Generating 'Green' Electricity: Waste Heat Converted to Electricity Using New Alloy

During a small-scale laboratory demonstration, University of Minnesota researchers showed how their new material can spontaneously produce electricity when the temperature is raised a small amount. Pictured (from left) are aerospace engineering and mechanics professor Richard James, PhD student Yintao Song and post-doctoral researchers Kanwal Bhatti and Vijay Srivastava. (Credit: Image courtesy of University of Minnesota)

Science Daily  — University of Minnesota engineering researchers in the College of Science and Engineering have recently discovered a new alloy material that converts heat directly into electricity. This revolutionary energy conversion method is in the early stages of development, but it could have a wide-sweeping impact on creating environmentally friendly electricity from waste heat sources.

"This research is very promising because it presents an entirely new method for energy conversion that's never been done before," said University of Minnesota aerospace engineering and mechanics professor Richard James, who led the research team."It's also the ultimate 'green' way to create electricity because it uses waste heat to create electricity with no carbon dioxide."Researchers say the material could be used to capture waste heat from a car's exhaust that would heat the material and produce electricity for charging the battery in a hybrid car. Other possible future uses include capturing rejected heat from industrial and power plants or temperature differences in the ocean to create electricity. The research team is looking into possible commercialisation of the technology.To create the material, the research team combined elements at the atomic level to create a new multiferroic alloy, Ni₄₅Co₅Mn₄₀Sn₁₀. Multiferroic materials combine unusual elastic, magnetic and electric properties. The alloy Ni₄₅Co₅Mn₄₀Sn₁₀ achieves multiferroism by undergoing a highly reversible phase transformation where one solid turns into another solid. During this phase transformation, the alloy undergoes changes in its magnetic properties that are exploited in the energy conversion device.During a small-scale demonstration in a University of Minnesota lab, the new material created by the researchers begins as a non-magnetic material, then suddenly becomes strongly magnetic when the temperature is raised a small amount. When this happens, the material absorbs heat and spontaneously produces electricity in a surrounding coil. Some of this heat energy is lost in a process called hysteresis. A critical discovery of the team is a systematic way to minimize hysteresis in phase transformations. The team's research was recently published in the first issue of the new scientific journalAdvanced Energy Materials.

Watch a short research video of the new material suddenly become magnetic when heated:http://z.umn.edu/conversionvideo.

In addition to Professor James, other members of the research team include University of Minnesota aerospace engineering and mechanics post-doctoral researchers Vijay Srivastava and Kanwal Bhatti, and Ph.D. student Yintao Song. The team is also working with University of Minnesota chemical engineering and materials science professor Christopher Leighton to create a thin film of the material that could be used, for example, to convert some of the waste heat from computers into electricity.

"This research crosses all boundaries of science and engineering," James said. "It includes engineering, physics, materials, chemistry, mathematics and more. It has required all of us within the university's College of Science and Engineering to work together to think in new ways."

Funding for early research on the alloy came from a Multidisciplinary University Research Initiative (MURI) grant from the U.S. Office of Naval Research (involving other universities including the California Institute of Technology, Rutgers University, University of Washington and University of Maryland), and research grants from the U.S. Air Force and the National Science Foundation. The research is also tentatively funded by a small seed grant from the University of Minnesota's Initiative for Renewable Energy and the Environment.

Solar Energy Creates Opportunities for Eco-Entrepreneurs

Solar Energy Creates Opportunities for Eco-Entrepreneurs

Using solar energy means one less home burning fossil fuels, and reduces the creation of greenhouse gas.

Things are looking sunny for the solar industry, but it’s not out of the woods quite yet. Even with tax incentives and rebates, cost is still a major factor for many. The $25,000 – $30,000 price tag for the average solar system remains a fair chunk of change for most, and a shortage of silicon limited production and increased prices for panels in 2006. But these limitations are temporary.

Producers are ramping up production, financing is improving, and costs will fall as production continues to increase. According to the Solar Energy Industries Association (SEIA) , the cost of electricity produced by solar panels will drop to about 8-9 cents per kilowatt-hour in the next ten years, low enough to compete with natural gas or coal.

To ride this green wave, eco-entrepreneurs are pursuing a plethora of opportunities.

