This is a picture of a storm as it is building up over an uncultivated  agricultural field and some wind turbines in the horizon. It was shot at a location in the eastern part of the Netherlands.

1150911472

This is a picture of a storm as it is building up over an uncultivated agricultural field and some wind turbines in the horizon. It was shot at a location in the eastern part of the Netherlands.

Photo by: George Pachantouris

George Pachantouris

Raindrop Electricity: Generating 'Blue Energy' from Rainfall

By: Robin Fearon

Water-power has been used for thousands of years as a renewable energy source, so what are we doing today to make rain water work for us?

August 31, 2020

The ancient Greeks and Romans used water wheels to mill grain and refine wool in clothmaking. In the twentieth century, the same principles led to huge hydroelectric generation projects, but scientists have discovered a more efficient method of rainwater energy harvesting that could be scaled up.

Water Power

Photo taken in Aberystwyth, United Kingdom

1170860550

Photo taken in Aberystwyth, United Kingdom

Photo by: Jake Gardener / EyeEm

Jake Gardener / EyeEm

Raindrop electricity generation has previously been employed as a form of microgeneration to power houses and small water purification systems – by capturing and funnelling rainwater to drive small turbines. Another method used piezoelectric materials that generate electricity based on energy released when raindrops hit a surface.

But the method discovered by researchers at universities in China, Hong Kong, and the US, uses a triboelectric (static electricity) nanogenerator to generate and store electricity in materials. “Our research shows that a drop of 100 microliters [one microliter = one millionth of a liter] of water released from a height of 15 cm can generate a voltage of over 140V. And the power generated can light up to 100 small LED light bulbs,” said Professor Wang Zhong Lin of City University, Hong Kong.

Traditional hydropower generation technologies are not capable of generating proportionally anywhere near the same power for their size and only work efficiently with huge volumes of water. Materials used in this new droplet-based electricity generator combine a polytetrafluoroethylene film with an indium tin oxide electrode and aluminium electrode. When raindrops hit the device, they bridge the components to create a closed-loop electrical system.

Kinetic energy from falling raindrops is effectively turned into electrical energy. Surface charge accumulates on the device as the drops hit and is then discharged as spreading water connects the two electrodes. Power density and energy conversion efficiency achieved by this system is thousands of times greater than similar devices.

Power Limitations

Newly constructed tidal power generating turbine mounted on a test platform.

822150032

Newly constructed tidal power generating turbine mounted on a test platform.

Photo by: shaunl

shaunl

Newly constructed tidal power generating turbine mounted on a test platform.

Limitations in current technology mean that the low-frequency kinetic energy in rainfall, waves, and ocean tides are not being harvested efficiently. Tidal power and wave generation are potentially the most abundant renewable energy source available to humans given that the Earth's surface is about 70 per cent water.

American households are among the most energy-hungry on the planet, consuming on average around 11,000 kilowatt-hours (kWh) of energy each year. Electric water heaters alone use between 380-500 kWh per month. So developing generation from natural tidal movement would appear to be one of the best ways to meet demand and reduce greenhouse gas emissions.

While there are fairly few large tidal power projects worldwide, research continues and wave generation using piezoelectric and triboelectric materials could revolutionize so-called 'blue-energy' sources. Professor Wang points out that his droplet generator is effective in fresh and salt water so could be used virtually anywhere.

Next Up

These Scientists Created Robots Covered in Living Skin

Japanese scientists created a self-healing skin for robots. This breakthrough study brings Westworld-like robots one step closer to reality.Is a dystopian future closer than we think?

Robots Imitate Life to Create Better Versions of Themselves

Robots have always imitated life. Social androids powered by artificial intelligence have now reached a level where they may be ready to work in shops, airports, and care homes. But an entirely new class of robots is being developed that can grow, evolve, and even reproduce.

How 3D Print Building is Changing the Future

Building with 3D printing technology is sparking widespread interest in the construction industry. Besides reducing waste and our impact on the environment, it can speed up construction from weeks, or months, to days. Projects that use simple raw materials like soil, straw, and even salt, can be built in a fraction of the time and cost of traditional construction.

Food Growers Use AI and Robotics to Tackle Pest Problem

Farmers around the world face serious challenges in growing food more effectively. Climate warming increases the risk of crop damage from insects, fungi, and bacteria. So to manage the threat farms are turning to artificial intelligence (AI), robotics, and computer vision to target pests more effectively.

Plucking CO2 from the Air Could Decarbonize Food, Fuel, and Fashion

Products made from carbon dioxide (CO2) captured from the atmosphere are part of a fast-growing trend to decarbonize nearly everything we use. Food, drink, fuel, and plastics can all be made using CO2 from the air. And recycling carbon could create a circular economy that vastly reduces pollution and waste.

Scientists in China Discover Rare Moon Crystal that Could Power Earth

A rare lunar crystal found on the near side of the moon is giving scientists hope of providing limitless power for the world – forever.

Astronomers May Have Found a Rare “Free-Floating” Black Hole

How do you see a perfectly black object in the middle of a pitch-dark night? It sounds like the start of an annoying riddle, but it’s really the question faced by astronomers when they want to search for black holes.

Saving Baby Elephants from a Deadly Herpes Virus

One biotechnology company is accelerating efforts to eradicate a fatal disease affecting endangered elephants.

Saving Earth from Killer Asteroids

Only about 40% of an estimated 25,000 near-Earth asteroids with the potential to destroy the planet have been detected. Scientist Dr. Ed Lu, along with his nonprofit B612 are working to create a way to detect the other 60%.

113 Million-Year-Old Dinosaur Tracks Uncovered Due to Drought

Severe drought conditions dried up a river at Dinosaur Valley State Park in Texas leading to the pre-eminent discovery.