Solar charge controller to improve efficiency of solar panels

charge controller

New controller for solar panels

The simplest and easiest way to charge a battery with a solar panel is to connect the panel directly to the battery. Assuming the panel has a diode to prevent energy from flowing through it from the battery when there’s no sunlight. This is fairly common but not very efficient. Debasish Dutta has built a charge controller that addresses the inefficiencies of such a system though, and was able to implement maximum power point tracking using an Arduino.

Maximum power point tracking (MPPT) is a method that uses PWM and a special DC-DC converter to match the impedance of the solar panel to the battery. This means that more energy can be harvested from the panel than would otherwise be available. The circuit is placed in between the panel and the battery and regulates the output voltage of the panel so it matches the voltage on the battery more closely. [Debasish] reports that an efficiency gain of 30-40% can be made with this particular design.

According to Hackday, this device has a few bells and whistles as well, including the ability to log data over WiFi, an LCD display to report the status of the panel, battery, and controller, and can charge USB devices. This would be a great addition to any solar installation, especially if you’ve built one into your truck.

This is [Debasish]’s second entry to The Hackaday Prize. We covered his first one a few days ago. That means only one thing: start a project and start documenting it on hackaday.io

Solar Shirt: the phone charger you can wear

solar shirt

The solar shirt. Photo: Holst Centre

Ever had the frustration of your phone, camera or GPS battery going flat when you’re out and about? That could soon be a thing of the past thanks to the Solar Shirt – the follow-up project after Wearable Solar. Created in collaboration by Holst Centre, TNO and renowned fashion designer Pauline van Dongen, the shirt brings the worlds of high tech and high-street fashion together.

It combines solar panels and flexible electronics into an attractive, off-the-peg T-shirt for everyday wear that can charge your smartphone or other portable devices.

According to Printed Electronics World, the Solar Shirt generates power from 120 thin-film solar cells integrated into the fabric itself. In bright sunlight, it produces around 1 W of electricity – enough to charge a typical phone in a few hours. Indoors, the shirt generates enough power to keep a battery charged – so your phone or other device is always ready when you need it.

The shirt can charge smartphones, MP3 players, cameras, GPS systems and other USB-compatible handheld or portable devices. And if all your devices are charged, the electricity can be stored in the shirt’s battery pack for later use.

The solar cells are combined into standardized functional modules using Holst Centre’s vast solar cell know-how developed within the Solliance alliance and its stretchable electronics technology for integrating electronics into fabrics. This technology is part of a research program on wearable applications that integrates functionalities ranging from lighting (LED/OLED), energy harvesting (PV), sensors and displays, in textile or other flexible materials.

The solar cell modules can be mass-manufactured in a cost effective way by Roll to Roll compatible technologies and then incorporated into the fabric using familiar industrial “iron-on” techniques before the garment is stitched. Designers and garment manufacturers can arrange the modules as they like, giving them complete freedom to create their own unique designs,” says Holst Centre’s Managing Director Ton van Mol.

The Solar Shirt design was created by fashion designer Pauline van Dongen, a pioneer in the field of wearable technology garments. “Wearing solar cells lets us harness the sun’s potential energy and become a power source ourselves. As a designer, I’m excited by how solar cells can add to the esthetic of a garment. To date, all attempts to combine solar technology and fashion had focused on one-off haute couture designs.With Holst Centre’s technology, we were able to seamlessly integrate the technology and the design so they mutually inform each other – advancing the concept and value of fashion. We’ve taken solar fashion from the catwalk to the high street, with an attractive yet practical garment that people could wear every day,” she says.

“Our technology enables extremely thin electronics that are stretchable, flexible and washable. It can be integrated into fabrics using standard high-volume techniques that are well known in the textile industry. The maturity of the technology means textile manufactures could bring functional fabrics to market in a matter of months using existing production facilities. Pauline is one of the leading names in wearable technology, and her design shows how technology and fashion can complement each other to create desirable clothing that has a function,” adds Holst Centre’s Margreet de Kok.

