Solar Power to Grow Sixfold as Sun Becoming Cheapest Resource

Photo: Simon Dawson/Bloomberg

By: Mahmoud Habboush  Claudia Carpenter

The amount of electricity generated using solar panels stands to expand as much as sixfold by 2030 as the cost of production falls below competing natural gas and coal-fired plants, according to the International Renewable Energy Agency.

Solar plants using photovoltaic technology could account for 8 percent to 13 percent of global electricity produced in 2030, compared with 1.2 percent at the end of last year, the Abu Dhabi-based industry group said in a report Wednesday. The average cost of electricity from a photovoltaic system is forecast to plunge as much as 59 percent by 2025, making solar the cheapest form of power generation “in an increasing number of cases,” it said.

Renewables are replacing nuclear energy and curbing electricity production from gas and coal in developed areas such as Europe and the U.S., according to Bloomberg New Energy Finance. California’s PG&E Corp. is proposing to close two nuclear reactors as wind and solar costs decline. Even as supply gluts depress coal and gas prices, solar and wind technologies will be the cheapest ways to produce electricity in most parts of the world in the 2030s, New Energy Finance said in a report this month.

“The renewable energy transition is well underway, with solar playing a key role,” Irena Director General Adnan Amin said in a statement. “Cost reductions, in combination with other enabling factors, can create a dramatic expansion of solar power globally.”

Solar Growth

Bloomberg New Energy Finance also forecasts growth in solar photovoltaics, reaching 15 percent of total electricity output by 2040, according to Jenny Chase, head of solar analysis in Zurich. “Irena’s assumptions are reasonable,” she said. “Solar just gets so cheap under any reasonable scenario.”

The “most attractive” markets for solar panels up to 2020 are Brazil, Chile, Israel, Jordan, Mexico, the Philippines, Russia, South Africa, Saudi Arabia, and Turkey, according to Irena. Global capacity could reach 1,760 to 2,500 gigawatts in 2030, compared with 227 gigawatts at the end of 2015, it said.

Smart grids, or power networks capable of handling and distributing electricity from different sources, and new types of storage technologies will encourage further use of solar power, Irena said.

As of 2015, the average cost of electricity from a utility-scale solar photovoltaic system was 13 cents per kilowatt hour. That’s more than coal and gas-fired plants that averaged 5 cents to 10 cents per kilowatt hour, according to Irena. The average cost of building a solar-powered electricity utility could fall to 79 cents per watt in 2025 from $1.80 per watt last year, it said. Coal-fired power generation costs are about $3 per watt while gas plants cost $1 to $1.30 per watt, according to Irena.

The record for the world’s cheapest solar tariff was set in Dubai last month in an auction. MEED reported that a consortium including Masdar Abu Dhabi Future Energy Co. and Saudi Arabia’s Abdul Latif Jameel bid 2.99 cents per kilowatt-hour, 15 percent cheaper than the previous record.


Ultra-thin Solar Cells Can Easily Bend Around a Pencil

Ultra-thin solar cells are flexible enough to bend around small objects, such as the 1mm-thick edge of a glass slide, as shown here. Credit: Juho Kim, et al/ APL

The flexible photovoltaics, made by researchers in South Korea, could power wearable electronics.

Scientists in South Korea have made ultra-thin photovoltaics flexible enough to wrap around the average pencil. The bendy solar cells could power wearable electronics like fitness trackers and smart glasses. The researchers report the results in the journal Applied Physics Letters, from AIP Publishing.

Thin materials flex more easily than thick ones — think a piece of paper versus a cardboard shipping box. The reason for the difference: The stress in a material while it’s being bent increases farther out from the central plane. Because thick sheets have more material farther out they are harder to bend.

“Our photovoltaic is about 1 micrometer thick,” said Jongho Lee, an engineer at the Gwangju Institute of Science and Technology in South Korea. One micrometer is much thinner than an average human hair. Standard photovoltaics are usually hundreds of times thicker, and even most other thin photovoltaics are 2 to 4 times thicker.

The researchers made the ultra-thin solar cells from the semiconductor gallium arsenide. They stamped the cells directly onto a flexible substrate without using an adhesive that would add to the material’s thickness. The cells were then “cold welded” to the electrode on the substrate by applying pressure at 170 degrees Celcius and melting a top layer of material called photoresist that acted as a temporary adhesive. The photoresist was later peeled away, leaving the direct metal to metal bond.

The metal bottom layer also served as a reflector to direct stray photons back to the solar cells. The researchers tested the efficiency of the device at converting sunlight to electricity and found that it was comparable to similar thicker photovoltaics. They performed bending tests and found the cells could wrap around a radius as small as 1.4 millimeters.