One such opportunity for eco-entrepreneurs lies in breakthrough technologies that drive down the price of solar. Companies such as Solar Energy Initiatives, Inc. are concentrating the sun’s energy with mirrors onto a small area of panels, reducing the cost of the overall system. Others are developing utility-scale solar power systems that heat water or oil to generate electricity.

In addition to creating the technologies of tomorrow, there are plenty of other opportunities for solar today. As production of solar power continues to grow and becomes increasingly competitive with electricity from other sources, who is going to install all of these systems? Today, most solar systems in the U.S. are installed in the states with the biggest rebates and tax incentives. If more states join in, or nationwide incentives become more attractive, expect the solar wave to spread across the nation, creating opportunities for eco-entrepreneurs to install the panels as fast as the industry can produce them.

And who is going to be up on the roof doing the actual work? It won’t matter how many panels are produced if there are not enough trained workers to install them. Solar companies are already running into a shortage of trained, qualified people. The ideal worker has a strong background in construction and electrical skills, with certified training specific to solar systems. Gerald Zepeda at Sun Light and Power says, “We often hire people with construction, plumbing, electrical, or similar experience and train them ourselves,” helping them achieve certification by the North American Board of Certified Energy Practitioners (NABCEP).

Van Jones, Executive Director of the Ella Baker Center for Human Rights, may have one answer for deploying renewable energy in America’s cities and keeping the green wave growing. Millions of people in the cities left behind by economic and environmental progress provide a ready pool of renewable energy workers, given the right training. Training people for new “green collar jobs” installing solar panels will keep the solar power growing, and get these people on track to rewarding careers and lives. As Jones says, they are not just creating jobs, but building “green paths out of poverty.”

Another Eco-company, BioSolar, Inc. which developed a breakthrough technology to produce bio-based materials from renewable plant sources that reduces the cost of PV solar panels said – solar energy is a true green source of energy. Most of the solar industry is focused on photovoltaic efficiency to reduce cost.

Eco-entrepreneurs can create training programs that provide the solar industry with the skilled workers it needs. Solar installers are doing their best to train the workers they need, but cannot keep pace on their own. Universities, community colleges, vocational schools and others are building renewable energy programs, but also find it challenging to keep up with demand.

Eco-entrepreneurs should look for opportunities to align with solar companies that want to outsource their training to focus on what they do best, putting in solar systems. One of the bright points in the energy bill just signed into law is that it will provide as much as $125 million dollars to grants to train tens of thousands of workers in green collar jobs. It’s just a start but from the solar industry perspective, but according to Zepeda , “it’s a step in the right direction.”

Although solar is growing rapidly, solar panels are still found on only a few scattered homes. Those who see the glass half empty might be discouraged by this, but those who see the glass half full will see a huge opportunity for solar still waiting to be realized. Success will be when every home generates its own electricity.

The opportunity does not stop with solar. Wind power, energy efficiency technology, and biofuels are all growing at a similar explosive pace. By one estimate, renewable energy in general already employs 8.5 million people in the US and might employ as many as many as 40 million people by 2030, accounting for a big chunk of the US economy as a whole. The environmental challenges we face are great, but the opportunities for eco-entrepreneurs willing to take on these challenges are limitless.

-By Glenn Croston.

Glenn Croston is a biologist, father and author fighting climate change and working toward a greener world at home and at work. He is the author of 75 Green Businesses You Can Start to Make Money and Make a Difference, a book that lays out paths for innovative eco-entrepreneurs to join the booming green economy in renewable energy, green buildings, food, water, services, transportation, farms, and other areas, scheduled to come out with Entrepreneur Press in 2008. Glenn holds a PhD in biology from the University of California, San Diego.

Lowa State hybrid lab combines technologies to make biorenewable fuels and products

AMES, Iowa – Laura Jarboe pointed to a collection of test tubes in her Iowa State University laboratory.

Some of the tubes looked like they were holding very weak coffee. That meant microorganisms – in this case, Shewanella bacteria – were growing and biochemically converting sugars into hydrocarbons, said Jarboe, an Iowa State assistant professor of chemical and biological engineering.

