Imagine taking the heat waste from high-generating power plants and converting that material back into electricity. In the realm of thermoelectrics, this process has become a reality in the world of research and startups. With the increasing need to be more efficient and cost-effective with energy in the public and private sectors, full implementation of this technology could significantly reduce wasteful emissions from power plants and recycle more of the energy that is released in industries. Although the process of converting heat energy to electricity is nothing novel, the process has never been widespread because of the complicated adjustments to temperature that need to be made depending on level of output and the low level of electricity that is actually retained from waste compared to the cost needed to produce it.
Additionally, this kind of technology is slow to reach the markets and produces profit at a much slower pace as it gets integrated into the community of energy technology. These factors have rendered the process unappealing to investors and thus hindered significant funding until recently, when collective urgency emerged from international conferences like the United Nations Conference on Climate Change (COP21) that have made public and private sectors alike impose regulations that more strictly limit energy waste and stress renewability and sustainability. Now, startups like Alphabet Energy and RedWave Energy, as well as research labs from Yale and University of Florida, have piqued public interest with cheaper and more effective methods by which to capture more heat waste from power plants for electricity. With increased interest in viable options to cut back on energy waste quickly, thermoelectric technology is emerging with great promise.
In the world of startups, several noteworthy companies are making substantial progress in the effectiveness of thermoelectrics, making great strides in being more readily available to industries as they are backed by seven figure investments. A thermoelectric is a material that turns heat into electricity. The concept itself is straightforward and is already used in capacities besides renewable energy. NASA, for example, uses thermoelectrics to power spacecraft, but the practice is much too expensive to be translated to smaller businesses with power plants. Matt Scullin, the founder of startup Alphabet Energy, was inspired to found the company from Michigan State University’s development that improves upon existing thermoelectric technology, using the compound tetrahedrite to make the process more efficient and cheap (1). With a combination of materials science and mechanical engineering, Alphabet Energy uses thermoelectric PowerCards that acquire power through various heat sources, like the exhaust stack of a coal-burning power plant. The volume of waste emitted from a particular power source determines the number of PowerCards required to maximize heat waste capture. From there, Alphabet moved into the next phase of development to produce a more advanced Power Generating Combustor (PGC) system, which generates electricity from natural gas flaring (2). The PGC system, backed with a $23.5 million investment from Schlumberger Limited, is projected to eventually eliminate the need for diesel and natural gas-powered generators, as well as electrical grid connections. The company hopes to be able to embed its technology in vehicle engines and diesel generators. In this way, Alphabet Energy is making progress not only in reducing waste from currently operating power plants, but also through developing completely new methods of acquiring renewable energy. Alphabet Energy’s technology expansion has led it to open an office in Houston, where it will seek to maintain pace with the industry demand for remote power generation solutions (2).
RedWave Energy is another up and coming startup that differs from Alphabet in that it targets low-temperature heat waste, which expands the types of power plants that can benefit from thermoelectric technology. The Chicago-based company uses flexible sheets of metal covered with tiny antennas that transform heat into electricity for temperatures between 70 and 250 degrees Celsius (3). To date, RedWave states that no other company has managed to acquire heat waste at a competitive level for that temperature range. The microantennas in RedWave’s technology captures electromagnetic radiation of heat the same way television and radio antennas capture electromagnetic waves. RedWave recently received millions of dollars from celebrity couple Will and Jada Smith’s foundation, as well as a $3 million grant from the Department of Energy’s early-stage high-risk energy program called ARPA-E (4). Earlier this month, RedWave’s Series B round of its technology closed and beta testing is expected to begin within a year before hitting the market. An additional benefit to RedWave’s technology besides the lower temperature allowance is the collaboration of research occurring nationwide, demonstrating how interdisciplinary approaches in energy technology are leading to quicker and potentially very lucrative solutions. The Idaho National Lab helped develop the nanoantenna technology, while professors at the University of Colorado-Boulder designed the technology that funnels the electrons off the antenna (4). Furthermore, a Cambridge, Massachusetts manufacturer is helping make the nanoantenna-filled film. This integration of intellectual capital is paving the way for staggering advances over a relatively short period of time.