Natural silk can boost the performance of lithium-ion batteries

natural silk can boost lithium-ion batteries

Natural silk to improve lithium-ion batteries

A green material derived from natural silk can boost the performance of lithium-ion batteries used in portable gadgets and electric cars, scientists say.

Carbon is a key component in commercial lithium-ion energy storage devices including batteries and supercapacitors.

Most commonly, graphite fills that role, but it has a limited energy capacity, researchers said.

To improve the energy storage, manufacturers are looking for an alternative material to replace graphite.

According to Tech First Post, Chuanbao Cao and colleagues at the Beijing Institute of Technology wanted to see if they could develop such a material using a sustainable source.

The researchers found a way to process natural silk to create carbon-based nanosheets that could potentially be used in energy storage devices.

Their material stores five times more lithium than graphite can – a capacity that is critical to improving battery performance.

It also worked for over 10,000 cycles with only a 9 per cent loss in stability.

The researchers successfully incorporated their material in prototype batteries and supercapacitors in a one-step method that could easily be scaled up.

The study is published in the journal ACS Nano.

Solar panels stolen from Gloucestershire energy farm may be sold on

solar farm

Thousands of pounds of solar panels stolen from Cambridge farm

Police have urged people in Gloucestershire to be aware of stolen solar panels being sold door-to-door. Panels worth several thousand pounds were taken from a Gloucestershire farm earlier this week.

According to SouthWest Business, the theft happened in Bristol Road, Cambridge, between 9pm on Monday and 9am on Tuesday.

The thieves gained entry to the site by removing a stile and part of a fence.

Once on the site the raiders removed six or seven pallet-loads of solar panels worth several thousand pounds from a solar panel farm.

Police believe the suspects are now attempting to offload them door-to-door as at around 2.10pm on Tuesday, two men knocked at the door of a number of houses on Upton’s Gardens in Whitminster trying to sell solar panels to the occupants.

Police believe that the two incidents are linked.

Kim Mowday, harm reduction advisor for Gloucestershire police said: “Always be very cautious when buying anything from salespeople turning up at your door unannounced.

“There are lots of reasons why it is dangerous to purchase anything from someone you don’t know or aren’t expecting.

“At best you could be sold faulty items which could leave you significantly out of pocket. At worst you could be breaking the law by handling stolen goods.”

The householder in this instance did the right thing by contacting police immediately, he said.

“If you experience something similar we would advise you to do the same by calling 101.”

The first offender is described as white and around 30-35 years-old.

He was of slim build, with reddish coloured hair and around 5ft 10ins tall.

He was scruffy looking, unshaven and was wearing a navy blue v-neck top, light shirt and baggy, loose trousers.

The second offender was also described as white but smarter in appearance. He was around 5ft 9ins tall, of slim build with dark hair.

He was wearing a grey v-neck jumper and possibly had a Welsh accent.

Anyone who may have any information on either of these incidents is asked to contact Glouces

Unprecedented solar power boom in U.S.

solar power in U.S.

Solar boom in U.S.

U.S. solar power grew by 6.2 gigawatts in 2014, a 30 percent increase over the previous year and representing nearly $18 billion in new investment, according to data released by the Solar Energy Industries Association and GTM Research.

According to Scientific American, the new power systems, comprising tens of thousands of photovoltaic (PV) arrays for homes, schools, businesses and utilities, as well as a handful of large concentrated solar power facilities in places like the Mojave Desert, raised the United States’ profile as one of the world’s leading adopters of solar power, officials said.

But the future for U.S. solar isn’t without its bumps.

New installations of nonresidential solar panels, while accounting for more than 1 GW of power, shrank by 6 percent year over year, a condition caused by a variety of factors “ranging from tight economics to difficulty financing small commercial installations,” GTM analysts said in their latest “U.S. Solar Market Insight Report.”

