Harvesting power from the wind and the sun is nothing new. We've seen flying wind turbines and solar power plants that aim to provide clean renewable energy. UK-based New Wave Energy has a bolder idea in the works. The company plans to build the first high altitude aerial power plant, using networks of unmanned drones that can harvest energy from multiple sources and transmit it wirelessly to receiving stations on the ground.

The patent-pending technology aims to have drone networks hover in the sky harvesting both solar and wind power, while moving about at low speeds to keep track of the sun. The drones will operate at high altitudes where the winds are more stable and there's minimal chance of weather patterns or aircraft interfering with them.

"At 50,000 ft (15,000 m) there is very little air traffic and biodiversity, unless you go over the Himalayas," company director Michael Burdett tells Gizmag. "Implementing a system in these conditions will not obstruct any existing systems."

Each 20 x 20 m (65 x 65 ft) drone will have four rotors, multiple wind turbines and a flat base for generating solar power. It'll be able to power itself with the harvested energy and generate an additional 50 kW that can be transmitted wirelessly to the ground. Rectenna arrays installed inland or on offshore installations would receive the electromagnetic waves and convert them into usable power.

Burdett estimates that an aerial power plant containing thousands of drones could produce around 400 MW of power, enough to power over 205,000 homes annually. Designed to be easy to update, the drone networks can be outfitted with more efficient generators as they become available. A drone power plant capable of delivering so much power, the company says, would be pretty large, around twice the size of an offshore wind farm such as the Robin Rigg farm in the Solway Firth, Scotland.

Though it sounds quite ambitious, there have been a number of advances in drone design and technology that help give an aerial power plant some weight. Solara's UAV can stay airborne for up to 5 years and Quadrotor's UAVs are able to charge devices wirelessly. Getting a power-producing drone network airborne also offers other benefits, such as being able to link small aerial power plants to each other wirelessly to deliver large amounts of energy reliably.

The company states that it will be able to handle energy output within a drone network as efficiently as managing data in an information network. An aerial power plant also makes it easier to provide power to remote locations with long range transmissions, or help out immediately in the event of an emergency or a natural disaster.

"The time for a response in times of natural disaster depends on the drone's current location and flight speed once the final form is specified," Burdett says. "Using smaller drones of 50 to 100 kW will reduce implementation times. It would be feasible to produce a system to operate at lower altitudes if required, one which could be transported with other equipment for relief efforts and implemented instantly."

Aside of the obvious advantage of requiring little or no land space, the drone networks would be invisible to the naked eye making it realistic for them to be installed anywhere. The company aims to make use of the unpopulated airspace over the Atlantic, Indian or Pacific Ocean first. Burdett states that New Wave Energy will be able to deliver energy around the clock to many different parts of the world using solar, wind, thermoelectrics, infrared and visible spectrum rectennas.

It took around two years for New Wave Energy UK to develop the technology. The company plans to start a Kickstarter campaign to raise around £300,000 (US$500,000) and expects to have a working prototype within 6 months of receiving funding.

Source: New Wave Energy UK