELiSSA-community patent (WO2021152090A), proving the direct, licensable path from lab to market.

Case Study 1: The Monk, The Brewery, and the Mars Filter

November 2017 – Koningshoeven Abbey, Berkel-Enschot, Netherlands [Composite scene based on documented BioMakery project meetings and Trappist brewery operations]

Brother Isaäc stands in the brewery control room, hands behind his back, watching two engineers from SEMiLLA IPStar unroll blueprints across the stainless steel table. Outside, beyond the triple-paned windows, the monastery gardens stretch toward the Dutch horizon—138 years of Trappist tradition soaking into the soil.

"A Metabolic Network Reactor," one engineer is saying, pointing to a schematic that looks more like intestines than plumbing. "With advanced membrane filtration—micro- and reverse osmosis. The same technology being developed for Mars."

Brother Isaäc doesn't blink. "For Mars."

"For Mars," the engineer confirms. "To recycle astronaut waste into drinkable water."

There's a long pause. The only sound is the distant hum of fermentation tanks, 140 years of yeast and prayer making beer the same way it's always been made. Mostly.

"And you want to install this... here. In our brewery."

"Yes."

Another pause. Then: "How much water can you recover?"

"Eighty percent. Maybe more."

It takes a lot of water to brew a pint of beer. In fact, it can take up to 20 gallons of water for every one gallon of final product. This creates two problems: a massive water bill and a stream of "high-strength" wastewater that's expensive to discharge into the municipal sewer.

Brother Isaäc looks at the schematic again. For Benedictine monks, work is prayer, and stewardship of the Earth—rentmeesterschap—is a sacred duty.18

"When can you start?"

The Terrestrial Adaptation

The "BioMakery" project integrated MELiSSA-derived advanced membranes (micro- and reverse osmosis) to treat the brewery's wastewater.

The Bottom Line (KPIs):

Before, their wastewater—a yeasty, sour-smelling brew of hops and sugars—was a costly problem. Now, the system polishes that water, making it clean enough for reuse in irrigation and bottle-washing.18 The pilot demonstrated 90% COD (Chemical Oxygen Demand) reduction and 95% conductivity reduction. Critically, even when the pre-treatment reactor underperformed, the MELiSSA membranes were robust enough to handle the worse-than-expected influent and still produce water that was "at or above expectations".12

Why This Is More Than a "Green" Project:

This pilot is more than a "green" project; it's a "bankable" solution. A sweeping 2025 revision to the EU's Urban Waste Water Treatment Directive (UWWTD) (Directive (EU) 2024/3019), adopted in late 2024, for the first time mandates micropollutant removal and "Extended Producer Responsibility" (EPR)—forcing polluters (like cosmetic and pharmaceutical companies) to help pay for the cleanup. The directive also mandates "energy neutrality" and "water reuse".

The La Trappe model is a perfect blueprint for how a utility can meet all these new, funded mandates at once. A city manager can now use the new EPR funds, combined with EIB green bonds, to finance a MELiSSA-style pilot, transforming a cost center (waste) into a compliant, circular-economy asset (reuse water and fertilizer).

From Waste to Gold: The URIDIS Revolution

It's not just wash water. A MELiSSA spin-off company called Hydrohm commercialized the URIDIS system to tackle urine.4 Born from the MELiSSA PhD (POMP) program, URIDIS is a 2020 spin-off from Ghent University. It uses an electrochemical reactor—no added chemicals—to turn urine into three separate value streams:

Recovered nutrients (like nitrogen and phosphorous) for fertilizer.
A disinfectant (hypochlorite) generated in-situ from the salts in the urine itself.
Clean, pathogen-free flush water, saving up to 60% of water consumption.

This isn't just theory; the innovative electrochemical cell at the heart of URIDIS is the subject of a specific MELiSSA-community patent (WO2021152090A), proving the direct, licensable path from lab to market.

The Standardization Framework

For a procurement manager at an airport (Hydrohm's target market)16, this tech is only viable if it's safe. That's where ISO 30500 comes in. This global standard, revised in 2025, is the "blueprint" for "Non-sewered sanitation systems" (NSSS). It provides the "General safety and performance requirements for design and testing". It makes the technology certifiable, insurable, and—most importantly—bankable by giving a procurement manager a global standard to trust.

