Generating Electricity From the Cold Night Sky

A device that generates electricity from temperature differences, drawing heat from below and radiating it into the night sky (source)

by Thomas Neuburger

Large streams from little fountains flow,
Mighty oaks from little acorns grow.
— Folk proverb

In the race against time to mitigate the coming climate tsunami, people of this century often turn to the hope that the "miracle of science" will save us. Usually this takes the form of some flavor of geoengineering — seeding the sky with debris (technically, aerosols) in an attempt to emulate the global dimming caused by volcanic eruptions, such as Mount Pinatubo in 1991 — or that ultimate unicorn, artificial "carbon capture and storage" (CCS) techniques, which don't exist at any scale worth mentioning.

After all, this generation has seen greater advances in science than any generation ever born. Science has put a man on the moon, exploded the atom, put 75" television screens as thin as your hand in every American home that wants one, connected virtually all of the country to a small set of (billionaire-controlled) minds in the guise of "entertainment" and to each other in the guise of inescapable mobile device–based "social media."

If science could do all that, why couldn't it save us from something as simple as global warming. How hard could it be to re-cool the earth?

Sadly, this isn't going to happen. The earth will be recooled only in the way it always is — through natural processes.

What may happen, though, is a vast reduction in carbon-based energy usage via discoveries like the one below, through ways to generate power from renewable sources unimagined even yesterday. (To quit carbon, though, our billionaires would have to be made to want to, but that's a side note to this discussion.)

Heat From the Cold Night Sky

Consider this: A "solar" panel that draws heat from its lower side, moves that heat to its upper side and radiates it into the cool night sky, and from this simple transfer, generates electricity. That electricity powers the stations that warm your homes. Heat from the darkness of space.

From the study's Summary (emphasis mine):

A large fraction of the world’s population still lacks access to electricity, particularly at night when photovoltaic systems no longer operate. The ability to generate electricity at night could be a fundamentally enabling capability for a wide range of applications, including lighting and low-power sensors. Here, we demonstrate a low-cost strategy to harness the cold of space through radiative cooling to generate electricity with an off-the-shelf thermoelectric generator. Unlike traditional thermoelectric generators, our device couples the cold side of the thermoelectric module to a sky-facing surface that radiates heat to the cold of space and has its warm side heated by the surrounding air, enabling electricity generation at night. We experimentally demonstrate 25 mW/m 2 of power generation and validate a model that accurately captures the device’s performance. Further, we show that the device can directly power a light emitting diode, thereby generating light from the darkness of space itself.

As this write-up at OilPrice.com notes, the process works, but is still in the beginning stages with respect to scale. "The technology is still under development, and the researchers have already planned improvements including enhanced insulation around the top plate that could potentially raise the device’s energy production to 0.5 watts per square meter or more, but the potential outcomes are boundless. If this technology could eventually be refined to produce anywhere close to as much energy as a standard solar panel, it would completely transform the renewable energy sector, making it a far greater contender to take the place of fossil fuels."

It may take a while (though one hopes not), but this is well beyond the concept state. It's entirely new, yet entirely realistic. The whole of the airline industry, the vast and ho-hum world of global travel, started with a powered glidere flight at Kitty Hawk of just 120 feet.

From little acorns...