Energy & Environment
New system recovers fresh water from power plants
A new system devised by MIT engineers could provide a low-cost source of drinking water for parched cities around the world while also cutting power plant operating costs.
About 39 percent of all the fresh water withdrawn from rivers, lakes, and reservoirs in the U.S. is earmarked for the cooling needs of electric power plants that use fossil fuels or nuclear power, and much of that water ends up floating away in clouds of vapor. But the new MIT system could potentially save a substantial fraction of that lost water — and could even become a significant source of clean, safe drinking water for coastal cities where seawater is used to cool local power plants. The principle behind the new concept is deceptively simple: When air that’s rich in fog is zapped with a beam of electrically charged particles, known as ions, water droplets become electrically charged and thus can be drawn toward a mesh of wires, similar to a window screen, placed in their path. The droplets then collect on that mesh, drain down into a collecting pan, and can be reused in the power plant or sent to a city’s water supply system. The system, which is the basis for a startup company called Infinite Cooling that last month won MIT’s $100K Entrepreneurship Competition, is described in a paper published today in the journal Science Advances. Read more here.
MIT engineers build smart power outlet
Have you ever plugged in a vacuum cleaner, only to have it turn off without warning before the job is done? Or perhaps your desk lamp works fine, until you turn on the air conditioner that’s plugged into the same power strip. The problem with today’s arc-fault detectors, according to a team of MIT engineers, is that they often err on the side of being overly sensitive, shutting off an outlet’s power in response to electrical signals that are actually harmless.
The MIT team has developed a solution that they are calling a “smart power outlet,” in the form of a device that can analyze electrical current usage from a single or multiple outlets, and can distinguish between benign arcs — harmless electrical spikes such as those caused by common household appliances — and dangerous arcs, such as sparking that results from faulty wiring and could lead to a fire. The device can also be trained to identify what might be plugged into a particular outlet, such as a fan versus a desktop computer. Read more here.
Science & Tech
A quantum choreographer pursues MRI without magnets
After doctoral research at MIT generating insights on spin and novel methods for maneuvering quantum mechanical objects, Ashok Ajoy (PhD ’16), is now pioneering technologies with the potential to transform the fields of imaging and chemical analysis. Using diamond dust, laser light, and water, Ajoy and his colleagues at the University of California at Berkeley are pursuing alternatives to the multi-million dollar, room-size machines in current use. “Our vision is to achieve conventional magnetic resonance imaging at a fraction of the cost and to revolutionize industries that rely on nuclear magnetic resonance to study molecules, such as pharmaceutical companies,” he says. Read more here.
MIT engineers recruit microbes to help fight cholera
Cholera outbreaks are usually caused by contaminated drinking water, and infections can turn fatal if not treated. The most common treatment is rehydration, which must be done intravenously if the patient is extremely dehydrated. However, intravenous treatment is not always available to patients who need it, and the disease kills an estimated 95,000 people per year. MIT engineers have developed a probiotic mix of natural and engineered bacteria to diagnose and treat cholera, an intestinal infection that causes severe dehydration. The team’s new probiotic mix could be consumed regularly as a preventative measure in regions where cholera is common, or used to treat people soon after infection occurs. Read more here.