The team also performed numerical analysis of the cells, finding that they experience one-fourth the amount of strain of similar cells that are 3.5 micrometers thick.

“The thinner cells are less fragile under bending, but perform similarly or even slightly better,” Lee said.

A few other groups have reported solar cells with thicknesses of around 1 micrometer, but have produced the cells in different ways, for example by removing the whole substract by etching.

By transfer printing instead of etching, the new method developed by Lee and his colleagues may be used to make very flexible photovoltaics with a smaller amount of materials.

The thin cells can be integrated onto glasses frames or fabric and might power the next wave of wearable electronics, Lee said.


Solar Impulse 2 Completes First Ever Solar-Powered Atlantic Flight

Image Courtesy:

By: James Vincent

Solar Impulse 2 has successfully crossed the Atlantic — the first journey of its kind made by a solar-powered plane. The experimental aircraft set off from New York on Monday and landed this morning in Seville, Spain.

The four-day crossing is one of the most difficult sections in the aircraft’s round-the-world flight. The journey started in March 2015 in Abu Dhabi, and last year, the Solar Impulse 2 flew eight stages of its trip — including a record-breaking four-day, 21-hour leg from Japan to Hawaii. However, the craft was forced to wait out the winter on the Pacific island, spending 10 months in a hangar as repairs were carried out and the crew waited for optimum solar conditions.

The Solar Impulse 2 is no heavier than a car, but has a wingspan of 72 meters — exceeding that of a Boeing 747. It’s covered in 17,000 photovoltaic cells which power its motors and charge its batteries during the day, continuing to power the craft at night. The Solar Impulse can only carry a single passenger in its unheated, unpressurized cabin, and typically flies at speeds of around 30 mph (that’s 18 times slower than a regular airplane). However, the plane could hypothetically fly perpetually, and the time it spends airborne is constrained primarily by the pilot’s endurance.

Two pilots — Bertrand Piccard and Andre Borschberg — have managed alternate legs of the aircraft’s round-the-world journey. The aim of the Solar Impulse 2, they say, is not to provide a template for future airplanes, but to show the potential of clean, solar energy.

“The Atlantic is the symbolic part of the flight,” Piccard told The Guardian this morning, a few hours before landing in Spain. “It is symbolic because all the means of transportation have always tried to cross the Atlantic, the first steamboats, the first aeroplane, the first balloons, the first airships and, today, it is the first solar-powered aeroplane.”

Piccard said that during his Atlantic crossing he saw whales breaching the water and an iceberg floating south away from the Arctic. “Every minute is a minute of suspense, a minute of challenge, and the fact I can stay [airborne] without fuel or pollution for four days and four nights is something so new,” he said. “I have the impression I am in a science fiction story and it’s like I am already in the future. And then I look outside and I say, well it’s not the future, it’s now.”

After Seville, the Solar Impulse 2 will fly on to Abu Dhabi, with this last section of its flight split into two or three legs. Greece and Egypt have been highlighted as possible pit-stops, but as with previous legs, this final journey will depend on the weather.


Low-tech Solar Tent Boosts Malawi’s Dried Fish Industry

Fishing communities in Malawi are getting higher prices for their dried fish thanks to simple solar drying technology.

By: Charles Mkoka

Fishing communities in Malawi are getting higher prices for their dried fish thanks to simple solar drying technology

A project to provide fishing communities around Lake Malawi with a cheap and effective way to dry their catch is boosting earnings and improving lives.

Made from a polythene sheet and a simple wooden frame, the drying tents have been designed to trap warm air inside and dry the fish faster, even during rainy weather.

“Processers and mongers involved in the fish business will profit a lot,” Alexandra Kefi, Project Leader for Cultivate Africa’s Future, told Al Jazeera.

“Catches lost in the course of processing will be greatly minimised. This means there will be more money from the same commodity and quantities.”

Researchers estimate that for every 10 fish caught, four are spoiled and their value lost before they can be sold, largely because they rot during the drying process.

Processers welcome the innovation

For those making their living from selling dried fish, such as Stevina Chitedze from Mchenga Njala village in Zomba, the solar tent has resulted in cleaner and better-quality fish, which fetch higher prices and have a longer shelf life.

“This innovation provides a more conducive environment for drying fish compared to open fish drying. Open drying exposes fish to dust, house flies and poor sanitation,” Chitedze told Al Jazeera.

Before using the solar tents, the fish were dried in the open on wire racks.

During the rainy season they would often spoil before being properly dried, forcing them to be thrown out or reducing the prices they fetch at market.

“As a result of the high-quality fish products produced from this innovation, fish processors are now capable of supplying high protein-rich food to orphanages, secondary schools and shops within the communities,” Hamisa Nyapesa, from the project Nsomba Nchuma (Wealth in Fish), told Al Jazeera.

