Print 64 comment(s) - last by Zirconium.. on May 29 at 8:19 AM

Ford Escape Hybrid
Hybrid fever strikes New York City

Given the stop and go nature of traffic in New York City, the promise of increased fuel efficiency from hybrids is too good to pass up. Mayor Michael Bloomberg announced yesterday on the "Today" show that every yellow cab will be a hybrid by the year 2012.

There are roughly 13,000 taxis roaming city streets (90 percent of which are gas guzzling Ford Crown Victorias). According to Bloomberg, 20 percent of the existing yellow cab fleet will be replaced each year until all are running on hybrid power. Currently, there are only 375 hybrid taxis on the road in NYC.

"There's an awful lot of taxicabs on the streets of New York City obviously, so it makes a real big difference," said Bloomberg. "These cars just sit there in traffic sometimes, belching fumes; this does a lot less. It's a lot better for all of us."

There are currently eight vehicles on the city's "approved" list when it comes to hybrid vehicles to be used as yellow cabs: the Ford Escape Hybrid; the Honda Accord Hybrid and Civic Hybrid; the Lexus RX400h; the Saturn Vue Green Line; and the Toyota Highlander Hybrid, Camry Hybrid and Prius. As more manufacturers roll out fuel efficient hybrids, the number of possible candidates is sure to increase. Vehicles like the Saturn Aura Green Line and rumored Ford Fusion hybrid are likely to join the list.

Ford Crown Victorias are rated at 15 MPG in city driving. A Ford Escape Hybrid, however, is rated at 31 MPG in the city according to the new 2008 EPA estimates. Hybrids like the Camry and Prius are even more fuel efficient at 33 MPG and 48 MPG respectively.

The Ford Escape Hybrid has already seen extensive use in San Francisco. Taxi operators reported on their vehicles once the 100,000 mile mark was surpassed. According to the operators, fuel savings compared to the Crown Victoria were between $20 to $31 per shift. Air conditioning costs were also roughly half that of Crown Victorias. Another plus was that the brakes lasted twice as long due to the hybrid system's regenerative braking feature taking a load off the traditional braking system. Most importantly, there were no complaints of poor rear legroom from passengers.

Yahoo Inc. has already committed to donate 10 Ford Escape Hybrid taxis according to Bloomberg.

When all is said and done, the switch to a completely hybrid yellow cab fleet will save each taxi operator over $10,000 USD per year in fuel costs while also cutting total carbon emissions by 200,000 tons per year.

Comments     Threshold


RE: Probably not a bad move
By Hoser McMoose on 5/23/2007 5:15:56 PM , Rating: 2
Initially it might seem quite odd, but the idea actually works fairly well and has been proven in trains at least for some time.

The problem with an internal combustion engine in a car is that it isn't very good when you operate it outside it's peak rev range. A lot of the complexity and inefficiencies of the engine are built around solving this.

The Volt simplifies things, the engine runs at only a very specific RPM rate. This allows you to greatly simplify the design of the engine and make it much more efficient at the same time. They then also take out the entire linkage to the wheels and remove the need for a transmission. Regenerative breaking is still used, as in current hybrids, and they also add the option to plug the car in to recharge the batteries.

Does it work? Well according to GM's numbers, yes! Ignoring the plug-in aspect, they're claiming about 970km (600 mile) from a 45L (12 gallon) tank on the highway. That works out to a rather impressive 4.6L/100km (50mpg) on a car with a 160 horsepower engine. This puts it right on par with the Prius which has only a 110hp engine.

RE: Probably not a bad move
By Hoser McMoose on 5/23/2007 5:27:12 PM , Rating: 2
A couple additional points with the Volt. In the early form they're planning on using a gasoline/ethanol flex-fuel generator. Part of the beauty of this setup though is that the internal combustion engine connected to the generator can be easily swapped.

Dropping in a really nice tiny turbo-diesel engine would REALLY boost the potential for this vehicle. The fuel consumption could easily drop by 35-35% (on a by-volume basis), while they could avoid a lot of the air pollution problems caused by diesel engines. A lot of the air pollution from diesels (vs. gasoline engines) can be avoided by running the engine at a constant RPM.

Another, slightly more out-there, option would be an HCCI engine. This is a gasoline engine that uses compression for ignition instead of a spark. The idea is not entirely unlike diesel engine and benefits from a lot of the same fuel efficiency benefits, but it is not the same process. This hasn't been implemented in vehicles yet because, again, there are problems when running at variable RPMs. Fixing the engine to a single constant RPM would avoid those problems allowing for an even more fuel efficient design. Beyond being just fuel efficient though, HCCI engines also do a VERY good job at getting complete combustion of all fuel. This results in significantly less air pollution coming out the tailpipe.

And if you wanted to be REALLY wacky (and somewhat pointless) you could drop in a fuel cell and run the thing off hydrogen. In fact, this is exactly how all hydrogen fuel cell vehicles are likely to operate, though that's likely to result in lower efficiencies (well to wheel) as compared to even the plain old gasoline engine of the prototype.

RE: Probably not a bad move
By Zirconium on 5/29/2007 8:19:48 AM , Rating: 2
You are correct. Most of the energy wasted in a car comes during acceleration, when the engine is not running within its optimum range, and during breaking, when energy is just flat out lost to heat in the breaks. The Volt concept attempts to solve these using constant rev ranges and regenerative breaking. The option to plug in is very intriguing as well, since a lot of people that I know tend to do most driving within a 5 mile radius (i.e. to the grocery store and back).