Meanwhile, the industry’s primary federal support—the 33 percent investment tax credit (ITC)—is set to expire at the end of 2016, effectively shifting the cost burden of solar fully to developers and consumers of clean power. And as with other renewable energy resources, solar’s future will be affected by the status of state renewable portfolio standards that direct rate-based utilities to produce or acquire a percentage of their power sales from clean energy resources.

Yet, even with those caveats, industry officials and analysts forecast a continued boom in U.S. solar markets over the near term, with a projected 31 percent growth target for 2015. The growth will be fueled by falling costs for solar panels and modules, business model innovation that allows for more flexibility in ownership, favorable political and regulatory environments, and increased access to low-cost capital.

Solar beats wind and coal on key metric
Shayle Kann, senior vice president at GTM Research, noted that in just five years, the U.S. PV market—which does not include concentrated solar plants—has witnessed a fourfold expansion, from an estimated $3 billion in 2009 to $13.4 billion last year.

Moreover, solar accounted for 32 percent of the nation’s new generating capacity in 2014, beating out both wind energy and coal for the second consecutive year. Only natural gas constituted a greater share of new generating capacity, according to the report.

“From a high-level national perspective, the market has continued to see really impressive growth,” both in established solar markets like California and Arizona and in regions where solar is a relative newcomer, such as in Virginia, the Carolinas, Georgia and Louisiana.

Some of the growth, especially in emerging solar states, was attributable to state incentives for residential and commercial solar, the growing popularity of third-party leases offered by firms like SolarCity and Sunrun, and a desire on the part of large utilities to diversify their fuel portfolios to include renewable energy.

Cory Honeyman, a GTM solar analyst and lead author of the 2014 market report, further noted that “2014 was the year where the concept of retail rate parity became something that extended beyond California to a growing number of other markets.”

For example, North Carolina for 2014 was the nation’s No. 2 solar state by installations behind California, with 397 megawatts of new solar power coming online. It was followed by Nevada, Massachusetts, Arizona and New Jersey, all of which have well-established solar markets.

Other states rising in the solar ranks include New Mexico, Missouri and Maryland. New Mexico for the first time became a top 10 state for solar development thanks to its 88 MW gain in solar capacity last year.

New York, Texas and Hawaii also each added more than 100 MW of solar capacity in 2014, securing their spots among the nation’s solar leaders. Elsewhere in the Southeast, Georgia and Tennessee saw marked increases in utility-scale solar, while Louisiana and South Carolina experienced sustained growth in the residential solar sector, according to GTM.

The U.S. residential sector added 1.2 GW of capacity in 2014, marking its first time surpassing 1 GW, according to GTM. Residential PV continues to be the fastest-growing market segment in the U.S. solar sector, riding three consecutive years of 50 percent or higher annual growth.

The utility sector also remains very strong, adding nearly 1 GW annually over the past several years. In 2014, 3.9 GW of utility-scale PV projects came online in the United States, with an additional 14 GW of projects under contract.

“Today the U.S. solar industry has more employees than tech giants Google, Apple, Facebook and Twitter combined,” Rhone Resch, SEIA’s president and chief executive officer, said in a statement. That success, he added, has come in part from the 9-year-old investment tax credit for solar power.

“We now have 20 gigawatts of installed solar capacity—enough to power 4 million U.S. homes—and we’re helping to reduce harmful carbon emissions by 20 million metric tons a year,” Resch said. “By any measurement, the ITC has been a huge success for both our economy and environment.”

Solar-powered space camera detects skin cancer on Earth

solar-powered space camera

High-tech camera detects skin cancer earlier

Space-based cameras originally designed to combat famine in Africa by monitoring vegetation are being adapted to help detect diseases such as skin cancer.

According to Red Orbit, the Proba-V vegetation-scanning satellite’s high-speed camera and digital infrared sensors can be used with a standard medical scanner, allowing doctors to look deeper into human skin tissue and detect skin diseases earlier than ever before.

It is one of several non-space applications for the technology currently under consideration, the agency explained. Other possible uses include improving solar cell production and spotting items that are defective while they’re still on the assembly line.

