A team of physicists and chemists at the University of Bristol have developed a new type of battery that could change the way we think of long-term energy storage and electricity generation. The researchers looked at the problem of nuclear waste and came up with a battery that uses a man-made diamond to turn that waste into nuclear energy without fear of contamination.

“There are no moving parts involved, no emissions generated and no maintenance required, just direct electricity generation,” said Professor of Materials Tom Scott. “By encapsulating radioactive material inside diamonds, we turn a long-term problem of nuclear waste into a nuclear-powered battery and a long-term supply of clean energy.”

The team has previously developed a working prototype using Nickel-63, but is now working on improving efficiency by using carbon-14, a radioactive version of carbon, that is found in the graphite blocks used to moderate nuclear reactions in nuclear power plants. In the UK alone there are 95,000 tons of these graphite blocks containing high concentrations of carbon-14. The carbon-14 can be extracted from these blocks and then turned into a man-made diamond, safely storing the nuclear waste as well as creating a nuclear-powered battery.

“Carbon-14 was chosen as a source material because it emits a short-range radiation, which is quickly absorbed by any solid material,” said Dr. Neil Fox, professor in the School of Chemistry. “This would make it dangerous to ingest or touch with your naked skin, but safely held within diamond, no short-range radiation can escape. In fact, diamond is the hardest substance known to man, there is literally nothing we could use that could offer more protection.”

The diamond battery is low power compared to conventional batteries, but could do something that no battery before it has: last thousands of years. The scientists at University of Bristol say that with carbon-14 as the radiation source, it would take 5,730 years for it to reach 50 percent power.

That type of lifetime would make these batteries well-suited for applications where a constant power source is needed but it is difficult to replace or charge batteries once they’re installed — think environmental and structural sensors, pacemakers, satellites, spacecraft and much more. The scientists say the list of potential uses is so vast, they’re taking suggestions from the public.

(Source: treehugger.com; November 28, 2016; http://tinyurl.com/j938vkd)

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One of the worst sources of pollution in New England will be home to clean, renewable energy.

The Mount Tom Power Station in Holyoke, Massachusetts—known as one of the worst polluters in New England—is on its way to a renewable rebirth.

The plant’s owners broke ground on a 5.76-megawatt solar farm in October on the site of the defunct coal-burning power station.

Activists had called for the closure of the plant for years, worried about the health effects burning coal was having on surrounding communities.

“This victory came after more than five decades spent inhaling soot and struggling to breathe and more than five years of organizing to retire and repurpose Mount Tom coal plant,” Claire Miller, lead community organizer for the Toxics Action Center, said in a statement.

More than 17,000 solar panels will be installed on the site, providing power to more than 1,000 homes.

The coal plant, which borders the Connecticut River, has been associated with the region’s perennially poor air quality since opening in 1960. Its owner, Paris-based Engie, decommissioned the plant in 2014 and plans to demolish it next year.

Engie, a $75 billion global energy company, said it shuttered the power plant because of competition from cheaper natural gas rather than as a result of pressure from environmentalists. Still, the company saw an opportunity to repurpose the site as a solar farm.

“For Engie, this project brings the concept of ‘Reduce, Recycle, Reuse’ to life,” Engie North America President Frank Demaille said in a statement. “It’s a unique opportunity to transform this property from a coal plant to a solar farm to serve the local community.”

The owners signed a 20-year agreement to sell the solar-generated electricity to Holyoke Gas & Electric. When the project comes online, the local utility—which provides power to 18,000 homes—will obtain more than 75 percent of its energy from renewable sources.

Now, environmental organizers are hoping Mount Tom will be a model for other communities.

“One of the advantages of a coal-fired power plant site is that it is already connected to the energy grid, so looking into whether a coal site can be used for renewable energy is something I hope every community looks to first,” said Miller.

Images: YouTube

For instance, the coal-fired Brayton power plant in Somerset, Massachusetts, is set to be shuttered next June. Houston-based Dynegy said it is weighing options for the site, including a proposal to convert the plant to a $1.3 billion, 400-megawatt natural gas power plant.

But environmental groups drafted a report outlining how the 234-acre waterfront site could host a 9-megawatt solar farm, a food waste digester, a large-scale battery storage facility, and a port to service offshore wind farms.

“This option would represent a ‘Clean Energy Hub’ scenario in which clean, renewable energy sources are brought together to provide reliable electricity, promote innovative new technologies, and reclaim the waterfront area from polluting large-scale industrial use,” the report stated.

(Source: takepart.com; November 6, 2016; http://tinyurl.com/o4uqgvo)

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A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers (ACS Photonics, “Perovskite Nanocrystals as a Color Converter for Visible Light Communication”).

While Wi-Fi and Bluetooth are now well established technologies, there are several advantages gained by shortening the wavelength of the electromagnetic waves used for transmitting information.

So-called visible-light communication (VLC) makes use of parts of the electromagnetic spectrum that are unregulated and is potentially more energy-efficient. VCL also offers a way to combine information transmission with illumination and display technologies–for example, using ceiling lights to provide internet connections to laptops.

Many such VLC applications require light-emitting diodes (LEDs) that produce white light. These are usually fabricated by combining a diode that emits blue light with phosphorous that turns some of this radiation into red and green light. However, this conversion process is not fast enough to match the speed at which the LED can be switched on and off.

“VLC using white light generated in this way is limited to about one hundred million bits per second,” said KAUST Professor of Electrical Engineering Boon Ooi.

Instead, Ooi, , Associate Professor Osman Bakr and their colleagues use a nanocrystal-based converter that enables much higher data rates.

The team created nanocrystals of cesium lead bromide that were roughly eight nanometers in size using a simple and cost-effective solution-based method that incorporated a conventional nitride phosphor. When illuminated by a blue laser light, the nanocrystals emitted green light while the nitride emitted red light. Together, these combined to create a warm white light.

The researchers characterized the optical properties of their material using a technique known as femtosecond transient spectroscopy. They were able to show that the optical processes in cesium lead bromide nanocrystals occur on a time-scale of roughly seven nanoseconds. This meant they could modulate the optical emission at a frequency of 491 Megahertz, 40 times faster than is possible using phosphorus, and transmit data at a rate of two billion bits per second.

“The rapid response is partly due to the size of the crystals,” said Bakr. “Spatial confinement makes it more likely that the electron will recombine with a hole and emit a photon.”

Importantly, the white light generated using their perovskite nanostructures was of a quality comparable to present LED technology.

“We believe that white light generated using semiconductor lasers will one day replace the LED white-light bulbs for energy-efficient lighting,” said Ooi.

(Source:  www.nanowerk.com; Aug 15, 2016; http://tinyurl.com/z2lv27q)

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