April 2015 – Page 2 – Solar Magazine

Study says abandoned coal mines can produce clean energy

Abandoned coal mines to produce renewable energy. Image via abandonedplaces.livejournal.com

New technology could heat 45,000 homes in the UK, says team at Nottingham Trent University. In a novel example of the transition from high to low carbon infrastructure, researchers in Nottingham have discovered how abandoned coal mines could produce renewable heating for tens of thousands of homes and offices in the UK.

According to Business Green, as part of a two-year project, researchers at Nottingham Trent University worked with renewable energy firm Alkane Energy to explore how water at the former Markham Colliery in NortEast Derbyshire could be condensed in a heat pump and fed through a district heating network.

The team took naturally lukewarm water from the mineshaft and pumped it to the surface, where a heat exchanger extracted its thermal energy. The energy was then condensed through a heat pump to increase the temperature further while the water was returned to the mine where it becomes lukewarm again.

The team explored a series of old mines in the UK, which they estimate could provide enough heat for around 45,000 homes.

Professor Amin Al-Habaibeh of Nottingham Trent’s School of Architecture, Design and the Built Environment, who led the study, said he hoped the breakthrough would provide a new lease of life to abandoned mines.

“In a way we may never have previously envisaged, coalmines could once again be used to provide warmth to thousands of homes across the UK,” he said in a statement.

“But the key difference between yesteryear and tomorrow is that we now have the ability to harness their energy potential in a completely sustainable way.”

Alkane says it hopes to use the research findings to support a new business venture. The company already uses gas from disused mines to produce electricity, and it reckons harnessing heat from old mines could provide an additional source of clean energy.

Post-Fukushima Japan turns to wind as solution for energy crisis

Japan turns to wind energy to solve energy crisis

The kamikaze pilots that flew bombing raids and suicide missions against the Allies in World War Two were inspired by a “divine wind” that they believed was keeping their planes aloft in the service of the Japanese Empire. Legend has it that the divine wind from which the word “kamikaze” is translated, referred to a typhoon that saved the Japanese islands from invasion by a Mongol fleet in 1281.

Seventy years after the end of the Second World War, nature continues to exert a powerful influence on the Japanese nation, and we only have to look back four years to see the devastation caused by the Great East Japan Earthquake, as it is known there.

Now, the threat to Japan comes not from outside enemies, but from her own internal weaknesses, particularly the lack of natural resources requiring Japan to either import coal and liquefied natural gas in large quantities, or maintain aging nuclear power plants that remain vulnerable to earthquakes and tsunamis.

According to oilprice.com, in 2015, the wind that once inspired kamikaze pilots is once again being pressed into service, only now the goal is not a wartime victory, but to move Japan a step closer to energy independence.

As a far-flung island nation, Japan appears to be ideally suited to capturing power from the wind. The country has the sixth largest sea surface in the world, including economic zones allowing resource exploitation, and in Japan the wind blows strong especially during typhoon season.

However, up to now, wind power in Japan has been underutilized, particularly compared to solar. While the Japanese photovoltaic market has risen 7-fold, from 1GW in 2010 to almost 7GW in 2013, growth in wind power has underwhelmed.

The country produces less than one percent of its power from wind turbines, and in 2013 Japan installed 100 times more solar power than wind. According to Wind Power Monthly, Japan has just 2.6GW of installed wind capacity, virtually all of it onshore.

The publication notes that Japan’s reluctance to develop offshore wind is down to three factors:

“First, 80% of its offshore resources are in depths greater than 100 meters, far beyond the reach of the conventional fixed-bottom foundations that support the offshore projects on northern Europe’s continental shelf. Second, the climate and conditions – typhoons and tsunamis – present formidable challenges to installation and upkeep of wind turbines. Third, Japan’s powerful maritime logistics and fishing industries have strongly opposed sharing ocean space with wind developers.”