Some of the sugars in those test tubes were produced by the fast pyrolysis of biomass. That’s a thermochemical process that quickly heats biomass (such as corn stalks and leaves) in the absence of oxygen to produce a liquid product known as bio-oil and a solid product called biochar. The bio-oil can be used to manufacture fuels and chemicals; the biochar can be used to enrich soil and remove greenhouse gases from the atmosphere.

Iowa State’s Hybrid Processing Laboratory on the first floor of the new, state-built Biorenewables Research Laboratory is all about encouraging that unique mix of biochemical and thermochemical technologies. The goal is for biologists and engineers to use the lab’s incubators, reactors, gas chromatography instruments and anaerobic chambers to find new and better ways to produce biorenewable fuels and chemicals.

“Biological processes occur well below the boiling point of water, while thermal processes are usually performed hundreds of degrees higher, which makes it hard to imagine how these processes can be combined,” said Robert C. Brown, an Anson Marston Distinguished Professor in Engineering, the Gary and Donna Hoover Chair in Mechanical Engineering, and the Iowa Farm Bureau Director of Iowa State’s Bioeconomy Institute.

“In fact, these differences in operating regimes represent one of the major advantages of hybrid processing,” Brown said. “High temperatures readily break down biomass to substrates that can be fermented to desirable products.”

Jarboe’s research is one example. She’s trying to develop bacteria that can grow and thrive in the chemicals and compounds that make up bio-oil. That way, they can ferment the sugars from bio-oil with greater efficiency and produce more biorenewable fuels or chemicals.

Another example of mixing the biochemical with the thermochemical is the work of Zhiyou Wen, an associate professor of food science and human nutrition, and Yanwen Shen, a doctoral student in his research group.

They’re working to break down a bottleneck in the fermentation of synthesis gas – a mixture of carbon monoxide and hydrogen that’s produced by the partial combustion of biomass in a gasifier. The fermentation process slows when researchers dissolve the gas into a liquid that can be used by microorganisms to produce biofuels. They’re looking for bioreactor technologies that boost the mass transfer of the synthesis gas without adding energy costs.

A third example is the work of DongWon Choi, a former doctoral student and post-doctoral research associate at Iowa State who’s now an assistant professor of biological and environmental sciences at Texas A&M University Commerce. He continues to collaborate in the hybrid lab by working with microalgae that convert carbon dioxide into oil that can be used to produce biofuels.

That oil is currently harvested with solvents or mechanical presses. Both processes produce a lot of waste and the resulting waste management problems. Choi is using pyrolysis technology to heat the algae and convert it into jet and diesel fuels without the waste.

And the researchers say the hybrid lab’s mix of people, technologies, equipment and ideas is beginning to show results.

“The hybrid lab provides enormous opportunities for performing biological-based processes for producing biofuel from thermochemically treated biomass,” Wen said.

Yes, said Jarboe, “I think it is working well. This is a long process, but we’re writing research proposals and papers. Everybody loves the idea of this hybrid approach. It has such a promising future; the challenge is in the collaboration.”

The hybrid lab is starting to make the collaboration easier, though.

Brown said he’s noticed the students who work in the hybrid lab seem to be comfortable crossing thermochemical and biochemical lines: “Just like children from different cultures often learn to communicate with one another more quickly than do their parents, graduate students seem to pick up cross disciplinary culture and language faster than their faculty advisers.”

GE Combines Natural Gas, Wind, and Solar

ENERGY

GE Combines Natural Gas, Wind, and Solar

The hybrid plant could be the cheapest and easiest way to add renewable energy to the grid.

GE has unveiled a groundbreaking power plant, the first to seamlessly integrate wind and solar power with natural gas. This 530-megawatt plant, set to commence operations in Turkey in 2015, is made possible by a flexible, high-efficiency natural gas system introduced by the company just two weeks ago. The solar thermal power system, a creation of eSolar, a GE-backed startup based in Burbank, California, further enhances the plant's practicality.

GE envisions a future where hybrid plants like this could become the norm in certain parts of the world. This innovative technology is particularly beneficial for countries operating on 50-hertz electricity, such as China and the European Union, as it could significantly aid them in achieving their renewable energy goals.