Case Study 3: The Place to Pee—Confronting the Urine Revolution

July 6, 2021 – Blaarmeersen Park, Ghent, Belgium [Composite scene based on "The Place to Pee" opening day reports and visitor feedback]

The shipping container looks innocuous. White. Clean. A sign in Dutch and English: "THE PLACE TO PEE: Help Us Test the Future of Toilets." Inside: two urinals, three source-separating toilets (LAUFEN's "save!" model—the first mainstream urine-diverting toilet that doesn't require you to aim or think differently). Behind a glass partition, visible but contained: the URIDIS system. Tanks. Electrodes. Tubing. A small screen showing real-time nutrient recovery stats.

The first visitor, a middle-aged man in cycling gear, hesitates at the threshold. He reads the educational poster: "Your urine will be turned into fertilizer and disinfectant. The treated water will flush this toilet." He looks at the toilet. Back at the poster. At the toilet again. He uses it.

Afterward, he washes his hands and peers through the glass at the URIDIS unit. A staff researcher—monitoring the pilot from a small desk—asks if he has questions.

"So... the water I just flushed with...?"

"Came from someone else's urine earlier today. Treated, disinfected, pathogen-free."

Long pause. "Huh."

"How do you feel about that?"

Another pause. "Honestly? Fine, I guess. It's just... weird that I don't feel weirder about it."

By the end of summer 2021, over 3,500 visitors would use this facility. 14 Most had the same reaction: initial squeamishness, followed by... acceptance. Curiosity. Even pride.

The "Ick" Factor: Overcoming the Psychology of Recycled Water

But let's be honest. The technology is the easy part. The hard part is the human part. How do you convince someone to drink recycled urine?

On the International Space Station, they joke that their "Water Processor" turns "yesterday's coffee into tomorrow's coffee." But getting there is a mental game. You have to consciously override a primal, deep-seated disgust.30 This is the "ick factor," and arguments about "chemical purity" do not work.32

The good news? This is a solved problem. Pioneers in potable reuse, like Windhoek, Namibia (the original, since 1968) and Singapore's NEWater program, have created a 4-step playbook for overcoming the 'ick factor'.

Purity Framing: Never call it "toilet-to-tap". Singapore's "NEWater" is brilliant branding, framed positively around high-tech and national "self-sufficiency".
Radical Transparency: Build trust with independent audits. NEWater is subject to "rigorous audit processes annually" by "local and international... experts" and benchmarked against WHO and U.S. EPA standards.
Public Engagement: Make it a "science museum." The NEWater visitor center has hosted nearly a million visitors, treating public engagement as a "core operational function".
Benefit-Led Comms: Highlight the gains (water security, economic prosperity), which psychologically makes the perceived risk feel smaller.

Case Study 2: Better Cava, Thanks to a Space Sensor

Controlling a large-scale, living biological process—like fermenting wine or cheese—is an art. A tiny shift in temperature or yeast activity can change the taste, or even ruin an entire batch.

The Space Insight: The MELiSSA loop is a giant, living biological process. It cannot be "art." It must be a science. To keep it stable, ESA developed hyper-reliable sensors to monitor the bacteria and algae in real-time.

The Terrestrial Adaptation: The team at Freixenet, the famous Spanish Cava producer, had this exact problem. They adapted a MELiSSA-origin sensor—the "Biomass Scan System (NTE probe)"—and installed it directly into their massive fermentation vats.3

The Bottom Line (KPIs): This new sensor doesn't use light (optics), which is "inaccurate at high concentrations and when air bubbles" are present. Instead, it uses "electrical capacitance" to measure the yeast concentration. For the first time, their engineers had a real-time, non-invasive window into the fermentation process. The result? Tighter quality control, better consistency, and less product waste. This technology was validated in MELiSSA Technical Note 83.4.

Mid-Page Call to Action

Want to build your own loop? You don't need a rocket, but you can start with a soda bottle. For teachers and parents, check out ESA's guide to building a simple "bioreactor" in your classroom. This is that magic moment a 10-year-old sees with their own eyes how "waste" (their own breath) can become a resource (food for algae) and produce oxygen. It's the MELiSSA principle in a bottle.

Voices from Granada 2025: The AI Debate

October 7-9, 2025 – Parque de las Ciencias, Granada, Spain [Composite based on 2025 MELiSSA Conference program and documented AI control research]

The conference hall is packed. On stage, three researchers are mid-debate about the future of life support: Dr. Marco Gatti from EnginSoft, a systems engineer who's built the first complete dynamical model of the MELiSSA loop; Dr. Sandra Ortega Ugalde from ESA's MELiSSA team; and a skeptical voice from the back—a veteran microbiologist who's been with the project since the 1990s.

