SCHOOL'S OUT: Jonny Cohen designed a plastic device that can cut diesel use by school buses.
Image: GreenShields
Fuel economy is hardly the most popular subject among teenagers, but it's a passion for 17-year-old Jonny Cohen, who's found a way to save schools money and reduce greenhouse gas emissions by increasing school bus fuel efficiency.
The idea popped into his head on a walk home from school when he was 12. The then-seventh-grader was taking summer classes on aerodynamics at Northwestern University, and it dawned on him there must be a way to streamline the bulky, boxy shape of school buses.
"I like to see things that are efficient. Things that are inefficient use more energy and are polluting," said Jonny, who lives in Highland Park, Ill. "I also understood that reducing carbon emissions from a school bus could reduce global warming."
With the help of friends and his sister Azza Cohen, a more formal effort took shape in 2008. They called it the Greenshields Project.
Azza, 19, said Jonny has always been an inventor. He blew things up, made his own intercom system and crafted a device to put cheese on a hamburger. But when Jonny ran into her room saying he could revolutionize school buses, Azza didn't think much of it at first.
"He'd had a lot of crazy ideas before, and I'd never really believed them," she said. "You're less inclined to believe a 12-year-old when they say they have a solution to a really pressing problem."
School bus emissions are a pressing issue. According to U.S. EPA, diesel exhaust from school buses contains pollutants that contribute to ozone formation, acid rain and global climate change. In addition, the fine particulate matter from diesel engines can cause lung damage, especially in children, and contributes to haze.
EPA created a national idling reduction campaign to cut down on air pollution from buses. But, to date, no product or program exists that would reduce emissions quite like the GreenShield.
Putting a fuel hog on a diet
Jonny's original idea was to attach a streamlined, transparent Plexiglas cover over a school bus windshield to reduce drag and allow the vehicle to use less fuel.
The fourth-generation GreenShield, produced with help from Northwestern University's Segal Design Institute, looks radically different. Instead of a shield, it's more like a ski-jump-shaped hat installed on the roof of a bus, which reduces material and installation costs. Research shows the efficiency benefits are about the same.
Virtual, on-road and wind tunnel tests on school buses donated by the bus company Cook-Illinois Corp. found the GreenShield improves fuel economy 10 to 20 percent.
John Benish Jr., president of family-owned Cook-Illinois, said joining with GreenShields was a "perfect fit" for the company, which already runs most of its school buses on biodiesel.
"We're always looking for that next thing to make school buses a little greener, a little better and more efficient," he said.
Buses are the safest way to get children to school, but they're also fuel hogs that get only 4 to 6 miles per gallon. Studies show that one bus takes an average of 36 cars off the road, but GreenShields calculated that school buses in the United States still spew 9 million metric tons of carbon dioxide into the atmosphere each year.
With schools spending about $6,500 on diesel fuel per school bus per year, and about 480,000 school buses in operation across the country, the group calculated that busing students to their classes costs more than $3 billion per year. An installed GreenShield could save $600 in annual gas expenses per bus.
"If they use a GreenShield, school bus companies can charge less for their services, and so less money will have to be spent on school buses, which is less money spent on gas and hopefully more on education," Jonny said.
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23 Comments
Add CommentGood idea to make buses more streamlined but it doesn't look safe.
Reply | Report Abuse | Link to thisCongratulations on a wonderful idea! But in addition, although it will take more time to accomplish, would be to do a redesign of the standard school bus model, so that any new ones built are more aerodynamic in the first place. The new design couldf also incorporate moe child safety features, and perhaps a more efficient engine design as well.
Reply | Report Abuse | Link to thisDear JC please also consider end of life disposal of your invention.
Reply | Report Abuse | Link to thisHey S.A. a picture sure would have been nice...
Reply | Report Abuse | Link to thisThat boy deserves to be congratulated for having interest and ingenuity in the field of fuel savings and dirty emissions reductions, but the concept of a hump over the trucks' or buses' front cabin roof has been for sale in Europe from decades ago, and it must be remembered that at speeds below 44 mph or so, streamlining has little efficacy in improving fuel economy as the drag is not so high, it's hard to imagine an school bus going even that fast. For short range, town confined vehicles, it's possible that nothing compares to hybrids, and there are also lots of low-cost technologies that can improve fuel efficiency and emissions of engines, you can just have a look at SAE.org. The most evident conclusion from this new would be that Johnny Cohen has a good Godfather that cares of him. Salut +
Reply | Report Abuse | Link to thishere's this kid trying to make schoolbuses more efficient and SciAm's idea of streamlining their output is to put an idiotic floating toolbar online. Fire the jerk who ever thought that facetwit floater was a good idea.
