A new portable energy source could power electronic devices using running water.

Estream is a new portable hydropower device that could convert running water into electricity that could be used to power smartphones and other USB devices.

Developed by South Korean startup Enomad (Energy Nomad), Estream is about the size of a water bottle and weighs at least 2 lbs. The portable generator features turbine blades, which are folded for easy storage and transport. Once dipped into running water, the turbine rotates and generates electricity, which will be stored in Estream's built-in 6,400mAh lithium-ion battery that takes about 4.5 hours to charge, Digital Trends reports.

The device can be used to charge mobile gadgets through a standard USB port and could also double as a lantern, as it comes with LED lights with two lighting modes and strobe settings for signaling and SOS.

"[Our] goal is not only to make the most powerful portable green energy available to backpackers and hikers; it is also to take clean, affordable electricity to parts of the world that have never experienced it before," the company, which is now based in Los Angeles, said in its Kickstarter campaign page.

While users could not charge their gadgets while the Estream is generating power like they do with solar chargers, the device could be left in a stream overnight to charge fully, without the need for sunlight. In absence of a water stream, users can also attach the device to the end of a kayak to generate electricity from the movement.

The developers conducted a field test of the device in Provo river near Salt Lake City to determine how well it could fare in extreme weather conditions. They found that Estream could still generate energy from water stream even in the cold weather.

"Recommended temperature range for Estream is from 23 degrees Fahrenheit to 104 degrees Fahrenheit but our engineers are trying to improve battery life and conditions for wide range of outdoor activities," Hyerin Park, founder and CEO of Enomad, said in a statement.

According to Park, Estream is designed to work in freshwater, but the developers are now working on upgrades to make the device compatible with ocean water.

The company has launched a Kickstarter campaign and has already raised 163 percent. Estream will retail at $250 when the device starts shipping in January 2017.