Despite dwindling fish stocks in Lake Malawi, dried fish remains a primary source of protein for many people in the region and contributes about 4 percent of the country‘s GDP.

The industry employs more than 50,000 fishermen and more than 35,000 people are involved in related industries; fish processing, fish marketing, net-making and boat building.

Stopping deforestation

The low-tech solar tents are having another unexpected effect on the areas where they have been built.

By drying the fish using the sun’s energy, there is now no need to cut down trees which were formerly used to smoke the fish.

“Solar is a renewable energy and the fact that it is reducing deforestation, this is good initiative,” Cullen Kamanga, a biologist who graduated from the University of Malawi, told Al Jazeera.

“This means that forest resources will be spared.”

Kamanga says the solar tents will help producers to improve the quality of their dried fish, but they must also strive to ensure their finished product is consistent.

“Having fragmented fishermen producing fish will most likely lead to varying qualities among the finished products,” he said.

The project, which also operates in Zambia, is funded by Canada’s International Development Research Centre and the Australian Centre for International Agriculture Research.

It is continuing to modify the design of the drying tent, to ensure that it delivers the right balance of ventilation and warmth.

Once the design is finalised the project plans to roll it out to more communities in eastern and central Malawi.



Engineer Discovers Light can Stamp out Defects in Semiconductors for Better Solar Panels and LED Bulbs

University of Utah materials science and engineering associate professor Mike Scarpulla stands next to a solar panel made of the compound semiconductor, cadmium telluride. Scarpulla along with Kirstin Alberi of the National Renewable Energy Laboratory have developed a theory that adding light during the manufacturing of semiconductors can reduce defects in the materials, leading to more efficient solar cells and better LEDs. Credit: University of Utah College of Engineering

University of Utah materials science and engineering associate professor Mike Scarpulla wants to shed light on semiconductors — literally.

Scarpulla and senior scientist Kirstin Alberi of the National Renewable Energy Laboratory in Golden, Colorado, have developed a theory that adding light during the manufacturing of semiconductors — the materials that make up the essential parts of computer chips, solar cells and light emitting diodes (LEDs) — can reduce defects and potentially make more efficient solar cells or brighter LEDs. The role of light in semiconductor manufacturing may help explain many puzzling differences between processing methods as well as unlock the potential of materials that could not be used previously.

Scarpulla and Alberi reported their findings in a paper titled “Suppression of Compensating Native Defect Formation During Semiconductor Processing Via Excess Carriers,” published June 16 in the journal, Scientific Reports. The research was funded by grants from the U.S. Department of Energy Office of Basic Energy Sciences.

Semiconductors are pure materials used to produce electronic components such as computer chips, solar cells, radios used in cellphones or LEDs. The theory developed by Scarpulla and Alberi applies to all semiconductors but is most exciting for compound semiconductors — such as gallium arsenide (GaAs), cadmium telluride (CdTe), or gallium nitride (GaN) — that are produced by combining two or more elements from the periodic table. GaAs is used in microwave radios in cellphones, CdTe in solar panels, and GaN in LED light bulbs.

The fact that compound semiconductors require more than one chemical element make them susceptible to defects in the material at an atomic scale, says Scarpulla, who also is a University of Utah electrical and computer engineering associate professor.

“Defects produce lots of effects like difficulty in controlling the conductivity of the material, difficulty in being able to turn sunlight into electricity efficiently in the case of solar cells or difficulty in emitting light efficiently in the case of LEDs,” he says.

For nearly a century, researchers have usually assumed that the numbers of these defects in semiconductors were uniquely defined by the temperature and pressure during processing. “We worked out a complete theory that couples light into that problem,” Scarpulla says.

The team discovered that if you add light while firing the material in a furnace at high temperatures, the light generates extra electrons that can change the composition of the material.

“We ran simulations of what happens,” Scarpulla says. “If you put a piece of a semiconductor in a furnace in the dark, you would get one set of properties from it. But when you shine light on it in the furnace, it turns out you suppress these more problematic defects. We think it may allow us to get around some tricky problems with certain materials that have prevented their use for decades. The exciting work is in the future though — actually testing these predictions to make better devices.”

The team is working to apply their theory to as many semiconductors as possible and testing the real world results. For example, the team believes this could improve the efficiency of solar panels that use thin films of cadmium telluride and even those made from silicon.

“It’s really cool to be working on this fundamental problem in semiconductors,” says Scarpulla. “Most of the ideas were worked out decades ago, so it is really exciting to be able to make a contribution to something fundamental. It feels like we have shined light onto a new path and we don’t know how far it will take us.”