Emerging Energy Sources: Airborne Wind, Algae Fuel and Waste-to-Energy

In 1954, Lewis Strauss, chairman of the US Atomic Energy Commission, predicted that electricity would one day be “too cheap to meter.” Although that has not been achieved, there have been important advances in electricity production over the years.

Many of these options depend on renewable natural resources, such as the sun, wind and water.

In the future, civilizations will be forced, even more than they are now, to look for new energy sources to meet their growing demand for resources. At the current rate of fossil fuel consumption, we are decades away from running out of them and triggering a global energy crisis unless an effective substitute is found to meet consumers’ needs. According to BP, proven reserves in 2020 were equivalent to just over 50 years of production for oil, about 49 years for natural gas and 139 years for coal.

When we talk about new energies, we do not mean new sources of energy but new methods and technologies that let us make better use of existing energy sources.

Although the pace at which new technologies are developed may seem slow, public awareness and pressure on governments are growing rapidly, and this is driving wider adoption of cleaner technologies.

Airborne wind farms

The concept studied at NASA in 2010 involved flying kites that act as turbines, moving at high altitude and sending the energy they generated down to the ground through nanotubes.

The kites could be funnel-shaped airships with a turbine at the back, a balloon with spinning blades, a parachute, a kite and so on. At the time, all of these were ideas being considered by the nascent renewable energy industry.

This concept does not require large amounts of land, is not labor-intensive and does not pollute. The generators could stay aloft for a year and then be brought down for inspection or in the event of a storm. Since then, the sector has had setbacks: in 2020, Alphabet shut down Makani, its airborne wind turbine company.

Algae for biofuel production

Producing ethanol from corn or sugarcane is already a major global industry, but it has also meant that large tracts of land once used to grow food are now fields for producing fuel.

According to research at the University of Arkansas reported in 2011, common algae can be turned into fuel. They can be grown in trench-like troughs about two feet (60 cm) wide and harvested every 5 to 8 days.

To produce the fuel, the algae are scraped off and dried, and then the carbohydrates are extracted and converted into sugars. Next, through fermentation, the sugars are converted into butyric, lactic and acetic acid, and a second fermentation turns the butyric acid into butanol, a fuel.

According to that report, this new process is less expensive and more efficient, and it also helps reduce water pollution, because the algae absorb excess nitrogen and phosphorus from the water.

Generating energy from waste

Pellets

Massive population growth, together with modern consumption habits, has resulted in the generation of enormous amounts of waste. Treating it has always been a problem, but new technological solutions with the potential to turn waste into energy are emerging. Some of them are:

Thermochemical conversion:

Burning the waste creates heat that is used to heat water and produce steam, which steam turbines then convert into energy. This includes the combustion, pyrolysis and gasification of waste.

Biochemical conversion:

Anaerobic digestion, the breakdown of biodegradable material by microorganisms in the absence of oxygen, produces biogas that can be used to generate electricity or heat.

Physicochemical conversion:

This process turns the combustible fraction of waste into high-energy fuel pellets that can then be used to generate steam or heat. They are similar to pieces of coal but are cleaner and free of noncombustible materials.

Power plants in the sky

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In 2013, an English company (New Wave Energy UK) planned to build the first high-altitude power plant using networks of drones (unmanned aerial systems). These would collect energy from multiple sources and then transmit it wirelessly to receiving stations on the ground. The drones would harvest both solar and wind energy while flying at low speed following the sun, and they would operate at high altitudes, where winds are more stable and the chances of weather events and interference with aircraft are minimal. The company was dissolved in 2016.

Global investment in energy transition technologies reached a record $2.3 trillion in 2025 (BloombergNEF).

Last updated: September 26, 2026