Now, in a project funded by the U.S. Army, two University of Florida engineers have designed, built and successfully tested a combined power-refrigeration system that can provide all three – and, with further development, be made compact enough to fit inside a military jet or large truck.
“If you’re in a forward base in Iraq, it costs you the same per gallon of water as it does per gallon of fuel,” said William Lear, a UF associate professor of mechanical and aerospace engineering. “It would be better to just have to send fuel out there, especially if you could get refrigeration and water out of it – which is what our system achieves.”
Lear and UF mechanical engineering professor S.A. Sherif have published several academic papers on various aspects of the system, which is being patented by UF. In November, they will present a paper discussing the system’s experimental results at the International Mechanical Engineering Congress & Exposition in Chicago.
Both the Federal Emergency Management Agency and the military now rely on large generators to produce electricity in hazard zones. For cooling, they either haul in ice or electricity-hogging refrigerators. Depending on the location and emergency, imported fresh water may be another major logistical challenge and expense.
Hoping to cut costs and simplify the process, the Army has provided a $750,000 grant to a small Gainesville company funding Lear and Sherif’s research on an alternative.
The engineering researchers’ solution: a small system that ties a novel gas turbine power plant to a heat-operated refrigeration system. The refrigeration makes the gas turbine more efficient, while also producing cool air and potable water. The turbine can run on conventional fossil fuels as well as biomass-produced fuels or hydrogen.
Lear said gas turbines are a common power generator used in everything from jet engines to electricity plants. The problem with traditional versions is that they lose efficiency both when not operated at full power and in warm temperatures, he said.
Seeking to erase this loss, he rerouted the path of gases passing through the turbine, cooling them via heat exchangers. Sherif, an expert in refrigeration, then tied the system to absorption units, cooling the gases still more.
Users can either tap all the cooling power to obtain peak efficiency for the turbine, or divert some for refrigeration or air conditioning. “You can decide how much of one you want versus how much of the other, depending on your needs,” Sherif said.
Lear said his experiments and computer models suggest that with all the cooling devoted to the turbine, it will be 5 percent to 8 percent more efficient than traditional turbines. With some cooling siphoned for other purposes, it was still 3 percent to 5 percent more efficient than the turbines. Contrasting traditional gas turbines, the system maintains its efficiency whether operated at peak or partial power.
A few percentage points might not seem like much, but it makes a big difference when fuel is scarce or expensive, particularly if refrigeration and water are added bonuses, Lear said. “Power companies would kill for a 1 percent gain,” he said.
The system, which makes water by condensing the turbine’s combustion gases, is capable of producing about one gallon of water for every gallon of fuel burned, Sherif said. The water would need to be treated to be potable, but even if untreated it could be used for cleaning or other purposes. Because the plant reuses gases so extensively, the power plant also has very low polluting emissions, Lear added.
Sherif, Lear and colleagues have built a working prototype of the plant for experiment and testing purposes. Housed in an engineering college laboratory, it appears at first as a maze of tubes and pipes reminiscent of a Dr. Seuss drawing. But a closer inspection reveals a carefully designed “flow pattern” routing gases through and around a small gas turbine, with dozens of electronic and pneumatic monitoring probes. Operators run the test plant from an adjacent control room.
Lear said further research is required to make the plant more compact and otherwise enhance its performance. That’s one of the goals of the Army’s Small Business Innovation Research Grant to the Gainesville company, Triad Research. He added that larger versions could be used in fixed locations as part of the normal power grid. For example, utilities could build the plant nearby a grocery store warehouse that required both electricity and cooling.
William Lear | EurekAlert!
Stretchable biofuel cells extract energy from sweat to power wearable devices
22.08.2017 | University of California - San Diego
Laser sensor LAH-G1 - optical distance sensors with measurement value display
15.08.2017 | WayCon Positionsmesstechnik GmbH
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
23.08.2017 | Life Sciences
23.08.2017 | Life Sciences
23.08.2017 | Physics and Astronomy