The Proba-V camera, which was developed for the ESA by a Belgian firm known as Xenics, is able to see light that we cannot by looking at in the shortwave infrared range. It also has a unique wide field of view that can create a new image of out planet’s flora every 48 hours.

“To humans, two green trees could look similar. But with this camera, we might detect that one is growing well and the other is unhealthy,” ESA’s Michael Francois explained.

Using its sensor, the Proba-V can monitor the Amazon rainforest or help African farmers predict crop yields.

“Based on the experience of preceding years, you can determine whether crop growth is on schedule or behind, and you can get early information on whether there will be sufficient food,” noted Koen van der Zanden from Xenics.

“The high-speed resolution of our ‘line-scan’ cameras makes them ideal for detecting hidden defects on fast-moving production lines, such as bottle manufacturing or sorting different types of plastics for recycling – all of which look similar to the human eye,” Koen added. “The items are moving fast, just like Earth spins below the satellite, so by scanning one complete line at a time we can quickly cover the whole area.”

The Proba-V camera is capable of generating a 2250 kilometer wide picture of the land with each sweep of its 3072-pixel line sensor, the ESA said. Unlike conventional rectangular detectors such as those used in off-the-shelf digital cameras, however, the satellite’s sensor captures information one line at a time and does so with incredible speed.

As the target moves past, Proba-V creates a complete image, which increases the efficiency of imaging rapid objects on production lines. That ability, combined with its capability to “see the unseeable,” makes commercialization of the technology attractive and feasible.

Skin diseases and solar panels

Xenics is currently adapting their invention for use by doctors, with the idea that their technology will be able to improve a doctor’s ability to diagnose skin diseases. While scanners have been able to provide detailed cross-section images of living tissue for more than two decades, their space camera’s sensitivity at some wavelengths allow it to look deeper in search of diseases.

“It may still be a few years away but once our sensors start helping doctors to diagnose skin diseases and catch them at earlier stages, then we can all feel doubly proud of this spin-off from space,” Koen explained.

In addition, this capability allows the device to quickly spot defects on solar panels. When those panels are illuminated, the camera can gauge their efficiency quickly by spotting any dulling of the weak glow the cells emit when they absorb light, the ESA explained.

“The transfer of this specially developed camera technology for ESA’s Proba-V has positioned a European company in a leading position globally for linear shortwave infrared sensor technology,” added Sam Waes from the ESA’s Belgian technology broker, Verhaert. “It is an excellent demonstration of how investments in our space programs help European industry benefit from space technology spin-offs.”

The first solar-powered round-the-World journey has begun

Solar Impulse 2

Solar Impulse plane begins epic global flight

An historic attempt to fly around the world in a solar-powered aircraft the weight of a minivan began Monday as the plane took off from Abu Dhabi on the first leg of its record-breaking journey.

According to The Washington Post, the Swiss-made, single-seat plane left Abu Dhabi’s Al Bateen Executive Airport just as the sun was rising. The plane, incredibly light but with a wing-span longer than that of a 747 jet, runs only on solar power. Its wings carry just over 17,000 solar cells that transfer solar energy to four electrical motors that then power the plane’s propellers.

 Electric bikes followed the plane, the Solar Impulse 2, as it taxied to take off, to prevent the wings from touching the runway, the British Broadcasting Corporation reported.

 Solar Impulse founder Andre Borschberg flew the plane on the first leg of its 21,700-mile journey around the world. He will trade off with fellow Swiss co-founder Bertrand Piccard during layovers.

 “After 16 years of a dream, and 12 years of hard work, we hope it will work,” an excited Bertrand told the BBC after the plane took off.

 Some legs of the 25-day, five-month global journey will mean five full days and nights of flying solo, such as when it crosses both the Pacific and Atlantic oceans. It is due back in Abu Dhabi in late July or August.

 The plane will stop at various locations around the world — for the pilots to rest and do maintenance — but also, more importantly, to spread the message about clean, renewable technologies.