The question on the table: Should we trust AI to control life-or-death systems in space?

Marco: "For the first time, we have a complete dynamical model that can simulate what-if scenarios, including system failure, for potential space missions. The AI doesn't just react—it predicts. It sees a bacterial crash coming three hours before any human would notice."

The Microbiologist: "And when it's wrong? When the model doesn't account for a mutation, a contamination, something we didn't program? You're telling me we hand over life support to an algorithm?"

Sandra: "We're not replacing humans. We're augmenting them. For 30 years, this project was fragile because it required constant human vigilance. Researchers burning out at 2 AM trying to save a crashing compartment. AI gives us resilience. It watches when we sleep."

The Microbiologist: "It also makes us complacent."

This is the tension at the heart of MELiSSA in 2025. The 2025 Conference themes include 'Advanced LSS modelling, simulation and control' and the 'Use of artificial intelligence', showing the project is now focused on the AI-driven autonomy that makes the loop viable. The technology works. The spin-offs are proven. But the human factor—trust, oversight, the willingness to depend on something you can't fully understand—remains the final frontier.

By the end of the session, there's no resolution. Just recognition: The loop we're building is as much psychological as biological. We're learning to let go.

Myth vs. Truth: The MELiSSA Project

MYTH: This is all just theoretical, "lab vibes" sci-fi.
TRUTH: This is deployable tech. The La Trappe brewery, Freixenet, and Hydrohm pilots are real-world case studies with public data. The global space economy hit $613 billion in 2024 and is projected to top $1 trillion by 2032, according to the Space Foundation's 2025 reports. That growth is fueled by terrestrial ROI, not just exploration.

MYTH: If this tech is 30 years old, it must be outdated.
TRUTH: It's 30 years of R&D, but it's finally ready for primetime because of AI-driven control systems. For decades, the loop was fragile. Now, AI and advanced modeling—a key topic at the 2025 MELiSSA Conference in Granada (Oct 7-9)1—can act as the "digital twin" brain, predicting a bacterial crash before it happens. Session themes like 'Advanced LSS modelling, simulation and control' and the 'Use of artificial intelligence' show the project is now focused on the AI-driven autonomy that makes the loop viable.

MYTH: This is just a niche ESA project.
TRUTH: It's a proven solution in a new space race. NASA's ECLSS on the ISS is a marvel, but it's a different (physico-chemical) approach. China's 3-part Tiangong space station is already using its own regenerative life support system that recycles urine. Commercial players know they can't get to Mars without cracking life support. MELiSSA is no longer just an experiment; it's a licensable, autonomous system ready for that trillion-dollar market.

How to Engage the Pipeline: A 2-Step Playbook for Builders

So, you're an investor, a municipal water manager, or an ops lead at a food & bev plant. You're convinced. "How do I license this?" It's not a secret. ESA has a dedicated commercial pipeline.

Step 1: The Front Door (ESA TTPO)

Your first call is the ESA Technology Transfer Programme Office (TTPO). This is their top-level office, and their entire job is to find commercial partners to spin-out space tech.

Step 2: The Specialist (SEMiLLA IPStar)

TTPO will almost certainly connect you with SEMiLLA IPStar. Think of them as the official "technology transfer partner of the MELiSSA consortium". They are the specialists who bridge the gap from the lab to your factory floor.45 They manage the IP portfolio and will work with your team to:

Identify the exact MELiSSA patent for your problem.
Help you license the technology.
Co-design a pilot project and define the KPIs for your business case.

MELiSSA Spin-Off Technology Snapshot

Technology / Spin-Off	MELiSSA Origin	Terrestrial TRL	Primary Terrestrial Market
URIDIS (Hydrohm)	MELiSSA POMP (PhD)4	TRL 7-8 (System prototype / Pre-commercial)16, 47	Non-sewered sanitation (airports, venues)
Biomass Scan System	MELiSSA Side Project (NTE)3	TRL 9 (In-use, full production)3	Industrial process control (fermentation)
BioMakery Membranes	MELiSSA R&D[17]	TRL 6-7 (System prototype demonstration)[13]	Industrial wastewater polishing (circular reuse)

Reflection Point: The Cost of Building a Loop

Barcelona, 2025 – MELiSSA Pilot Plant [Based on documented MELiSSA leadership statements]

Christophe Lasseur stands in the observation room, watching the photobioreactor hum. Green algae spiraling in the light. Rats breathing in their airtight habitat. Thirty years.

