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Escape Hybrid

Written by Ed Sanow

The Escape Hybrid is powered by a 2.3L 4-cylinder gasoline engine and a 70-kilowatt electric motor. The Escape Hybrid can run on the electric motor alone, the gasoline engine alone or a varying combination of these two, whatever gives the most economical operation. The Escape Hybrid never needs to be plugged in.

This electric traction (or drive) motor is what makes the Escape Hybrid a “full” hybrid. This is in contrast to a “mild” hybrid, a vehicle that merely shuts off as you coast to a stop and at idle but does not have an electric motor to assist in driving the vehicle.

Even among “full” hybrids, two sub-categories exist. In the system used by the Escape Hybrid and Toyota Prius, the electric motor without the gas engine actually propels the vehicle at low speeds. This electric motor will also kick in to help the gas engine when more acceleration is needed. In the system used by the Honda Civic Hybrid and Honda Insight, the electric motor helps the gas engine under heavy demand but will not propel the vehicle by itself.

Unique Technology

The Escape Hybrid has a number of unique features. First, it uses a special version of the basic 2.3L 4-cylinder engine with the Atkinson-Miller combustion cycle instead of the traditional Otto combustion cycle. Second, the Escape Hybrid has an electronically controlled, Continuously Variable Transmission (eCVT). This is connected to both the gasoline engine and the electric drive motor.

Third, the mid-size SUV has a massive starter motor for the engine. The gas engine automatically shuts off at lower speeds and at a stop. This high voltage starter motor restarts the engine in 0.4 seconds. Fourth, the Escape Hybrid uses a regenerative braking system. Somewhat like engine braking, this system converts braking energy into electricity and stores it in the High Voltage battery.

Fifth, the Escape Hybrid has a massive, 330-volt Nickel Metal Hydride, High Voltage battery in the rear of the vehicle that powers the electric drive motor and the electric starter motor. Sixth, the Escape Hybrid has hydro-electric, power-assisted steering and brakes. It does not rely on the engine to turn a pulley for the power steering, and does not use engine vacuum to power the brakes. You still have both power steering and power brakes with the gasoline engine shut off.

Seventh, and the very heart of the hybrid drive system, is the electric drive (traction) motor. The Escape Hybrid can be driven at low speeds by the electric motor alone. It can also use this electric motor to assist the gasoline engine under heavy acceleration. This permanent-magnet, electric motor produces the equivalent of 94 hp! The electric motor is the most efficient at low speed and under low loads...exactly where all gasoline engines are the least efficient.

Finally, the Escape Hybrid we tested came with the full-time AWD, i.e., “Intelligent 4WD” single-range system. The Escape operates in front-wheel drive until the front wheels lose traction. When that happens, a computer-controlled clutch transfers some power to the rear wheels. The Escape Hybrid may be the perfect light-duty, enforcement vehicle for lower speed and stop-go patrol areas like college campuses, parking enforcement, beach patrol, heavily urbanized areas, retirement communities, etc. At the retail level, the upcharge for the hybrid package is $3,500.

The Escape Hybrid has an eight-year and 100K-mile warranty on hybrid components and a standard three-year and 36K-mile warranty on the rest of the vehicle. In the “green states” of CA, MS, MA, VT and NY, the hybrid warranty is 10 years and 150K miles. The 2.3L Escape Hybrid is capable of towing a 1,000-pound trailer.

The Escape Hybrid qualifies in California as an Advanced Technology Partial Zero Emissions Vehicle (AT-PZEV), one of the strictest emissions certifications. At the Federal level, it qualifies as Tier 2, Bin 4 emissions standards.

Hybrid Operation

The hybrid operation has four basic stages aspects: 1) Start-Stop, 2) Electric Drive, 3) Regenerative Braking and 4) Cruise with Electric Power Assist. The Escape Hybrid is powered by both the gasoline engine and the electrical motor most of the time. At almost all speeds, the electric motor continues to help the gasoline engine. During constant cruising or light throttle, the motor helps the engine a little. During heavy acceleration, the motor helps the engine a lot.

Under very light throttle, the electric motor will move the Escape Hybrid up to 25 mph before the gasoline engine kicks in. The gas engine generally shuts off at around 30 mph while coasting to a stop. Under normal to heavy throttle positions, the gasoline engine will kick in immediately to move the vehicle. You can feel the Escape transition from electric mode to hybrid mode (gas engine running). However, the transition is so smooth and so quiet, you must pay attention to notice it.

