Hybrid electric plane could save lives
Siobhan Treacy | January 20, 2021Researchers from MIT created a concept for propulsion that could eliminate up to 95% of aviation’s nitrogen oxides (NOx) emissions and reduce the number of early deaths from airplane pollution by 92%.
The team was inspired by emissions control systems of inground vehicles. Heavy-duty diesel trucks have post-combustion emissions controls systems to reduce NOx generation from engines. The team’s proposal is a similar design for planes, but with an electronic twist.
Source: Unsplash
Planes are currently propelled by jet engines anchored beneath each wing. The engine houses a gas turbine that powers the propeller to move the plane through the air and the exhaust from the turbine flows out of the back. Because of the configuration, it hasn’t been possible to use post-combustion emission controls as they would interfere with thrust from the engines.
The team has proposed a turbo-electric design. The power source is still a conventional turbine integrated within the plane’s cargo hold. The gas turbine drives a generator to produce electricity to power the plane’s wing-mounted propellers. Emissions from the gas turbine would be fed to the emissions control system that would clean the exhaust before ejecting it into the atmosphere.
The design separates thrust producing propellers from the power generating gas turbine. The propellers and fans would feed into an emissions control system, and the bulk of this hybrid-electric system would fit within the belly of a plane. With the extra weight, a plane would need 0.6% more fuel to fly. The extra weight is only a few hundred kilograms, rather than the extra tons that batteries would add. This is a more feasible goal than all other electric planes that have been proposed.
The team found that the hybrid-electric design would eliminate 95% of NOx emissions. If the system was rolled out across all aircraft around the world, the team estimates it would eliminate 92% of pollution-related deaths due to aviation. To gather this information, the team used a global model to map the flow of aviation emissions through the atmosphere and calculated how much different populations around the world would be exposed to emissions. They then converted the exposures to mortalities.
A paper on the proposed plan was published in Energy in Environmental Science.
Early deaths from jet exhaust pollution? People need to stop building homes at 38,000 feet.
In reply to #1
Corona virus has done a better job, fewer planes flying, less NOx, fewer collisions between planes and building above 35000 feet. Support your local Corona Virus and reduce early deaths from overexposure to laughing it's a gas.!
No mention of the thrust produced by the jet's exhaust stream being lost to the pollution control devices. To me it's a glaring omission that indicates it was not considered.
How about speed with props vs. jets? If it takes 12 hrs. to cross the Atlantic vs. 6 hrs. that means the turbine will have to run twice as long (for example). How will that relate to emissions? It is an interesting idea nevertheless.
This is the most ridiculous thread I've seen here.
In reply to #5
You're not looking very hard . . . .