Another factor is Japan’s feed-in tariff requiring electrical utilities to buy renewable energy at set rates. While the tariff has resulted in a big increase in solar panel investment, largely because photovoltaics are relatively easy to install, for wind producers the tariff is less attractive, because high installation costs make small-scale generators unprofitable, according to manufacturers of small wind farms – those whose windmill diameter is less than 7 meters and with generation capacity of 20 kW or lower.

There are encouraging signs however, that Japan’s wind-power industry is starting to blow a lot stronger. Following the Fukushima disaster in 2011, the Japanese government approved a budget of 12.5 billion yen (US$12.2 million) to encourage wind power development, and shortly thereafter, a consortium of 10 companies led by Marubeni Corp began building a floating wind farm offshore of the Fukushima prefecture. The farm, powered by a 2MW turbine, has been generating power since November 2013. A second phase is currently under development to install an additional two 7MW turbines.

Marubeni notes the Fukushima Recovery/Floating Offshore Wind Farm Experimental Project has three themes: “By a team comprising only Japanese members,” “to pioneer Japan’s new international business,” and “to contribute to the recovery of Fukushima.”

Marubeni was also recently selected to construct 145MW of offshore wind capacity in northern Japan by 2021. The project is divided into two wind parks. The first park off the northwestern coast of Honshu will have 13 5MW turbines. A second park, located near Noshiro port, will have 16 turbines also providing 5MW each.

If the planned wind farms off Honshu go ahead as planned, they will mean a huge expansion in wind power for a nation that has until very recently shown little interest in the renewable energy form.

According to the World Nuclear Association Japan’s electricity utilization rate at the end of 2012 was 295GWe for nuclear, compared to 2.5 GWe for wind, 6.6GWe for solar and 0.5GWe geothermal. The rest of Japan’s energy requirements were met from hydro, at 45 GWe, 36 GWe from coal and 47 GWe from natural gas.

The Japan Wind Power Association estimates the country has the potential for 622GW of offshore wind, and 168GW onshore (the association has a goal of 50MW by 2050), however, one must ask to what degree the Japanese citizenry would tolerate such a massive expansion of wind power.

Marubeni’s Fukushima offshore wind project was lauded for its ability to produce utility-scale power with equivalent output to a nuclear reactor, but the project also drew criticism from Japanese fisheries unions who opposed it for its potential to destroy fishing grounds and prevent trawler fishing.

Wind skeptics in Japan also point to delays in setting up an offshore wind tariff, and local opposition to onshore wind – proving that the Japanese are no different from other countries in their NIMBYist attitude to wind farms near homes, schools and businesses.

The Japanese government solved the first problem a year ago with the introduction of a 36-yen-a-kilowatt-hour subsidy for offshore wind, but the NIMBY issue is obviously more intractable and presents a challenge to the further expansion of wind power in Japan, even in rural areas.

A 2013 study by Ryukoku University in Kyoto showed that while over 80 percent of respondents approved of large-scale wind power projects, 69 percent worried about such projects in their neighborhoods.

NIMBYism was likely a key factor in why Japan has moved its wind farms offshore, so it will be interesting to see whether more ocean wind power proceeds unobstructed, or whether industry lobby groups, like the Fukushima fishermen, will lobby to prevent further incursions into traditional Japanese industrial activities.

Turkish farms will use solar power to cover their own electrical demand

Solar power for Turkish agricultural sector

Solar energy is about to power Turkish agricultural sector, which is among the most significant market sectors in the country. In the upcoming period, the most important innovation for the sector will be clean energy produced by solar panels.

According to Daily Sabah Business, the aim is to use solar energy to cover all energy expenses of agricultural lands that are large enough to support it. The devised system is especially advantageous for farmers using well water, since they have to pay high bills for using electrical engines to pump water from the ground.

The cost of this process decreases nearly one-10th and the system also recoups its costs within two years by operating drip irrigation systems.

The Ministry of Energy and Natural Resources, the Ministry of Economy, Ministry of Food, Agriculture and Livestock and the Ministry of Finance are carrying out collaborative work to establish an effective incentive policy on this issue. The fact that the energy surplus obtained from the energy plants will be transferred to the government increases the attractiveness of the project, and the number of Turkish companies specializing in the field is increasing daily.