Adding solar power to natural gas plants is a familiar idea, but it hasn't been economical without government subsidies. GE says that because of its new turbines and related equipment, these hybrid plants can be competitive even without government support for utilities with the right combination of sunlight and natural gas prices. 

While combining solar thermal power and natural-gas turbines is not new, adding wind power to such a system is, GE says. Pairing wind with the natural gas plant helps reduce the cost of wind power—the wind farm can share some of the natural gas plant's control systems and its connection to the grid. The natural gas plant also smooths out variations from the wind turbines.

Solar thermal power involves concentrating sunlight and using the resulting heat to produce steam. That steam can be fed into the steam turbine at a natural gas combined cycle plant to boost its power output.

The solar concentrator array from eSolar helps lower costs in two ways. Its modular concentrator system is easy to install and modify for specific plant needs. It also produces higher-temperature steam than some previous solar thermal systems, increasing power output. GE has also developed a natural gas power plant that is highly efficient and whose power output can easily be adjusted to make up for variations in power output from solar power.

One of the most compelling aspects of this hybrid power plant technology is its cost-effectiveness. Connecting a solar thermal system to a natural gas power plant eliminates the need for a separate steam turbine and related equipment, resulting in a potential 50 per cent reduction in the cost of a solar thermal system. Jon Van Scoter, CEO and president of eSolar, confirms this. In contrast, Paul Browning, vice president of thermal products at GE, hails it as 'the most cost-effective form of solar energy available today.'

Biofuels: Threat or opportunity for women?

SUBMITTED BY DANIEL KAMMEN

In Africa, where two-thirds of farmers are women, the potential of biofuels as a low or lower-carbon alternative fuel, with applications at the household energy, community and village level, to a national resource or export commodity, has a critical gender dimension. The key question is: how will increased biofuel production affect women?

One logical approach to look at the impacts on women is to use a computable general equilibrium model that tracks the economic implications of new crops and how patterns of trade and substitution will change. It’s essential to account for the complexities involved and rely not on a simple, traditional commodity model but one that tracks the impacts on women through changing prices and demands for crops to be sold on local and international markets. Who gains and who loses as prices change and as the value of specific crops and land changes?

In a detailed modelling effort based on the situation today in Mozambique, World Bank economist Rui Benfica and colleagues (Arndt, et al., 2011) found that even with significant land area available, the impacts of large increases in bio-fuels production — which are now underway — will do little to benefit women. This is large because shifts to export-oriented and commercial agriculture, while they may raise export earnings, often exclude women. Women are often far overburdened by work and time commitments to subsistence farming, other income-generating activities, and household work, including child care. The CGE model shows that financially profitable bio-fuel expansions may widen this gap and reinforce this exclusion.

Interestingly, a focus on primary school education for girls (a good idea already, but one made quantitative in these studies) in skills training programs can address this concern. However, For many women, the same problem remains: there is simply no time to take advantage of new opportunities. Mozambique is a crucial illustrative example, as its agriculture sector heavily depends on small-scale farmers, primarily women. 

Thus, bio-fuel policies — both positive and negative — can lead to attention to issues of gender inequality, where planning can play a significant role. Our challenge is to reflect these shared benefits – food security, economic opportunity, and climate protection, in clear and transparent metrics. By doing so, we can gain insights into the economic realities of poor households.

Do solutions exist that take advantage of new commodities and markets without essentially pricing poor women farmers out of local subsistence agriculture (or onto even more scarce land) and denying them the benefits of added commercial sales? One avenue is working to anticipate these changes – based on the sort of modelling that Rui Benfica and colleagues did – and to issue land certificates to women so they can more easily hold onto their land if commercial markets begin encroaching on their agricultural holdings. 

One potential solution is that applied in Ethiopia, where a community-driven and managed land certification system has provided women with land-tenure security. This is explored, along with other solutions in a recent book edited by Calestous Juma of Harvard University,The New Harvest: Agricultural Innovation in Africa (2011).  

What else can be done? Agricultural productivity requires an enabling infrastructure beyond the requisite land, seeds, and water. Networks to bring crops to market with minimal losses on the fields and post-harvest (where up to one-third of yields can be lost in some poor nations) are one aspect to consider, as is the use of information technology to warn even the most impoverished subsistence farmers (often women) of extreme weather and to help communities find new outlets for their commodities. Another angle is added planning for diversified cropping, including cases where food, feed, and fibre (for durable goods or biofuels) can be grown together in more resilient eco-agricultural systems.

