Five inventions that could help tackle global water scarcity

Water scarcity is becoming one of the defining constraints of this decade. Only about 2.5% of the planet’s water is freshwater, and as populations grow and climate extremes intensify, saving water — and using it more efficiently — becomes a practical necessity, not just an environmental ideal.

Over the past year, researchers and startups have been rolling out solutions that target the biggest “everyday” sources of water waste: showers, laundry, leaking fixtures, and off-grid water supply. Here are five of the most interesting ideas.

1) A laundry device that washes clothes using reused shower water

A typical washing machine uses roughly 50–80 litres of water per cycle — in a world where more than 2 billion people live in countries with inadequate water supply.

A UK company, Lylo Products, proposed a practical workaround: a device that washes clothes using recycled shower water.

The idea is simple. Water is collected in a removable reservoir placed on the shower floor, shaped like a bath mat. While you shower, the reservoir fills. The device then filters the collected water and uses it for washing.

According to the company, one benefit is behavioural: once people see greywater reuse working safely, it becomes easier to accept other forms of reuse. Lylo positioned students (especially those using campus laundries) as an early target group, because affordability and convenience matter most there.

Rather than rushing to mass production, the company said it planned pilot tests first — to validate usability and see how much water saving is realistic in everyday routines.

2) Solar-powered “eco distillation” from seawater

A UAE startup called Manhat developed a system that distils freshwater from the ocean using solar energy — without electricity or fossil fuels.

Its units are shaped like open-top pyramids with reservoirs that collect condensation from the inner walls. The technology essentially mimics a natural cycle: seawater evaporates, then condenses as freshwater — with sunlight providing the heat.

This kind of solution is most relevant for coastal and island regions, where freshwater access can be limited and climate impacts (including saltwater intrusion and sea-level rise) increase stress on supplies. Manhat said it has been experimenting with different formats to standardise the design for manufacturing and scale, with early deployment intended in places like Singapore.

3) A recirculating shower that reuses warm water instead of sending it down the drain

Long showers waste more than just water — they also waste the energy used to heat it.

A Danish company, Flow Loop, developed a recirculating shower system called Eco Loop. Unlike a conventional shower, it doesn’t continuously dump warm water into the sewer. Instead, the water circulates: it is collected, filtered, and sent back through the shower head repeatedly until the user finishes.

The system uses multiple treatment steps:

• a pre-filter and microfilter to remove large and small particles, 

• an ultrasonic cleaner to reduce limescale, 

• and a UV filter to inactivate bacteria and other microorganisms. 

Flow Loop claims the system can be added to an existing shower without major renovation, and installed in under half an hour. It also includes a pump that increases water pressure.

The price range cited is $4,000–6,000, with the company claiming fast payback through reduced water use (up to 85%) and lower energy use (up to 75%) compared with a standard shower.

4) A portable device that generates drinking water from air

Many people off-grid rely on portable electricity generators. An Israeli company, Watergen, applied a similar “self-sufficient” idea to water: a portable atmospheric water generator.

The device (Mobile Box) plugs into either 12V or 220V power — including a vehicle outlet. It draws in air with a fan, passes it through filters and a heat exchanger, condenses water from humidity, and then treats it (including UV) before storing it in a tank.

Watergen says the Mobile Box can produce about 20 litres per day, while a larger “On Board” version can produce up to 50 litres per day and be mounted on a vehicle roof.

The pitch is both practical and environmental: fewer plastic bottles and less dependence on transporting water — useful for travel, remote work, and emergency response.

5) Smart water meters and leak detectors that change behaviour (and catch silent waste)

A large part of water waste is invisible: slow leaks, inefficient routines, and the absence of real-time feedback.

A Danish company, Aguardio, developed sensors that track water use in the shower and show users how much water (and energy) they are consuming while they are still in the act — a behavioural nudge designed to shorten shower time. A second sensor attaches to a toilet outlet to detect leaky valves and alert users.

Data is sent to a cloud dashboard that shows water and energy use in real time. The company claims its own studies found shower water use dropped by around 30% after installation.

A similar approach comes from California-based Nudge Systems. Its Pleco “smart meter” attaches to a standard home water meter and provides real-time feedback on household water use — distinguishing patterns across showers, toilets, and washing machines, and identifying leaks.

These tools are especially relevant in buildings where water use is distributed across many users (hotels, apartment blocks, campuses) — and in parts of Europe where drought risk is increasing, making demand reduction a key part of resilience.