Much more than very slow and gradual accelerator pressure and the gas engine starts. To keep from being run over in normal stoplight-controlled traffic, you have to give the Escape Hybrid enough throttle that the gas engine starts.

Continuously Variable Transmission

The eCVT is itself a wonder of both electronics and mechanics. (See the Jan-Feb 2005 issue of Police Fleet Manager.) The powertrain control module puts the engine at whatever speed is ideal for either power or economy and the eCVT makes up the difference.

Give the Escape Hybrid full throttle and three things instantly happen. First, the eCVT transitions to a lower gear ratio depending on exactly how much throttle you have given it and how fast the vehicle is already going. This is not a specific gear ratio. It constantly changes.

Second, the engine immediately revs up to 6,000 rpm. It doesn’t wait for the car to catch up, it goes to 6,000 rpm right away. The engine speed (tachometer) has seemingly little to do with the vehicle speed. If you were not watching the tachometer, your first sensation would be the engine seems to speed up faster than the vehicle is accelerating. Exactly so. Third, the electric motor kicks in with its maximum torque. The resulting performance is brisk, but the way it delivers that performance is very different from what most drivers are used to.

The Escape Hybrid uses a High Voltage battery pack that is actually made up of 250 D-cell batteries wired in series. Once the gasoline engine is warmed up and the High Voltage battery is fully charged, the Escape Hybrid engine will shut off at low coast speeds, at idle, and at very low driving speeds.

Depending on the ambient temperature and the High Voltage battery’s state of charge, the gasoline engine may automatically start, or stop, or remain running, 1) the High Voltage battery needs re-charged, 2) the acceleration demands exceed the electrical motor capability, 3) the ambient temperature is very hot or very cold, and 4) certain HVAC settings are selected. If the High Voltage battery is very hot or very cold, the gasoline engine will operate more than under normal temperature conditions. The economic advantages of the hybrid system are reduced under weather extremes.

Interior Room

The Escape is clearly a mid-size SUV, and considering the rest of the Ford SUV fleet, is probably best described as a small SUV. Obviously, you simply cannot haul the same amount of emergency gear in the Escape as you would in an Explorer. Room for a canine? Yes. Room for SWAT gear, cave and cliff rescue, SCUBA or rural enforcement? Probably not. Like the Explorer, the Escape Hybrid has a combination lift gate and split window. Either can be opened independently of the other.

The Escape Hybrid seating room will be a significant challenge for many patrol officers wearing the standard duty belt. The interior passenger room is OK, similar to a mid-size sedan. Like some mid-size sedans, the Escape’s interior room is also limited by a floor shifter and center console. And like most retail vehicles with a center console, fastening the seat belt is a real hassle. Doing that in the Escape while wearing a gunbelt takes a contortionist. It is extremely unhandy.

Oddly, this limited space is even further taken up by an old-fashioned, emergency brake lever on the passenger side of the center console. That is great for a Mini Cooper but quite out of place in the Escape.

The seats are wide enough, almost in spite of the center console, and they have good side bolsters. However, the seats are fairly short! They end mid-thigh and at the lower shoulder blades. These seats were not taken from the excellent Explorer!

The Escape Hybrid allows excellent visibility in nearly all directions. The vehicle sits up high, of course, and is very easy to see to the front, rear, out both sides, and through the A and B-pillars. The outside mirrors are very good and the blind spots are very small.

Dash Display

The dash has four easy-to-read gauges. In addition to the speedometer and gas gauge, the Escape Hybrid has a unique tachometer. The tach is the fastest and most reliable way to see if the gasoline engine is actually running or not.

A green section of the tach dial at a reading less than zero rpm is labeled EV (electric vehicle). With the needle in this green zone, the gasoline engine is off and the Escape Hybrid is running entirely on battery power. Also on the dash is an energy flow meter. The needle goes back and forth between Assist and Charge as electrical energy is drawn from, or returned to, the High Voltage battery.

In the center of the dash, between driver and passenger, is an Energy Flow Screen. This provides a graphical display of how the power is used or applied during the operation. The Energy Flow Screen has seven different displays. The Engine Power icon tells how much power is provided to the wheels strictly by the gasoline engine. It varies from zero to a thin arrow to a thick arrow as the engine contributes more power.