 The cockpit of the plane, about the size of a telephone booth, is so cramped it holds only one person. The pilots will not be able to stand while flying, however, but the single seat reclines for stretching and its cushion can be removed to access a toilet.

“We never feel alone in the cockpit, though,” Bertrand told the BBC. He said millions of people around the world were behind the prototype effort to find a more sustainable and cleaner alternative to fossil fuel-powered aircraft. He pointed out that flight pioneer Charles Lindbergh also flew in a small cockpit, whereas now jets can hold hundreds of passengers.

The plane weighs just over 5,000 pounds, about as much as either a minivan or a mid-sized truck. An empty Boeing 747 jet weighs about 400,000 pounds.The solar cells line the top of the aircraft’s long wings and energy-dense lithium-ion batteries sustain it during night-time flying.

On its first leg, the plane will head to Muscat, Oman, a journey that will take it about 10 hours. A typical passenger jet would take just one hour to make the same journey. The best speed for the plane is about 28 mph, the pilots told the Associated Press news agency. The slow speed of the plane means the journey’s legs will take several days and nights of non-stop flying.

Borschberg has been practicing yoga and Piccard self-hypnosis to get ready for the historic endeavor, the AP reported. They aim to rest a maximum of 20 minutes straight, repeating the naps 12 times over a 24-hour period — similar to how a lone round-the-world yachtsman catches small periods of sleep.

Goggles worn over the pilot’s eyes will flash lights to wake him up, the AP said, and armbands placed underneath their flying suits will buzz if the plane isn’t flying level.

The plane will reach an altitude of around 28,000 feet during daytime hours to catch the sun’s rays. At night, when flying over oceans, it will fall to around 5,000 feet.

After two stops in India, the plane will head to China, where it will stay for a month until the days are longer to catch more of the sun’s energy. It also plans stops in Myanmar, Hawaii, Arizona and New York’s John F. Kennedy International Airport. The path across the Atlantic will depend on the weather and could include stops in southern Europe or Morocco.

Those interested can follow the aircraft on Solar Impulse’s Web site, tracking its battery status, energy consumption, location and flight path, as well as how much the pilot has slept and how much food and water he has left. There is also a live feed of the plane’s Monaco-based control room with occasional footage from the cockpit.

Solar Impulse supporter Prince Albert of Monaco attended the Monday take-off. Other sponsors include Masdar, Abu Dhabi’s clean-energy company, Omega, Google and Moet Hennessey, among others, the AP reported.

“Now the adventure has started,” Piccard told the news agency at take-off.

Traffic cops in Kinshasa? No, they now have solar-powered robocops!

solar-powered robocop

Solar-powered robocops in Kinshasa. Foto: AFP

In Kinshasa, the teeming capital of the Democratic Republic of Congo, where drivers often flout traffic rules, five chunky, arm-waving robots equipped with cameras, lights and solar panels have been set up to watch over the roads.

According to South China Morning Post, the solar-powered aluminium robots are huge, towering over the jammed streets, as cars and motorcycles jostle for road room, their horns blasting.

Each hand on the odd-looking machines – built to withstand the year-round tropical climate – is fitted with green and red lights that regulate the flow of traffic in the sprawling city of nine million.

The robots are also equipped with rotating chests and surveillance cameras that send real-time images to the police station.

Although the humanoids look more like giant toys than real policemen, motorists have given them a thumbs-up.

“There are certain drivers who don’t respect the traffic police. But with the robot it will be different. We should respect the robot,” taxi driver Poro Zidane said.

“We’re very happy about it,” he said, his taxi packed with passengers as drivers around him honked their horns in a desperate bid to cut through the traffic jam.

Of the five robots set up across the capital, two have been regulating traffic since 2013.

On Tuesday, three new and improved robots developed by a Congolese association of women engineers were set up.

The newcomers even have names: Tamuke, Mwaluke and Kisanga. Each cost US$27,500.

