By Jamie Hyneman
Photographs by Mark Richards
I'm really big on electric vehicles because the total amount of fuel consumption involved is much less than what gas vehicles consume thanks to the efficiencies involved in a power generating plant. But there's a lot of talk out there that electric vehicles just don't perform as well as their gas counterparts—and, because we want to keep the planet intact, it sounded like a good myth to bust. So we decided to put gas and electric models of compact cars, ATVs, motorcycles and go-karts head-to-head on the track and the road to figure out if electric could hold its own.
We started by pitting two average compact cars—one with a standard gas engine and an electric that had been converted from gas in someone’s garage—against each other on a country road. The gas car did what every gas car does: It was peppy and got me where I wanted to go. The home-built electric eventually got up to highway speeds on the flat or downhill, but I had to stop on a medium steep hill to allow cameras to reset for my arrival, and the car just didn’t have the power to get up the hill without a running start. Kudos to the builder, though, who used lead acid batteries and other components that were easy to find. He made a car that would get you to the store or down the highway, but the range was limited and you’d pretty much be the slowest thing on the road.
Then things picked up a bit. A little over a year ago I was approached by a company called Barefoot Motors to help develop an electric ATV. My first reaction was that this was a recreational vehicle and, while worth doing, it wouldn’t make a big impact if some kids were using electric instead of gas ATVs to fool around in the backyard.
Then Barefoot showed me the numbers. There are millions of ATVs out there, and a major portion are used for agriculture and forestry. Every hour that a gas ATV is running, it’s putting out as many pollutants as four modern cars because the engines don’t have the same pollution restrictions. An electric ATV could be charged on the grid at a fraction of the pollution and cost associated with gas ATVs, and it would be much quieter, too. So we took a week and built one using a pre-existing, heavy-duty ATV. We removed all the engine-related stuff and mounted a 45-hp AC induction motor right to the torque converter. AC motors can be very efficient, but may not have as much bottom-end torque as a DC motor, so the torque converter was just the ticket. We paired it with an Alltrax speed controller already made to accommodate regenerative braking. We used Thundersky lithium-iron phosphate batteries to power the ATV, and that, combined with a very efficient motor and speed controller system, allowed us to cut down from the 600-pound weight of the gas version to 500 pounds on the electric one—same make and model chassis, same horsepower.
Then we took the electric Model One ATV and a traditional gas ATV out to a motocross track to see how our electric performed—and it won by a hair, mainly due to the motor’s high bottom-end torque and the easier maneuverability due to the lighter weight. (I suspect the gas one would win in a drag race, but that’s not what ATVs are used for, is it?)
We also managed to get access to some very fast electric and gas motorcycles, which we tested at Infineon Raceway in Sonoma, Calif. The gas motorcycle, a modified Harley Dragster, went against an electric Killacycle on a quarter-mile dragstrip. The Killacycle also used A123 Systems batteries; interestingly, the bike had the same Advanced Direct Current (DC) 75-volt motor that I used on the go-karts—only there were two of them. I thought I was pushing it by pumping 125 volts through the motor, but these guys were running them at over 500 volts. Those motors aren’t made for that, and it caused problems: There were a couple runs that were right about the same as the gas bike, and the Killacycle welded the motorcycle’s commutator into one solid lump. The builder seems happy with the battery system, though, and intends to use an AC induction motor as soon as he finds the right one. There are no brushes to wear out, and they can get efficiencies of up to 95 percent.
Finally, we got to the cars—not homebuilt ones, either. We pulled in an electric car named the X1 made by Ian Wright of Wrightspeed, Inc., from Silicon Valley, Calif. The car does 0 to 60 in 3.07 seconds. It’s a two-seater with an open cockpit—more of a race car than something you would commute with, but Ian drove it to the track on the highway, and every last thing about it was refined and all business. We raced it against a Ferrari on the quarter-mile; it cleanly and quietly crossed the finish line first. The X1 currently has a range of 100 miles of average highway driving and uses lithium polymer batteries, which are another variation of the lithium approach, and a good one—except that a battery change runs you about $40,000. The X1 in production is expected to cost about $200,000 when it comes out, and if it’s anything like Ian’s first one, it will be a car to keep your eye on.
Our tests convinced me that if you can go electric, you should. Taking off across the country might not be practical, but if you’re commuting, you can plug in the car, get in, go to work and then plug it in again. The two- and four-cycle gas engines used on ATVs and go-karts are extremely polluting. With electric vehicles, you’re dealing with a very small fraction of the fuel consumption and pollution because you’re using the power grid.
Besides almost zero emissions, electric vehicles also have some very distinct advantages: An electric ATV is quiet, healthier to have around crops, and you don’t need it to go 300 miles on a charge. Barefoot’s prototype is running 2.5 hours of average use on a charge and is back to 80 percent charge over a lunch break, which is more than adequate run time on a farm or vineyard. Our highways and neighborhoods will be quieter and cleaner with electric cars and motorcycles on them.
Building an electric go-kart or ATV is not any more difficult than making a radio-control electric car. Sure, we’re using welders instead of pre-made plastic parts, but you’ve got an electric motor, a bank of batteries and a speed controller. Look at your racing RC toys—it’s the same thing. The home-built electric car we tested had serious limitations, but I think I could build one that doesn’t have those problems. I fully intend to make a full-size electric car; I figure it’d take about $28,000 worth of components for a plus-300-mile range. It should take me about a week or two to build—tops.
