New Bandage Speeds Skin Healing By Using Electric Stimulation

It’s cool that the bandage worked well on rats (which are used in scientific experiments due to having some important similarities to humans) by using electric stimulation created by an electric field.

Skin has a remarkable ability to heal itself. But in some cases, wounds heal very slowly or not at all, putting a person at risk for chronic pain, infection and scarring. Now, researchers have developed a self-powered bandage that generates an electric field over an injury, dramatically reducing the healing time for skin wounds in rats. They report their results in ACS Nano.

Chronic skin wounds include diabetic foot ulcers, venous ulcers and non-healing surgical wounds. Doctors have tried various approaches to help chronic wounds heal, including bandaging, dressing, exposure to oxygen and growth-factor therapy, but they often show limited effectiveness. As early as the 1960s, researchers observed that electrical stimulation could help skin wounds heal. However, the equipment for generating the electric field is often large and may require patient hospitalization. Weibo Cai, Xudong Wang and colleagues wanted to develop a flexible, self-powered bandage that could convert skin movements into a therapeutic electric field.

To power their electric bandage, or e-bandage, the researchers made a wearable nanogenerator by overlapping sheets of polytetrafluoroethylene (PTFE), copper foil and polyethylene terephthalate (PET). The nanogenerator converted skin movements, which occur during normal activity or even breathing, into small electrical pulses. This current flowed to two working electrodes that were placed on either side of the skin wound to produce a weak electric field. The team tested the device by placing it over wounds on rats’ backs. Wounds covered by e-bandages closed within 3 days, compared with 12 days for a control bandage with no electric field. The researchers attribute the faster wound healing to enhanced fibroblast migration, proliferation and differentiation induced by the electric field.

Negative Energy Pricing Becoming More Common as Clean Energy Outdoes Fossil Fuels

Imagine living in a world where one of the most significant threats in the decades ahead is for the most part not being properly addressed, and is in many ways being exacerbated. The threat is climate change, and for one thing, it’s being exacerbated by having massive fossil fuel subsidies instead of massive clean energy subsidies. This is of course despite clean energy already regularly outcompeting fossil fuels.

Bright and breezy days are becoming a deeper nightmare for utilities struggling to earn a return on traditional power plants.

With wind and solar farms sprouting up in more areas — and their power getting priority to feed into the grid in many places — the amount of electricity being generated is outstripping demand during certain hours of the day.

The result: power prices are slipping to zero or even below more often in more jurisdictions.


Periods with negative prices occur when there is more supply than demand, typically during a mid-day sun burst or early morning wind gust when demand is already low. A negative price is essentially a market signal telling utilities to shut down certain power plants. It doesn’t result in anyone getting a refund on bills — or in electric meters running backward.

Instead, it often prompts owners of traditional coal and gas plants to shut down production for a period even though many of the facilities aren’t designed to switch on and off quickly. It’s left the utilities complaining that they can’t earn the returns they expected for their investment in generation capacity.

First Electrified Road for Charging Vehicles is Now Open in Sweden

An amazing innovation that should be deployed much more broadly to drastically reduce dependence on fossil fuels.

The world’s first electrified road that recharges the batteries of cars and trucks driving on it has been opened in Sweden.

About 2km (1.2 miles) of electric rail has been embedded in a public road near Stockholm, but the government’s roads agency has already drafted a national map for future expansion.

Sweden’s target of achieving independence from fossil fuel by 2030 requires a 70% reduction in the transport sector.

The technology behind the electrification of the road linking Stockholm Arlanda airport to a logistics site outside the capital city aims to solve the thorny problems of keeping electric vehicles charged, and the manufacture of their batteries affordable.

Energy is transferred from two tracks of rail in the road via a movable arm attached to the bottom of a vehicle. The design is not dissimilar to that of a Scalextric track, although should the vehicle overtake, the arm is automatically disconnected.

Hans Säll, chief executive of the eRoadArlanda consortium behind the project, said both current vehicles and roadways could be adapted to take advantage of the technology.

In Sweden there are roughly half a million kilometres of roadway, of which 20,000km are highways, Säll said.

“If we electrify 20,000km of highways that will definitely be be enough,” he added. “The distance between two highways is never more than 45km and electric cars can already travel that distance without needing to be recharged. Some believe it would be enough to electrify 5,000km.”

At a cost of €1m per kilometre, the cost of electrification is said to be 50 times lower than that required to construct an urban tram line.

Säll said: “There is no electricity on the surface. There are two tracks, just like an outlet in the wall. Five or six centimetres down is where the electricity is. But if you flood the road with salt water then we have found that the electricity level at the surface is just one volt. You could walk on it barefoot.”

National grids are increasingly moving away from coal and oil and battery storage is seen as crucial to a changing the source of the energy used in transportation.

Research: Wireless Energy Source that Generates Electricity from Simple Mechanical Motions Developed

This is cool research, but it’s difficult to determine how costly and efficient it would be at scale. Also, the W-TENG’s prototypical use of Teflon is definitely a concern, as Teflon’s C8 chemical is toxic to humans.

Researchers from Clemson’s Nanomaterials Institute (CNI) are one step closer to wirelessly powering the world using triboelectricity — a green energy source.

In March 2017, a group of physicists at CNI invented the ultra-simple triboelectric nanogenerator, or U-TENG — a small device made simply of plastic and tape that generates electricity from motion and vibrations. When the two materials are brought together — through clapping your hands or tapping your feet, for example — a voltage is generated that is detected by a wired, external circuit. Electrical energy, by way of the circuit, is then stored in a capacitor or a battery until it’s needed.

