Ford’s New Hybrid Escape
Trust Me: You Are Going To Want One Of
By Perry Hicks
This summer, Ford Motor Company will schedule JOB1 for the world’s first hybrid gasoline-electric sport utility vehicle. Based on the hot selling Escape platform, the Escape Hybrid will likely be available in dealer show rooms by fall. The price: $26,380 for the front-drive only model and $28,005 for four-wheel drive. Those pricesare $3,300-$3,425 over a 3.0 Liter Duratec V-6 Escape XLT. Ford reports that the delivery charge will be about $590.00.
Softening the hybrid premium is the "Clean Fuel Vehicles Tax Credit” of $1,500. That tax credit can be taken whether one itemizes their taxes or takes the standard deduction. If that isn’t enough, consider this: The 2005 Escape Hybrid is rated at a whopping 40mpg in city driving! That is 70 percent better mileage than the V-6 Escape for which the hybrid was benchmarked.
In order to demonstrate hybrid fuel efficiency in a real world environment, Ford put on the “Manhattan on a Tank of Gas” event, driving an Escape Hybrid continuously for 37 hours in what is arguably America’s worst traffic. Escape Hybrid covered 576 miles on a single 15 gallon tank of gasoline. Do the math; that comes to over 38 mpg.
"We beat our own best estimates," said Mary Ann Wright, Ford’s Director of Hybrid Vehicle Programs. "We set out to drive at least 500 miles of city traffic. The Escape Hybrid surpassed the ultimate urban driving test proving it is the cleanest and most fuel-efficient SUV on the planet."
Escape Hybrid is indeed clean having 97 percent less hydrocarbon and oxides of nitrogen emissions than conventional vehicles meeting the nationwide Tier 1 standard. That's clean enough to qualify the Escape Hybrid for the stringent Advanced Technology Partial Zero Emissions Vehicle (AT-PZEV) standards. Escape Hybrid also produces only half the carbon dioxide of a conventional vehicle. Carbon Dioxide is the gas attributed to the green house effect claimed to be causing global warming.
Driving Escape Hybrid
However, man (or woman for that matter) doesn’t live by partial zero emissions alone. No matter how clean or miserly, a vehicle must be both practical and pleasant to drive. This is where the Escape Hybrid shines and why you will really, really want to own one.
It simply drives great.
Unlike other high fuel mileage or super clean running vehicles, Escape Hybrid has power. In fact, it was designed to have equivalent acceleration performance to its conventional V-6 powered counterpart. Stomp the accelerator pedal and Escape Hybrid will scratch off and push you pleasantly back into the seat.
It is also unbelievably smooth. At speeds under 25 mph Escape Hybrid is propelled solely by electric propulsion. At 35 mph, power is transferred seamlessly to it 2.3 Liter I4 Atkinson Cycle engine. Throttle response is excellent without any of the golf cart feel I have experienced driving the Ranger Electric pickup truck.
Aiding this smoothness is electric power assisted steering and an electronically controlled continuously variable “automatic” transmission (eCVT). Shifts are never felt because there are none. The eCVT has no belts, either. Engine power is delivered to both the drive wheels and the generator through a planetary gear set. (See the Tech-Talk section for a detailed explanation.)
Also, the steering never makes hydraulic hissing and groaning noises because there is no leaking, moaning or groaning hydraulic power steering pump. An electric motor provides power assist whether the gasoline engine is running or not.
Because my example ride was a 3P prototype, my driving impressions had to be limited to a large but empty parking lot. However, Escape Hybrid handled well in all maneuvers and the electric steering did not have the weird responses to driver inputs that have been criticized in other manufacturer’s vehicles.
All cars and trucks are a compromise of diametrically opposed design factors such as power and performance vs. safety and economy. Escape Hybrid is optimized not for the highway but for the urban jungle. Highway fuel mileage is actually lower (30mpg) than city driving. This is because the bulk of Escape Hybrid’s efficiency comes from the regenerative braking system and automatic engine shut down features.
Conventional vehicles are stopped by friction brakes which convert energy of motion into heat. Escape Hybrid has a regenerative braking system that slows the SUV by converting some of that energy of motion to electricity and storing it in a battery pack where it can be reused to launch or accelerate the vehicle. Also, the I 4 Atkinson engine can be automatically shut down thus avoiding the fuel waste and tailpipe emissions during long idling periods.
In fact, when you “start” Escape Hybrid, the engine may or may not crank. Unlike the Toyota Prius that has a special starting procedure, you simply turn Escape Hybrid’s key to the “start” position and release it; put the console mounted selector in a forward or reverse range, release the parking brake, step on the accelerator pedal and go. If the battery pack is sufficiently charged, the engine will not be started until Escape reaches 35mph.
One of the first things you will notice beyond smoothness, is the disconnect between engine speed and vehicle speed. On my initial drive, the gasoline engine came to life on startup but its speed did not track road speed. On return to the garage, the engine “stalled” just as I came to a stop- at least that was my initial thought. What had happened was the battery pack came up to sufficient charge to propel the vehicle without aid from the gasoline engine, so the engine was simply shut off.
As one might expect, running air conditioning or defrost mode will have a greater impact on Escape Hybrid fuel economy because the AC compressor is gasoline engine driven.
Surprisingly, the gasoline engine and motor-generator will never charge the 330 volt battery pack to 100 percent. Remember that Escape Hybrid has regenerative braking. If we are going to recover energy we must have some place for it to go. The max charge may only reach as high as 60 percent. There is some speculation that brake pads might last as long as 100,000 miles of city driving.
