Tel Aviv, Israel (CNN) — An Israeli company says its air-to-water generator could benefit millions of people who don’t have access to clean drinking water.

Other companies already sell atmospheric water generators but Water-Gen says its device is more energy efficient.

It’s already been sold to militaries in several countries.

Water-Gen’s co-CEO Arye Kohavi says civilians in countries where drinking water is often not readily available can benefit from it.

Spring, a portable water purification system

The system produces 250-800 liters (65-210 gallons) of potable water a day depending on temperature and humidity conditions and Kohavi says it uses two cents’ worth of electricity to produce a liter of water.

Another product Water-Gen has developed is a portable water purification system. It’s a battery-operated water filtration unit called Spring. Spring is able to filter 180 liters (48 gallons) of water, and fits into a backpack — enabling water filtration on the go.

The World Health Organization estimates about 780-million people don’t have access to clean water.