Beyond startups, the academic community is providing the theoretical models needed to maximize accuracy and reduce technical error for when products hit the market. Two physicists from the University of Florida, for example, are further developing nanowire technology to recover heat waste on the engines of ships and manufacturing refineries in addition to power plants (5). They are also studying the complexity of thermoelectric device requirements for different conditions depending on the temperature gradient between two leads, for different electrical loads, or the amount of power being consumed at a given moment. Their research is spearheading efficient devices that soon can become more widespread. Engineers and researchers at Yale University’s Department of Chemical and Environmental Engineering have developed a new technology using low-temperature waste heat to generate power, a concept popularized in the private sector by RedEnergy that Yale hopes to improve. Combined heat and power (CHP) technology uses high-temperature waste heat, and is already used in the United States, contributing to around 12% of the country’s total electricity according to Inside Energy (6). Unlike CHP technology, though, low heat fully operates even with heat source fluctuations. The Yale researchers published their “nanobubble membrane” development in the Nature Energy journal on June 27, describing how the mechanism traps tiny air bubbles underwater and creates water flow through temperature adjustment (6). These technological improvements from esteemed scientists demonstrate how the field possesses great academic rigor in addition to being fiscally promising in the private sector.
With warnings about climate change reaching governments in effective ways, thermoelectric technology could provide a promising solution to the energy crisis in the near future. The European Union’s Renewable Energy Directive entailed that members of the European Union should be producing 20% of its energy from renewable sources by 2020 (7). This, combined with other initiatives like the United Nations Conference on Climate Change, demonstrate the need for industries to significantly alter the way they treat energy if goals are to be met at proposed deadlines. Dr. Zulfigar of Bournemouth University in the United Kingdom is working on heat transfer and fluid dynamics as part of his overarching goal of creating better forms of energy reserves. His approaches involve materials sciences, heat and fluids within heat transfer and thermodynamics, and storage and corrosion engineering (7). Improvements in the field of thermoelectrics show immense promise in reducing the amount of waste produced in society, one that requires massive amounts of energy that is at present unsustainable for much longer. Waste heat levels that can be recovered in the United States alone are estimated to be high enough to power tens of millions of households (8). The integration of heat recovery from power plant waste into standard building practices and power generators has the potential to provide a widespread, effective solution to curbing excessive energy production. “Our energy reserves used at our current rates will last us perhaps another 50 to 60 years for oil and gas, and coal another 100 years,” Dr. Khan stated when discussing his research. “What are we going to do when that runs out?” Fortunately, thermoelectric technology is providing a viable answer in the making.
(1) Palca, Joe. "A Lot Of Heat Is Wasted, So Why Not Convert It Into Power?" NPR. NPR, 20 Aug. 2015. Web. 27 July 2016.
(2) NGI Staff Reporters. "Natural Gas Intelligence Is a Leading Daily Provider of Natural Gas Prices, Natural Gas News, and Gas Pricing Data to the Deregulated North American Natural Gas Industry." NGI's Shale Daily. Natural Gas Intelligence, 13 July 2013. Web. 27 July 2016.
(3) Fehrenbacher, Katie. "This Startup Is Using Tiny Antennas To Capture Waste Heat." Fortune. Fortune, 19 July 2016. Web. 27 July 2016.
(4) Marotti, Ally. “RedWave Raises $5.5 Million to Turn Heat into Electricity.” Chicagotribune.com. Chicago Tribune, 21 July 2016. Web. 27 July 2016.
(5) Zyga, Lisa. "New Device May Make Converting Waste Heat to Electricity Industrially Competitive." Phys.org. Science X Network, 21 May 2016. Web. 27 July 2016.
(6) Butao, Sarene Mae. "Energy From Low-Temperature Heat Waste Can Now Be Used In Producing Power, Yale Researchers Developed A Way." University Herald RSS. University Herald, 04 July 2016. Web. 27 July 2016.
(7) Bournemouth University. "Developing Reliable Renewable Energy Sources." ScienceDaily. ScienceDaily, 25 July 2016. Web. 27 July 2016.
(8) Butao, Sarene Mae. "Energy From Low-Temperature Heat Waste Can Now Be Used In Producing Power, Yale Researchers Developed A Way." University Herald RSS. University Herald, 04 July 2016. Web. 27 July 2016.
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