This paper thin battery will charge your smartphone in 60 seconds

This new graphite battery will charge your smartphone in 60 seconds. Credit: Meng-Chang Lin & Hongjie Dai, Stanford University

Battery life problems are among the most common smartphone affliction. No matter how power efficient the hardware gets, manufacturers end up using all of it and more for improved displays, faster performance, and more features. Now scientists at Stanford University have come up with an ultra-fast-charging paper thin battery that can be produced on a mass scale. Bonus: the battery can charge your smartphone in 60 seconds.

“We have developed a rechargeable aluminum battery that may replace existing storage devices, such as alkaline batteries, which are bad for the environment, and lithium-ion batteries, which occasionally burst into flames,” said Hongjie Dai, professor of chemistry at Stanford, in a statement. “Our new battery won’t catch fire, even if you drill through it.”

According to Extreme Tech, the aluminum-ion battery contains a negatively charged anode and a positively charged graphite cathode. Researchers placed those two inside a flexible polymer-coated pouch with an ionic liquid electrolyte. Aluminum has always been a compelling material for battery design, but it’s been too difficult to work with. It’s inexpensive, not flammable, and could potentially have high capacities. The problem up until this point, the researchers said, is developing the right materials that could repeatedly produce sufficient voltage after multiple cycles of charging and discharging.

Current lithium-ion batteries in smartphones can take several hours to charge. Some manufacturers like Samsung and HTC have developed fast burst modes that give you 25 percent of initial battery life with just 15 minutes of charging, and have also baked in new slow-burn, emergency efficient modes to eke extra time out of the last few percentage points of battery life. But this new aluminum-ion battery prototype has “unprecedented charging times” down to just one minute. Plus, the researchers were able to charge and discharge the battery 7,500 times without loss of capacity, compared with 1,000 cycles or less for today’s packs.

The researchers said that in addition to phone batteries, the aluminum-ion design could also be used to store extra capacity in renewable power grids, and the two-volt output could also be an environmentally replacement for 1.5-volt disposable AA and AAA batteries.

And that’s where the research continues: That voltage, while better than the disposable batteries, is still only about half that what you need for a smartphone. It’s the last major hurdle, after inexpensive materials, safety, ultra-fast charging, and long life cycle. Here’s hoping they nail it, because at this point we’re all sick of having to charge our devices all the time.

Abeer Seikaly’s stunning woven refugee tents powered by the sun

Solar-powered shelters for disaster zones

Award-winning architect and designer Abeer Seikaly has created a practical yet beautiful solution to the need for lightweight, mobile, and structurally sound shelters for disaster zones.

According to inhabitat.com, the Canadian-Jordanian’s Weaving a Home project not only provides flexible, transportable shelter, but also incorporates water collection, solar power generation and solar water heating into the design.

Drawing inspiration from traditional basket weaving techniques and the flexibility of snake skin, the designer uses weatherproof fabric drawn between durable, curved plastic tubing. This creates a structurally sound tent that can handle both compression and tension loads.

The double-layered fabric tent skins are also hollow, allowing for weatherproof entrances and for water piping and electrical cables to run between the layers. While the design is scalable, the models shown are five meters in diameter and 2.4 meters high.

Solar-powered woven refugee tents. Image via designboom.com

Each tent has its own water collection system, utilizing the natural channels formed by the skin to direct water to the storage point. By using a fabric with strong thermal properties, the tents can also convert solar radiation into power and heat collected water for showering. The strength of convection can also be used to draw fresh water into the heating system from an external source. The flexible design of the tents allow for openings to be made wherever they are needed to allow hot air out and to catch any cross-breezes. The tents also seal up tight in case of wet weather or cold conditions.