Original here
I'm really big on electric vehicles because the total amount of fuel consumption involved is much less than what gas vehicles consume thanks to the efficiencies involved in a power generating plant. But there's a lot of talk out there that electric vehicles just don't perform as well as their gas counterparts—and, because we want to keep the planet intact, it sounded like a good myth to bust. So we decided to put gas and electric models of compact cars, ATVs, motorcycles and go-karts head-to-head on the track and the road to figure out if electric could hold its own.
We started by pitting two average compact cars—one with a standard gas engine and an electric that had been converted from gas in someone’s garage—against each other on a country road. The gas car did what every gas car does: It was peppy and got me where I wanted to go. The home-built electric eventually got up to highway speeds on the flat or downhill, but I had to stop on a medium steep hill to allow cameras to reset for my arrival, and the car just didn’t have the power to get up the hill without a running start. Kudos to the builder, though, who used lead acid batteries and other components that were easy to find. He made a car that would get you to the store or down the highway, but the range was limited and you’d pretty much be the slowest thing on the road.
Then things picked up a bit. A little over a year ago I was approached by a company called Barefoot Motors to help develop an electric ATV. My first reaction was that this was a recreational vehicle and, while worth doing, it wouldn’t make a big impact if some kids were using electric instead of gas ATVs to fool around in the backyard.
Then Barefoot showed me the numbers. There are millions of ATVs out there, and a major portion are used for agriculture and forestry. Every hour that a gas ATV is running, it’s putting out as many pollutants as four modern cars because the engines don’t have the same pollution restrictions. An electric ATV could be charged on the grid at a fraction of the pollution and cost associated with gas ATVs, and it would be much quieter, too. So we took a week and built one using a pre-existing, heavy-duty ATV. We removed all the engine-related stuff and mounted a 45-hp AC induction motor right to the torque converter. AC motors can be very efficient, but may not have as much bottom-end torque as a DC motor, so the torque converter was just the ticket. We paired it with an Alltrax speed controller already made to accommodate regenerative braking. We used Thundersky lithium-iron phosphate batteries to power the ATV, and that, combined with a very efficient motor and speed controller system, allowed us to cut down from the 600-pound weight of the gas version to 500 pounds on the electric one—same make and model chassis, same horsepower.
Then we took the electric Model One ATV and a traditional gas ATV out to a motocross track to see how our electric performed—and it won by a hair, mainly due to the motor’s high bottom-end torque and the easier maneuverability due to the lighter weight. (I suspect the gas one would win in a drag race, but that’s not what ATVs are used for, is it?)
We also managed to get access to some very fast electric and gas motorcycles, which we tested at Infineon Raceway in Sonoma, Calif. The gas motorcycle, a modified Harley Dragster, went against an electric Killacycle on a quarter-mile dragstrip. The Killacycle also used A123 Systems batteries; interestingly, the bike had the same Advanced Direct Current (DC) 75-volt motor that I used on the go-karts—only there were two of them. I thought I was pushing it by pumping 125 volts through the motor, but these guys were running them at over 500 volts. Those motors aren’t made for that, and it caused problems: There were a couple runs that were right about the same as the gas bike, and the Killacycle welded the motorcycle’s commutator into one solid lump. The builder seems happy with the battery system, though, and intends to use an AC induction motor as soon as he finds the right one. There are no brushes to wear out, and they can get efficiencies of up to 95 percent.
Finally, we got to the cars—not homebuilt ones, either. We pulled in an electric car named the X1 made by Ian Wright of Wrightspeed, Inc., from Silicon Valley, Calif. The car does 0 to 60 in 3.07 seconds. It’s a two-seater with an open cockpit—more of a race car than something you would commute with, but Ian drove it to the track on the highway, and every last thing about it was refined and all business. We raced it against a Ferrari on the quarter-mile; it cleanly and quietly crossed the finish line first. The X1 currently has a range of 100 miles of average highway driving and uses lithium polymer batteries, which are another variation of the lithium approach, and a good one—except that a battery change runs you about $40,000. The X1 in production is expected to cost about $200,000 when it comes out, and if it’s anything like Ian’s first one, it will be a car to keep your eye on.
Our tests convinced me that if you can go electric, you should. Taking off across the country might not be practical, but if you’re commuting, you can plug in the car, get in, go to work and then plug it in again. The two- and four-cycle gas engines used on ATVs and go-karts are extremely polluting. With electric vehicles, you’re dealing with a very small fraction of the fuel consumption and pollution because you’re using the power grid.
Besides almost zero emissions, electric vehicles also have some very distinct advantages: An electric ATV is quiet, healthier to have around crops, and you don’t need it to go 300 miles on a charge. Barefoot’s prototype is running 2.5 hours of average use on a charge and is back to 80 percent charge over a lunch break, which is more than adequate run time on a farm or vineyard. Our highways and neighborhoods will be quieter and cleaner with electric cars and motorcycles on them.
Building an electric go-kart or ATV is not any more difficult than making a radio-control electric car. Sure, we’re using welders instead of pre-made plastic parts, but you’ve got an electric motor, a bank of batteries and a speed controller. Look at your racing RC toys—it’s the same thing. The home-built electric car we tested had serious limitations, but I think I could build one that doesn’t have those problems. I fully intend to make a full-size electric car; I figure it’d take about $28,000 worth of components for a plus-300-mile range. It should take me about a week or two to build—tops.
Original here
No comments:
Post a Comment