Conventional fossil fuels sometimes 'greener' than biofuels: study

To combat soaring fuel prices and cut greenhouse gas emissions, the aviation industry is racing toward the use of biofuels. In 2008, Virgin Atlantic became the first commercial airline to fly a plane on a blend of biofuel and petroleum. Since then, Air New Zealand, Qatar Airways and Continental Airlines, among others, have passed biofuel test flights, and Lufthansa is racing to be the first carrier to run daily flights on a biofuel blend.

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However, researchers at MIT say the industry may want to make sure it has examined biofuels' complete carbon footprint before making an all-out push. They say that when a biofuel's origins are factored in — for example, taking into account whether the fuel is made from palm oil grown in a clear-cut rainforest — conventional fossil fuels may sometimes be the "greener" choice.

"What we found was that technologies that look very promising could also result in high emissions if done improperly," says James Hileman, principal research engineer in the Department of Aeronautics and Astronautics, who has published the results of a study conducted with MIT graduate students Russell Stratton and Hsin Min Wong in the online version of the journal Environmental Science and Technology. "You can't simply say a biofuel is good or bad — it depends on how it's produced and processed, and that's part of the debate that hasn't been brought forward."

Hileman and his team performed a life-cycle analysis of 14 fuel sources, including conventional petroleum-based jet fuel and "drop-in" biofuels: alternatives that can directly replace traditional fuels with little or no change to existing infrastructure or vehicles. In a previous report for the Federal Aviation Administration's Partnership for Air Transportation Noise and Emissions Reduction, they calculated the emissions throughout the life cycle of a biofuel, "from well to wake" — from acquiring the biomass to transporting it to converting it to fuel, as well as its combustion.

"All those processes require energy," Hileman says, "and that ends up in the release of carbon dioxide."

In the current Environmental Science and Technology paper, Hileman considered the entire biofuel life cycle of diesel engine fuel compared with jet fuel, and found that changing key parameters can dramatically change the total greenhouse gas emissions from a given biofuel. 

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In particular, the team found that emissions varied widely depending on the type of land used to grow biofuel components such as soy, palm and rapeseed. For example, Hileman and his team calculated that biofuels derived from palm oil emitted 55 times more carbon dioxide if the palm oil came from a plantation located in a converted rainforest rather than a previously cleared area. Depending on the type of land used, biofuels could ultimately emit 10 times more carbon dioxide than conventional fuel.

"Severe cases of land-use change could make coal-to-liquid fuels look green," says Hileman, noting that by conventional standards, "coal-to-liquid is not a green option."

Hileman says the airline industry needs to account for such scenarios when thinking about how to scale up biofuel production. The problem, he says, is not so much the technology to convert biofuels: Companies like Choren and Rentech have successfully built small-scale biofuel production facilities and are looking to expand in the near future. Rather, Hileman says the challenge is in allocating large swaths of land to cultivate enough biomass, in a sustainable fashion, to feed the growing demand for biofuels.

He says one solution to the land-use problem may be to explore crops like algae and salicornia that don't require deforestation or fertile soil to grow. Scientists are exploring these as a fuel source, particularly since they also do not require fresh water.

Total emissions from biofuel production may also be mitigated by a biofuel's byproducts. For example, the process of converting jatropha to biofuel also yields solid biomass: For every kilogram of jatropha oil produced, 0.8 kilograms of meal, 1.1 kilograms of shells and 1.7 kilograms of husks are created. These co-products could be used to produce electricity, for animal feed or as fertilizer. Hileman says that this is a great example of how co-products can have a large impact on the carbon dioxide emissions of a fuel.

Hileman says his analysis is one lens through which policymakers can view biofuel production. In making decisions on how to build infrastructure and resources to support a larger biofuel economy, he says researchers also need to look at the biofuel life cycle in terms of cost and yield.

"We need to have fuels that can be made at an economical price, and at large quantity," Hileman says. "Greenhouse gases [are] just part of the equation, and there's a lot of interesting work going on in this field."

Provided by Massachusetts Institute of Technology (news : web)