Seikaly states: “‘Weaving a Home’ reexamines the traditional architectural concept of tent shelters by creating a technical, structural fabric that expands to enclose and contracts for mobility while providing the comforts of contemporary life (heat, running water, electricity, storage, etc.)” The honeycomb-like design folds up neatly when not in use to allow for easy transportation to wherever the tents are needed. The project was a winning entry in the 2013 Lexus Design Awards.

Delhi University students show us how Metro trains can produce wind energy

The team, involving ten students of Physics and Computer Science departments, proposed setting up a turbine at an underground metro station to check if it can be successful in harnessing the wind.

Delhi University students found an innovative way of harnessing wind energy churned out by Metro trains to generate electricity.

According to IBN Live, the project, undertaken by Kalindi College, has also got the backing of Delhi Metro Rail Corporation (DMRC), which allowed the students to install a turbine on trial basis at one of the underground metro stations.

“While standing at a metro station one day, the students realised that the wind energy produced in the tunnel by these fast moving trains gets wasted, and they decided to find out how it can be harnessed,” says Dr Punita Verma, Principal Investigator of the project.

The team, involving ten students of Physics and Computer Science departments, proposed setting up a turbine at an underground metro station to check if it can be successful in harnessing the wind. DMRC officials found the project interesting and gave the nod to install a turbine at Chandni Chowk metro station.

“Without obstructing the operation, safety and security of Metro services, it was decided to put up turbine along the underground tracks at the mouth of tunnel where the maximum wind velocity available is 6.5 m/s.

“In the first phase, we installed a three-blade turbine and later a five-blade light rotor turbine with a cut-in speed of less than 1.5m/s. We connected it to a battery and measured the power it generates. We also discovered that different stations have different construction and the same turbines cannot be used at all the metro stations,” Verma said.

The project, which has was started by a different group of students in 2013, has received a grant of Rs 15 lakh from the university. While the first phase involved the research work, the DMRC engineers were later roped in to test the feasibility, who have asked the team to develop the concept further.

“We are now working on different designs of the turbines whose size, shape and orientation will be customised according to the wind velocity and frequency of trains at different stations. Once the design is approved by DMRC, turbine firms will be approached to make these turbines,” Verma says.

Adding clean energy to power grid requires flexibility

Renewable energy and the power grid

Solar panels, wind turbines, electric vehicles and other green power sources are proliferating rapidly, but their reliable integration into the existing electric grid is another story.

According to http phys.org, a study led by Eilyan Bitar, assistant professor of electrical and computer engineering, offers a comprehensive reimagining of the power grid that involves the coordinated integration of small-scale distributed energy resources.

The study, commissioned by the Power Systems Engineering Research Center (PSERC), asserts that the proliferation of renewable energy must happen at the periphery of the power grid, which will enable the local generation of power that can be coordinated with flexible demand.

Bitar’s study outlines a new architecture to enable what he calls a grid with an intelligent periphery – a version of the so-called smart grid – along with coordination strategies and mathematical models to simulate how such a reorganized grid would work.

“The uncoordinated proliferation of distributed energy resources will wreak havoc at scale,” Bitar said. “Certain components of the legacy power system will fail; the existing distribution infrastructure isn’t equipped to accommodate, for instance, a large number of electric vehicles plugging into the grid at the same time under the same transformer … but, imagine taking all these new resources and coordinating their control.”

The way the power grid works now, large plants deliver power to substations, where electricity is provided on demand to homes. The fluctuating electric loads at each substation interact over a complex transmission network, but nearly everything that happens below the substation level is left uncoordinated. Electricity is an example of a commodity with inelastic demand – in the U.S., people are used to having it all the time, whenever they want. Bitar thinks that mindset will need to change slightly.

All the talk of the smart grid wouldn’t be nearly so complex if solar and wind, for example, were a reliable supply. But those resources are variable, and the gaps must be compensated by traditional bulk power generation, effectively defeating the purpose of a renewable source.

