How one schoolboy could cut 1.8m tons of CO2Jonny Cohen has been dreaming of making America’s school buses greener since he was 12. Now the high school inventor is on the verge of success.
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They were aerodynamically hopeless. Their unyielding lines, sharp edges and chunky bodies increased air resistance and drag. Even aged 12, Cohen knew about these things. He had been studying aerodynamics in extra-curricular classes.
“I was so excited by it and started sketching things and thinking: Wow! Things could be so much more efficient just by changing their shape,” he told Open Knowledge. “Then I noticed the school buses.”
His idea was straightforward: to make school buses more aerodynamic so they would use less fuel and be less polluting. “We hear about school buses running a four-day week because of budget cuts,” Cohen says. “If we reduce their gasoline bill it could make a difference.”
Now he is seeking approval for his invention that could ultimately slash CO2 emissions by 1.8 million tons—equivalent to taking 320,000 American cars off the road for a year.
The GreenShield is a fiberglass 'airfoil' that fits onto the leading edge of the bus roof. It has a curved raised front and then tapers down for about a meter to the sharp trailing edge. It acts to smooth the flow of air up and over the surface of the roof.
Big fuel savingsThe prototype, tested in wind tunnels and on a school bus donated by the owner of the Cook-Illinois Bus Company, has performed impressively. The results suggest that buses fitted with the GreenShield would use between 10% and 20% less gasoline, saving from $600 to $1200 dollars a year, and reducing carbon emissions accordingly.
There are about 480,000 school buses operating in America. They produce about nine million tons of CO2 a year, almost equivalent to the annual emissions of two coal-fired power stations, calculates the Environment Protection Agency.
If all the school buses in America achieved maximum fuel savings thanks to GreenShields, Jonny Cohen’s device would have saved a staggering $576 million dollars and 1.8 million tons of CO2—equivalent to the CO2 produced from the annual electricity usage of over 203,000 American homes.
These are heady numbers, and they have persuaded the Cook-Illinois Bus Company to put in a provisional order to fit GreenShields to its fleet of over 4000 school buses if the device is approved for mass production.
The last hurdleA manufacturer is lined up, and a provisional patent is in the pipeline. Weighing in at just eight pounds (3.6 kilograms), the GreenShield can be fitted very easily and quickly, says Cohen.
And although it now costs about $500 dollars to manufacture, if production can be scaled up to make use of injection moulding techniques the cost could be brought down to around $100 dollars. It could also be made from recycled plastics rather than energy-intensive fiberglass.
All that remains is for the federal authorities and the Department of Transport in Illinois to approve the GreenShield.
“The biggest challenge is getting GreenShield approved. People don’t want to say yes as nothing good can come of it for them so there is no incentive to say yes," says Cohen. "On the other hand, if they do say yes and someone gets hurt then they fear they are liable.”
Many semi-trailer trucks use airfoils to bridge the gap between the truck cab and the cargo container in order to reduce drag. But until Jonny Cohen noticed something on the way to school, nobody thought to do the same for school buses.
So could the GreenShield be attached to other vehicles? Certainly, says Cohen, although they would need to be reasonably large and have relatively long working lives to make the investment worthwhile.
In the meantime, however, this young inventor is concentrating on helping turn an enduring American icon from a gas-guzzling workhorse into a leaner, greener thoroughbred.
You can find out more about the GreenShields project here.