The 330 volt battery pack is called the traction battery and it is located in the floor of the cargo area. The pack contains 250 nickel metal hydride cells (NiMH) connected in series to deliver up to 181 amps under hard acceleration. Terminal voltage under high load may drop as low as 216 volts; that comes to 39kW of power. The traction battery not only propels the Escape Hybrid at lower speeds it also cranks the engine.
As you might suspect, jump starting a 330 volt battery could be an electrifying thrill. In order to make emergency jumping safe, a special jump start switch and electronic module steps 12 volts up to 330 volts. Because the Escape Hybrid also has a conventional 12 volt battery to run lights and accessories, the emergency jump could come from itself.
The engine is based on the familiar Escape 2.3 Liter I 4 engine but with the Atkinson Cycle extended intake valve duration. By using the Atkinson cycle, fuel consumption is reduced 7-10 percent. Engine speed is controlled by an electronically controlled throttle plate (drive by wire).
While efficient, Atkinson engines do not develop torque at low rpm. Thus, Escape Hybrid’s engine idles at about 1200 rpm. Power is delivered to the eCVT transaxle not through a heavy torque converter, but through a manual clutch disk and pressure plate. The clutch has no provision for actuation but is simply there to improve noise, vibration, and harshness characteristics (NVH) by absorbing cylinder firing impulses.
Also, improved NVH is facilitated by an electronically switched powertrain (engine-transmission) mount. As engine speed and load changes, the mount can change the amount of movement allowed and at the same time limit the amount of engine vibration coupled to the vehicle body.
The Aisin AW eCVT transaxle has no pulleys or belts but instead incorporates a single planetary gear set. The gasoline engine is coupled to the planetary carrier and the 330volt 65kW (87 hp) traction motor is coupled to the ring gear. The smaller, 36kW 48hp motor generator is connected to the sun gear. It is capable of starting the engine in as little as 400 milliseconds.
Power will not flow through a planetary gear set without one of the three members (sun gear, ring gear, or planetary carrier) being held stationary. In a conventional automatic transmission, the necessary component is usually held by either a mechanical one way clutch or a brake band (increasingly the brake band is replaced by a hydraulic holding clutch.) In the Escape Hybrid, this motor generator slows the sun gear when it is producing electric power. Thus, by continuously varying the motor generator output, the effective “gear” ratio can be made continuously variable.
[Note: Mechanical Tekies might realize this “drive-the- carrier, hold-the- sun, output-the-ring-gear” as an overdrive configuration. This would be true if the sun were held stationary. However, because the motor generator holding force allows sun gear rotation, the effective ratio can span anywhere from reduction all the way to overdrive. Hence, the eCVT is a continuously variable automatic transmission.]
One interesting feature of the eCVT is that it has no reverse. That’s right, no provision for the gasoline engine to power Escape backwards. Reverse is facilitated by the electric traction motor alone.
Rumor on the street is that Escape Hybrid is using the hybrid system out of Toyota’s Prius. This is absolutely false. Ford Motor Company developed and engineered the hybrid system and possesses 100 patents on the design. The Atkinson engine is an adaptation of the 2.3 Liter Duratec I 4 found in Ranger, Escape, and 2005 Focus. The eCVT is manufactured by Aisin AW specifically for Escape.
Of the 351 patents covering the hybrid drivetrain, Ford did feel compelled to pay license fees to Toyota on 21 of them. This was done simply to avoid any patent infringement controversies.
NiMH batteries are sensitive to both heat and cold. While the traction battery can be heated by an electric element, cooling is another matter. The traction battery has is own auxiliary AC unit located in the left rear corner of the cargo compartment. The fresh air intake for the auxiliary unit is a slot in the left rear “window.”
Power flow into or out of the traction batteries is monitored by a small charge-discharge gauge located to the left of the instrument panel. An optional navigation radio displays hybrid information on an energy flow screen. Purely for informational purposes, riders can see when gasoline engine power is propelling Escape, charging the battery, being assisted by the traction motor, or regenerative braking is taking place.
The 4 wheel drive version uses Ford’s new automatic Intelligent 4WD System. Unless needed, Escape remains in front drive mode. If needed, a computer controlled clutch delivers just the right amount of torque to the rear wheels. The benefit is that parking lot maneuvers are smooth as a front drive car but maximum traction is equivalent to a “locked” 4 X 4 system.
The computer algorithm for Intelligent 4WD monitors all four wheels to not just detect wheel slippage, it can actually predict it. There is no on/off or mode switch as with the current Control Trac II. Intelligent 4WD is claimed to improve fuel economy by .2 mpg.
Escape Hybrid also has a special warranty package. Beyond the 3 year/36,000 mile bumper to bumper warranty to include the engine, the hybrid components are warranted for 8 years/100,000 miles. In the Green States of California, Massachusetts, Maine, New York, and Vermont the traction batteries are warranted for 10 years/150,000 miles.
ESCAPE HYBRID PRICING
2005 Escape Hybrid Optional Equipment, Packages, and Pricing
Appearance Package includes: A-Gloss Silver Metallic fascias, body side cladding and wheel lip moldings, and A-Gloss body color door handles and liftgate garnish. A monochromatic look is achieved when Silver Clearcoat Metallic is ordered with Appearance Package.
Leather Comfort Group includes: leather-wrapped steering wheel and leather trimmed seats.
Safety Package includes: The Safety Canopy™ side air curtains and front side impact air bags are offered in combination to make up the Safety Package. This package provides added side impact, head and rollover protection.