In an intelligent grid, this variability in supply would be balanced through the coordination of flexible distributed energy resources at the periphery of the system. Power would be produced locally and consumed locally, giving rise to self-sufficient communities or cities, called microgrids. Such an approach would decrease the need to transmit bulk power hundreds of miles to counterbalance fluctuations in renewable sources.

The architecture of such a system, which requires sensors and actuators in appliances, electric vehicles and the like, isn’t the hard part, Bitar said. The hard part is the design of algorithms to efficiently manage the deluge of information produced by those sensors in order to coordinate the simultaneous control of millions of distributed energy resources on fast time scales.

Much of this coordination will involve using flexibility in demand to compensate for variability in supply. For example, electric vehicles, considered a viable alternative to internal combustion engines, need to plug into the grid in order to charge. But because they’re battery-based, the demand for their charge is flexible – for example, utilities could offer monetary incentives to electric vehicle owners willing to shift their charging patterns. Coordinating that flexibility with a variable resource like rooftop solar could lead to increased penetration of this renewable energy resource while supplying clean power to electric vehicles

Finland’s largest solar power plant under construction in Oulu

Pilot results show that solar systems in Oulu produce as much electricity as those in northern Germany. Photo: Kalevi Rytkölä / Yle

Finland’s largest solar power plant, comprising of 1,600 solar panels producing 420 kilowatts of power, will be built in Oulu on the roof of the local printing plant this spring. The northern city of Oulu is quickly making a name for itself as a pioneer in the use of renewable energy sources.

According to yle.fi, Oulun Energia Group has announced plans to build a solar power unit on the roof of the local Kaleva newspaper’s printing plant in Oulu this spring. The 420-kilowatt unit will have 1,600 solar panels, combining to make a total panel surface area of approximately 2,400 square metres. Along with the support equipment, the setup will cover near to 3,200 square metres, which equals nearly half a football field.

System installation will begin in April, and the objective is for the unit to be operational by June 2015.

“On a clear summer day, we expect to gain up to 90 percent of the electricity required to run the Kaleva printing operations via solar. Annually, the solar energy obtained should cover about 10 percent of the printing house’s electricity costs,” says Kaleva’s CFO Esko Jokelainen.

The manufacture of solar panels in Finland is only in its early stages, so the panels for a project this large must be ordered from Germany. All of the other labour for the installation, from transport to assembly, will be carried out by local employees from the northern Finland region.

“Solar energy and other distributed energy production solutions will proliferate in the next few years and therefore create more jobs in northern Finland as well,” says Oulun Energia Group’s Sales Director Seppo Tuomi.

Oulun Energia Group generates, transmits, distributes and sells electricity and district heating in the Oulu region and is owned by the city of Oulu.

Why Oulu?

Located in North Ostrobothnia, Oulu is the largest city in northern Finland and the sixth largest city in the country, with a population over 200,000. It is one of the northernmost larger cities in the world. Situated this far north, one could wonder how a solar plant could be feasible with so many dark winter months in the year.

But the city of Oulu has taken on the role of a ‘living lab’, where residents experiment with new technologies from ICT to cleantech. Consequently, in per capita R&D spending, it ranks first in Finland and fifth in Europe. Oulu also has Europe’s largest technology park.

Oulun Energia Group conducted a pilot project for solar energy, testing the efficacy of 16 customer solar systems installed on local homes.

The pilot was surprisingly successful, producing results that were comparable to solar energy production conditions elsewhere. If properly situated, a 5-kilowatt system of 20 panels produced up to 4,500 kilowatts of electricity, which directly corresponds to a similar system in northern Germany.

In the Oulun Energia Group’s report on the pilot project, Tuomi is confident that there is significant potential for growth for photovoltaic systems in Finland.

“Solar energy systems are suitable for both businesses and consumers. Using them in the summer time to cool down property is particularly profitable. The cost of the panels is low, the payback period is reasonable and in ideal locations, the costs are clearly cheaper than grid electricity.”

The EU has set a climate target that 38 percent of member countries’ electricity consumption should be obtained from renewable energy sources by the year 2020.