Nine months later, in a paper published in the journal Advanced Energy Materials, the researchers have uncovered a wireless version of TENG, called the W-TENG, which greatly expands the applications of the technology.

The W-TENG was engineered under the same premise as the U-TENG, using materials that are so opposite in affinity for electrons that they generate a voltage when brought in contact with each other.

In the W-TENG, plastic was swapped for a multipart fiber made of graphene — a single layer of graphite, or pencil lead — and a biodegradable polymer known as poly-lactic acid (PLA). PLA, on its own, is great for separating positive and negative charges, but not so great at conducting electricity — which is why the researchers paired it with graphene. Kapton tape, the electron-grabbing material of the U-TENG — was replaced with Teflon, a compound known for coating nonstick cooking pans.

“We use Teflon because it has a lot of fluorine groups that are highly electronegative, whereas the graphene-PLA is highly electropositive. That’s a good way to juxtapose and create high voltages,” said Ramakrishna Podila, corresponding author of the study and an assistant professor of physics at Clemson.

To obtain graphene, the researchers exposed its parent compound, graphite, to a high frequency sound wave. The sound wave then act as a sort of knife, slicing the “deck of cards” that is graphite into layer after layer of graphene. This process, called sonication, is how CNI is able to scale up production of graphene to meet the research and development demands of the W-TENG and other nanomaterial inventions in development.

After assembling the graphene-PLA fiber, the researchers exploited additive manufacturing — otherwise known as 3D printing — to pull the fiber into a 3D printer, and the W-TENG was born.

The end result is a device that generates a max voltage of 3000 volts — enough to power 25 standard electrical outlets, or on a grander scale, smart-tinted windows or a liquid crystal display (LCD) monitor. Because the voltage is so high, the W-TENG generates an electric field around itself that can be sensed wirelessly. Its electrical energy, too, can be stored wirelessly in capacitors and batteries.

“It cannot only give you energy, but you can use the electric field also as an actuated remote. For example, you can tap the W-TENG and use its electric field as a ‘button’ to open your garage door, or you could activate a security system — all without a battery, passively and wirelessly,” said Sai Sunil Mallineni, the first author of the study and a Ph.D. student in physics and astronomy.


As such, Podila says there is a definite philanthropic use for the team’s invention.

“Several developing countries require a lot of energy, though we may not have access to batteries or power outlets in such settings,” Podila said. “The W-TENG could be one of the cleaner ways of generating energy in these areas.”

The team of researchers, again led by Mallineni, is in the process of patenting the W-TENG through the Clemson University Research Foundation. Professor Apparao Rao, director of the Clemson Nanomaterials Institute, is also in talks with industrial partners to begin integrating the W-TENG into energy applications.

However, before industrial production, Podila says more research is being done to replace Teflon with a more environmentally friendly, electronegative material. A contender for the redesign is MXene, a two-dimensional inorganic compound that has the conductivity of a transition metal and the water-loving nature of alcohols like propanol. Yongchang Dong, another graduate student at CNI, led the work on demonstrating the MXene-TENG, which was published in a Nov. 2017 article in the journal Nano Energy. Herbert Behlow and Sriparna Bhattacharya from CNI also contributed to these studies.

Will the W-TENG make an impact in the realm of alternative, renewable energies? Rao says it will come down to economics.

“We can only take it so far as scientists; the economics need to work out in order for the W-TENG to be successful,” Rao said.

Germany Had Enough Energy to Essentially Pay People to Use It on Christmas

A clean energy surplus is a hopeful note for the future. Other countries besides should also make these big investments in renewable energy.

People in Germany essentially got paid to use electricity on Christmas.

Electricity prices in the country went negative for many customers – as in, below zero – on Sunday and Monday, because the country’s supply of clean, renewable power actually outstripped demand, according to The New York Times.

The phenomenon is less rare than you may think.

Germany has invested over US$200 billion in renewable power over the last few decades, primarily wind and solar.

During times when electricity demand is low – such as weekends when major factories are closed, or when the weather is unseasonably sunny – the country’s power plants pump more electricity into the grid than consumers actually need.

The disparity arises because wind and solar power are generally inconsistent. When the weather is windy or sunny, the plants generate a lot of electricity, but all that excess power is difficult to store. Battery technology is not quite advanced enough to fully moderate the supply to the grid.

So when the weather is hot, like it was in parts of Germany over the weekend, and most businesses are closed, plants generate an excess supply of power despite unusually low demand. Then it’s a matter of simple economics – prices, in effect, dip below zero.

It’s important to note that Germany’s utilities companies aren’t depositing money directly into consumer’s accounts when this happens. Rather, the periods of negative-pricing lead to lower electricity bills over the course of a year.


Traditional power grids – which mostly rely on fossil fuels to generate electricity – are designed so that output matches demand. But renewable energy technology hasn’t yet been developed to produce according to demand, since generation is a function of weather.

That’s “one of the key challenges in the whole transition of the energy market to renewable power,” Tobias Kurth, the managing director of Energy Brainpool, told the Times.

As storage technology lags behind the efficiency of renewable power sources, it’s likely that this negative-pricing situation will occur again. In that case, governments might need to provide incentives for people to increase their power usage when prices go negative.

These irregularities need to get figured out sooner rather than later, since renewable energy is growing rapidly, driven by the declining cost of technology and government subsidies. The International Energy Agency predicts that renewable energy will comprise 40 percent of global power generation by 2040.

In the next five years, the share of electricity generated by renewables worldwide is set to grow faster than any other source.

In Britain, renewable energy sources generated over triple the electricity as coal did in 2017, according to The Guardian. In June, during a particularly windy night, power prices actually went negative in Britain for a few hours as well – and it’s likely to happen again.