Reply | Report Abuse | Link to thisAnyone like that floater?
by no means do i wish to discourage this fine young man for trying . But i agree with #5 .A good idea that was not attempted was the use or natural gas fueling stations for all buses ,trash removal and commercial freight haulers .
Reply | Report Abuse | Link to thisI concur with #5 and #7. It is good to encourage creativity, but I think that the author should have made the point that a 10-20% improvement in virtual wind tunnel tests under unspecified conditions (speed) would not necessarily translate into a 10-20% reduction in fuel consumption in school buses making frequent stops at low speeds and idling in between. I fear that there would be negligible decreases in fuel consumption in school buses. Consider application to Greyhound buses instead. The specific targeting of school buses and the section on "inspirational economics" is suspicious for an attempt to tap a larger market that might be willing to buy these products for the publicity (note this article), regardless of how effective the products are. To improve school bus fuel economy, I tend to agree that research into other fuels or energy sources is more likely to help.
Reply | Report Abuse | Link to thisBuy the buses in Europe, they have highly efficient diesel engines with particulate filters. Their exhaust is not more harmful then that of cars, and they are streamlined safe and comfortable. That thing you have pictured there looks as if it comes out of the mid 1950ies.
Reply | Report Abuse | Link to thisRIGHT ON <lol>
Reply | Report Abuse | Link to thisGreat idea. It is wonderful to see this sort of thinking in the upcoming generation. However, the adults in the room must ask what was the carbon foot print of making the device. If the manufacture of the device creates more emissions than the busses burning their fuel; let em burn it. The problem with trendy solutions is they ignore the total sum of energy economies involved. This thinking pervades the green movement. If you own a Volt or other electric car in a grid powered by coal or other fossil fuel, you would have done far less damage buying an Escalade.
Reply | Report Abuse | Link to thisNo!
Reply | Report Abuse | Link to thisNo!
Reply | Report Abuse | Link to this<g>
Reply | Report Abuse | Link to thisI'd dislike that facetwit "like" button thingie less if it also had a "dislike" button.
And why, if SciAm is so interested in finding out if its readers like something have they not asked their readers if they like that floater? Afraid people would vote against it? Not exactly what I'd consider integrity in a scientific context.
From two measures to two-bit is maybe not as far as one might think?
You know the really stupid part of all this? 30% of the Aero gains to be made occur in the front of a vehicle. The other 70% can be gained in redisigning the rear. Most people, even smart ones, fail to realize this, so it goes on focusing efforts on things that return the least reward.
Reply | Report Abuse | Link to thisVery interesting - I know how important it is for race car tail design but that I saw mainly about downforce. I never realized the relation was this important in road cars. Could you recommend a link to more detail?
Reply | Report Abuse | Link to thisAmazingly, the SA photographer managed not to take a picture of this invention.
Reply | Report Abuse | Link to thisI don't know why the kid is using a traditional commercial route to selling this thing. He needs $30K. I bet he could raise that amount easily on one of the crowdsourcing sites, and just give the things away. That would also accomplish a lot of marketing for him. On the other hand, schools are about the most innovation-proof institutions there are, and they might not install them even if given them for free, and even if there is proof they save money. Maybe the kid should look at other potential markets.
I believe school districts buy new buses only once in a month of Sundays. The current operating stock is decades old. But there is no reason why you can't look at both creating new designs and retrofitting old ones.
Reply | Report Abuse | Link to thisThose are good points, but also consider the really minimal cost of the devices. And they may be useful only for certain districts where buses use highways.
Reply | Report Abuse | Link to thisThere are school districts that are shutting down their buses because they cannot afford the fuel. They do not have money to buy new buses.
Reply | Report Abuse | Link to thisPurchasing new vehicles is not an option for many, if not most school districts. Anyway, why not offer a cheap retrofit option like this one also?
Reply | Report Abuse | Link to thisHow is this going to save fuel for a school bus when most travel at a max speed of 25 mph about 95 % of the time or there in traffic and they stop to pickup kids almost every 1/2 block to block.
Reply | Report Abuse | Link to thisSo they never travel far enough between stops or fast enough to make drag have any effect?
Totally agree the school buses in my suburb travel at max 25 mph the speed limit and they stop every 1/2 block.
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