Scientists have found that floating solar panels could provide a huge amount of electricity if they were placed on lakes and other bodies of water around the world. Floating solar panels could also help save water and protect land.

Solar panels — also known as “photovoltaic” panels — are used to turn sunlight into electricity. Most solar panels are placed on land in large collections called solar farms. But recently people have begun to explore putting floating solar panels on water. Because these panels float, some people call them “floatovoltaies (浮动光伏)”.

The researchers behind the new study looked at 114,555 reservoirs (水库) worldwide. They used computer programs to figure out how much electricity could be produced yearly by covering 30% of these reservoirs with floating solar panels. The answer was surprisingly large — more than twice the amount of energy the United States generates in a year. And 10 times as much energy as all the solar power currently being generated in the world. The researchers described the results as “remarkable”.

The scientists found that floatovoltaies would be especially useful when reservoirs were near smaller cities (50,000 people or less). The researchers say there are about 6,256 cities around the world where floating solar panels could provide all the electricity the cities need.

Floatovoltaies can also help save water by limiting evaporation (蒸发) from reservoirs. The scientists say that solar panels covering just 30% of the reservoirs’ surfaces could save as much water as 300 million people would use in a year. There are several other reasons that make floatovoltaies a good idea. Photovoltaic panels work better when they’re not extremely hot. The water helps cool the panels so that they create more energy. Putting solar panels on water also means that there’s no need to clear land for a solar farm. That’s more and more important as countries work to fight climate change and protect natural spaces for wild animals.

A joint research team recently have developed a new electronic skin that is similar to human skin in strength, durability (耐用性) and sensitivity. The skin or e-skin may play an important role in next- generation personalized medicine, soft robotics and artificial intelligence.

“The ideal e-skin will mimic (模仿) the many natural functions of human skin, such as sensing temperature and touch, accurately and in real time,” says leading researcher Yichen Cai. However, making suitably flexible electronics that can perform such delicate tasks while also used repeatedly is challenging, and each material involved must be carefully engineered.

Most e-skins are made by putting an active sensor on the surface that attaches to human skin. However, the connection between them is often too weak, which reduces the durability and sensitivity of the material; otherwise, if it is too strong, it won’t be flexible enough, making it more likely to break the circuit.

“The landscape of skin electronics keeps shifting at a remarkable pace,” says Cai. “The discovery of 2D sensors has accelerated efforts to turn these quite thin but strong materials into functional, durable artificial skins.”

The new man-made skin built by the researchers could sense objects from 20 centimeters away. It could further make a quick response when touched in less than one tenth of a second. “It is a striking achievement for an e-skin to maintain toughness after repeated use,” said Yichen, “which mimics the softness and rapid recovery of human skin.”

This type of e-skin could monitor a range of biological information, such as changes in blood pressure, which can be detected from movements of arms and legs. This data can then be shared and stored on the cloud via Wi-Fi.

“One remaining problem to the widespread use of e-skins lies in mass production of high-resolution sensors,” adds group leader Vincent Tung, “However, the latest technology offers new promise.”

The beautiful island country of Madagascar has a serious school shortage. About a third of Malagasy children have no access to education because the schools are too far away or severely overcrowded. Thinking Hus, a non-profit dedicated to increasing global access to education, plans to tackle the issue with a series of 3D-printed schools, the first of which was completed in April 2022.

The 765-square-feet structure, named Bougainvillea, will house 30 students. The construction a began with the printer pouring a cement-like (水泥状) mixture in a pattern to create the walls. The entire process took just 18 hours! The roof, doors and windows were locally sourced, and the walls were made of a cement mixture that can resist big environmental pressures in the area. Bougainvillea was 3D printed by 14 Trees, a company with experience printing buildings throughout Kenya and Malawi.

Maggie Grouts, the 22-year-old founder of Thinking Huts, is a senior at the University of Colorado and was just 15 when she started Thinking Huts. Adopted from a rural village in China when she was 18 months old, Grout realized that not all kids were as fortunate as her and wanted to help. The idea for the 3D-printed schools came to her after brainstorming(集思广益) with her father on ways to use the technology for the greater good.

The 3D printing approach shrinks the construction turnaround time from months to days, as well as the cost. This allows more schools to be built in less time and reduces the building’s carbon footprints. And these savings in time, cost and materials meet a real need for education infrastructure (基础设施) to help bridge the global opportunity gap.

“Thinking Huts hopes to have a Thinking Hut in every community where children do not have a place for education and is fundraising to develop this goal. By using 3D printing, we are combining the potential of technology with architectural solutions that tackle real problems the world faces within education,” says Grouts.