Creating Something From Nothing - Scientists Harness Darkness to Create Electricity

Scientists have found a way to power a light using the cold darkness of outer space, with a whole swathe of implications and usages for this technology. Using only $30 in equipment, they were able to generate enough electricity to power an LED light, thanks to a process called Radiative Coolling.

Solar panels are able to be fitted with batteries that can be charged for nighttime use, but they increase the cost of solar energy exponentially. So what is this process? And how can you get electricity from darkness?

01
Something from Nothing

via Scientists have found a way to use the cold of night to generate electricity | Digital Trends

This device, using the cold of space, uses a process called radiative sky cooling. Similar to the way solar panels work, but the change in night temperature is what causes the generation of energy,
But beyond just powering lights, this technology is hoped to allow power generation in some of the most remote locations, or anywhere where power is needed at night.
02
Magic Black Disk

via Scientists have found a way to use the cold of night to generate electricity | Digital Trends

Aaswath Raman, an associate professor at UCLA, along with two scientists from Stanford, Wei li and Shanuhui Fan, developed the device that uses a sky facing object, in this case the disk, passes its heat to the atmosphere in the form of thermal radiation. In the process, it loses some of its heat to space, and reaches a cooler temperature than the air surrounding it.
03
How Does it Work?

via Transformative? New Device Harvests Energy in Darkness | New York Times

Just like frost forms on grass during nights that are above freezing, the same process can be harnessed in order to generate electricity.
The uneven heat of the disc, with the top side cooler than the top, has that difference in that heat converted into electricity.
One of t he most amazing features of this device is that it can cool down. It doesn't require consistent heat generation in the process of or in order to generate power.
04
It Has Its Limits

via Transformative? New Device Harvests Energy in Darkness | New York Times

In 2014, scientists at Harvard calculated that a square meter of cold space can generate at most 4 watts of energy. By comparison, a photovoltaic panel, the most common form of solar panel, can generate around 200 watts per square meter in sunlight.
So the potential amount of energy that scientists can currently generate with darkness are exponentially smaller than what we get from solar energy. But that hasn't stopped scientists from exploring the capabilities of energy from darkness.
05
Glorified Tinfoil hat

via Generating light from darkness | CBC Radio

Using only $30 is pretty impressive considering the implications of the technology and demonstration they created. The device consisted of a Styrofoam-like box comparable to the size of the shoe box. It was covered in an aluminum like material, with a metal disk painted black in the middle, with an aluminum block on the inside of the box.
The key component though, was a thermometric generator attached to the disk? This is what allowed the scientists to harness the temperature change, and generate the electricity.