"People ask me why I stayed," he says to no one in particular. "Why not take a safer project? Why spend a career on something that failed more than it succeeded?"

He watches the oxygen levels on the screen. Steady. The loop is holding.

"Because waste is a failure of imagination. Every time we turned a crash into a design improvement, every time a spin-off partner made this work on Earth, we proved that closed loops aren't just possible—they're inevitable. We just had to be stubborn enough to outlast the failures."

MELiSSA is regarded by members as a 50-year effort, resulting so far in hundreds of academic papers, patents and terrestrial spin-offs in areas ranging from food preparation to water purification and microbial safety. ESA

Thirty years down. Twenty to go.

Giving You Those Eyes Back

When you're overwhelmed by the world's problems—water scarcity, waste, pollution—it's easy to feel hopeless. But the MELiSSA project offers a different perspective. It reframes our biggest problems as engineering challenges. It proves that waste is a failure of imagination.

What MELiSSA teaches us, through 30 years of failure and persistence, is that everything is a resource. Urine isn't waste; it's water, fertilizer, and disinfectant. CO2CO_2 CO2 isn't just a pollutant; it's food for algae that produces oxygen. It teaches us to stop thinking in lines (take-make-waste) and start thinking in loops.

Space doesn't just give us perspective by showing us a picture of our planet. It forces us to invent the tools to save it.

The Future Is a Closed Loop

What starts as a survival tool for three astronauts on Mars becomes a sustainability tool for eight billion people on Earth.

The lesson from MELiSSA is simple. We have to stop wasting. Earth is finally listening. The technology to build a circular, sustainable economy isn't 30 years away. It's here right now, waiting for a business case.

Here's how you can join the loop:

Good (The Explorer): Share this article with a friend, a colleague, or your local city councilor. Start the conversation.
Better (The Guide): Are you a teacher or parent? Try the ESA classroom project and show a kid what a circular economy looks like.
Best (The Builder): Are you an investor, ops lead, or engineer? Explore the SEMiLLA IPStar technology portfolio. The next great circular economy company could be built on a patent that was designed for the Moon.

MELiSSA isn't a promise. It's a purchase order.

Frequently Asked Questions (FAQs)

1. What does MELiSSA stand for?

MELiSSA stands for Micro-Ecological Life Support System Alternative. It's the European Space Agency's (ESA) long-term project to create a self-sustaining, closed-loop life support system for long-duration space missions.

2. Is the Spirulina (algae) from MELiSSA safe to eat?

Yes. Arthrospira, or Spirulina, is a well-known "superfood" already on the market. The ArtemISS experiment on the ISS confirmed that the algae grown in the MELiSSA photobioreactor is a safe, effective, and protein-rich food source and oxygen producer. Astronauts who have tested it in bars report it's "earthy" or "nutty" but mostly takes on the flavor of what it's mixed with.8

3. What's the main difference between MELiSSA and the life support on the ISS?

The current ISS system (NASA's ECLSS) is primarily a "physico-chemical" one. It uses machines, catalysts, and chemical reactions to recycle water and scrub CO2CO_2 CO2. It's fantastic, but it's not fully "closed" and doesn't produce food. MELiSSA is a "bioregenerative" system that uses living organisms (bacteria, algae, plants) to do the same job, plus grow food.5

4. How can my company get involved with MELiSSA technology?

The best way is to contact the ESA Technology Transfer Programme Office (TTPO) or their official MELiSSA consortium partner, SEMiLLA IPStar.44 They are set up to help terrestrial companies license ESA patents and develop pilot projects.46

5. Is this technology just for big corporations?

No. Many of the spin-offs, like Hydrohm (sanitation)4, started as small, focused startups from university research or within the ESA Business Incubation Centre (BIC) network. The tech transfer program is designed to support entrepreneurs and startups.

6. What about the rats? Are they harmed?

The rats used in MELiSSA Pilot Plant experiments "do no work at all—they simply breathe" in carefully controlled comfort before being returned to university veterinary services. ESA They are under close veterinary supervision throughout. The ethical complexity is real, but the alternative—testing unproven life support systems on humans or delaying development by decades—poses greater risks.

Information last checked October 2025. This article is for general information purposes only and is not intended as investment, financial, or engineering advice. Always conduct your own due diligence. (MELiSSA Foundation, ESA, Space Foundation)

Floating Humans: Life Beyond Earth

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The 400-Kilometer Commute: Life Inside the International Space Station