Besides being favored by geektastic chefs who want to make instant ice cream, liquid nitrogen has some other sweet potential. A team of researchers from the University of Leeds and the Chinese Academy of Sciences came up with system using this inert, colorless, odorless gas that could cut slice power plants' fuel consumption in half.
Power plants dealing with peak loads are like elementary school teachers returning from a short vacation to face a classroom full of students who have all just eaten a ton of sugar. In other words, it's a big strain. Specifically, it forces power plants to resort to expensive, inefficient generators. More gas-firing, more coal burning, more pollution.
To address this energy conundrum, a team led by University of Leeds engineering professor Yulong Ding, figured out a novel approach that could cheaply store excess energy and then use that during the peaks. I've heard of many developments in improving energy storage for power plants, especially with renewables coming online. However, Ding and his fellow engineers are the only ones I've seen so far with a promising plan that involves liquid nitrogen and oxygen. Liquid nitrogen on its own is amazing -- it freezes at −346 degrees Fahrenheit and boils at −321 degrees.
Here's how their system would work: Excess electricity generated during non-peak hours could be used to run a special unit that produces liquid nitrogen and oxygen, also known as "cryogen." (If you just thought about Ted Williams, you weren't the only one.) As soon as demand goes up, the nitrogen would get boiled using waste heat from the power plant. According to the university, "The hot nitrogen gas would then be used to drive a turbine or engine, generating 'top up' electricity."
As for the oxygen, that would get mixed with natural gas to improve the combustion process, making it more efficient and less polluting. The carbon dioxide produced would come out conveniently as dry ice, which is actually quite useful.
The researchers are saying such a system could cut power plants' fuel consumption by as much as 50 percent, in addition to reducing greenhouse gas emissions from the power production process. They recently published their findings (abstract) in the International Journal of Energy Research.
Right now their system just lives on paper, but it sounds like the team is itching to make an actual test version. I'm all for a cheaper, greener, and realistic way to address peak loads. After all, Ted Williams isn't the only one who needs extra cooling when the temperature soars.
Photo: Liquid nitrogen being used in a laboratory. Credit: Stian Martinsen.
Tags: Electricity, Energy Efficiency, Engineering, Green Tech
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