Therese Izay, president of Women’s Technology, the group behind the robots, believes the invention will help make it far more difficult for motorists to get away with traffic violations.

“In our city, someone can commit an offence and run away, and say that no one saw him. But now, day or night, we’ll be able to see him in real time and he will pay his fine like in all the serious countries of the world,” she said.

But Kinshasa governor Andre Kimbuta said that while the machines could regulate traffic, they were no match for real human policemen who could chase motorists who jump red lights and raise civic awareness.

“We should congratulate our Congolese engineers, but policemen also need to do their job,” the civic leader said.

Australian-first floating solar plant under construction in South

 floating solar farm

PHOTO: Solar panels will be floated at the wastewater facility at Jamestown similar to a current project in France.

An Australian-first floating solar power plant it may be operational in South Australia by early April, with construction about to begin.

According to ABC News, the plant will float on a wastewater treatment facility in Jamestown in the state’s mid north.

Felicia Whiting of Infratech Industries said the plant was designed so that much of the construction could be carried out offsite and slotted together at the facility.

“We should see some plant on the site within about two weeks,” Ms Whiting said.

She also explained that as the solar panels were floating they would be kept cool by the water mass, making them about 57 per cent more efficient than land-based solar panels.

“It prevents water evaporation up to 90 per cent of the surface area covered, and for dry states and dry climates that’s a big water saving measure,” Ms Whiting said.

“It prevents the outbreak of blue-green algae by keeping the surface water cool, which is for treated wastewater an issue in water quality.

“By preventing photosynthesis, the energy from the sun goes into the panel rather than into the water.”

Jamestown solar farm to showcase technology

Infratech has developed floating solar power plants in countries such as France and South Korea, but the company had seen them as test sites for the new and improved model planned for South Australia.

“The plants that we had operating overseas were really behind the meter and not at the utility level and certainly didn’t have some of the sophistication,” Ms Whiting said.

The South Australian plant was expected to produce not only enough energy to power its co-located wastewater treatment facility, but have excess power flow-on to the township of Jamestown.

“The water treatment plants are heavy uses of power for the actual water treatments and pumping,” Ms Whiting said.

“Quite sustainably, with no additional use of land, we can use the water surface to power the water treatment facility.

“In addition to that, because we’re so efficient, we’re able to export power to the township.”

Ms Whiting said that once operational, the plant would become Infratech’s showpiece for export around the world.

“We’ve invested our whole research and development program in this technology over the past two years in South Australia,” she said.

“We have other councils waiting to have a look at this and see how it might be adapted to a water basin or a community wastewater management scheme.

“We are using Australian engineering and it’s an Australian supply chain – that will be taken internationally.”

Google aims to change mobile business with solar-powered internet drones

Google solar-powered drone

Google is preparing to conduct test flights of its solar-powered internet drones in the next few months

Google is working on Project Titan programme, which aims to provide internet services with solar-powered drones to four billion people in rural and remote areas who have no internet access.

Speaking at the Mobile World Congress in Barcelona, Spain, Google senior vice-president Sundar Pichai said the lightweight drones will hover over certain areas, and serve as remote satellites to provide web connectivity.

While Project Titan is designed to focus on specific, narrower areas, Google’s Project Loon covers greater regions using balloons, which will act as floating cell towers.

“Google is working on Project Titan programme, which aims to provide internet services to four billion people in rural and remote areas who have no internet access.”

According to Aerospace Technology, Google has been seeking to strengthen its capabilities in the aerospace segment, and leverage the expertise to expand web access to isolated parts of the world.

In line with these plans, the company acquired Skybox Imaging and Titan Aerospace in 2014.

Titan Aerospace is working on solar-powered internet drones, which can fly at an altitude of 65,000ft for up to five years, and offer data speeds of up to one gigabit a second.

Google is also working on Project Wing to develop drones that could be used for goods deliveries.

Earlier this year, the company participated in SpaceX’s $1bn financing round and acquired a stake of less than 10% with Fidelity Investments.