The Engine icon itself is highlighted in orange but only when the gasoline engine is running. Generator Power represents how much power is generated by the engine for use by the High Voltage System or used by the High Voltage system to start or control the engine.

The HV battery icon is the High Voltage battery. The state of charge of this battery pack is shown on the display. Battery Power is how much power the High Voltage battery is providing to accelerate (discharge) or how much power is delivered back through the motor to the battery (charging). This is exactly the same information from the Assist-Charge gauge on the main dash.

The Electric Motor icon represents the hybrid electric motor. Motor Power shows by a thin or thick line how much power the electric motor is delivering to the drive wheels (accelerate) or how much power is being delivered back to the battery (regenerative braking).

The same display panel on the dash also has the Fuel Economy Screen. This has three pieces of information. First, the instantaneous fuel economy is displayed as a rising and falling bar. It varies from zero mpg to over 50 mpg.

Second, average fuel economy is displayed as a bar across the display containing an mpg value. Third, the display includes a one-minute, running average graph, which flows from left to right. This shows the fuel economy over the past 15 minutes as a rolling graph.

The Escape Hybrid has auxiliary 12-volt power outlets, of course. However, it also has a 110-volt AC (household current) plug-in on the center console. This is used for powering small electrical devices that use only 150 watts, i.e., a 150-watt light bulb.

This circuit will NOT power motor-driven devices or products that require an extremely stable power supply. Think in terms of very light power draws. It did operate the 110V power supply for a laptop computer. This 110-volt outlet is an option.

Driving Impressions

We drove the Escape Hybrid in the weather typical of winter in the Midwest: dry roads, wet roads, light snow cover, heavily drifted snow, and sleet- and ice-covered roads. We put 750 miles on the Escape Hybrid and enjoyed every minute of this modern marvel. It is a little small, and doesn’t quite deliver the advertised EPA numbers, but for what it can do, it does extremely well.

Without the tach and dash-mounted display, most drivers would not be able to tell when the engine was running, when it shut off, or when it started again. All of the transitions in power management are surprisingly smooth. When the gasoline engine shuts off as the vehicle approaches a stop, it is absolutely transparent. You still have power brakes, power steering and full HVAC. If you are paying attention, you can feel the gasoline engine kick in.

Our test vehicle had the full-time, all-wheel drive. The “Intelligent 4WD” worked extremely well as we drove down snow-drifted roads on mere All-Season tires. It handled even the odd, split-mu combination of 12 inches of snow on the right wheels and hard-packed snow over ice on the left wheels. The Escape Hybrid has excellent brakes and surprising straight-line performance. The 50 mph to 80 mph passing performance is excellent. It easily keeps up with traffic of all speeds and accelerates very well from a stop or on an entrance ramp.

The Escape Hybrid does not accelerate quite as fast as the 3.0L V-6 Escape, 10.8 seconds to 60 mph versus 8.8 seconds. However, it gets better actual mileage than either the 3.0L V-6 or the standard 2.3L I-4. The Escape Hybrid is speed-limited to 102 mph.

The Escape Hybrid is definitely not a good choice for high-speed or pursuit-style emergency driving. It is a retail SUV with a soft suspension and lots of body roll. The Escape Hybrid should not be driven aggressively!

Performance-Economy Compromise

The hybrid operation is a complex and expensive compromise to give both economy and performance. An overall less expensive alternative may be to simply get the 4-cylinder engine. While significantly lower performance, the 4-cylinder has virtually the same fuel economy under some driving situations.

The Escape Hybrid has been casually generalized as having the performance of a 3.0L V-6 and the fuel economy of a 2.3L I-4. More correctly, the Escape Hybrid has almost the same acceleration as the 3.0L V-6 Escape. And, EPA estimates aside, the Escape Hybrid actually gets better mileage than the I-4 under some driving situations and a lot better mileage under very specific situations.

Like all hybrid vehicles, the fuel economy from the Escape Hybrid is extremely dependent on the driving pattern or driving circuit. Not necessarily driving style, but instead, the exact path the vehicle is driven. The gasoline economy comes from situations where the hybrid powertrain can shut off the gas engine and run on the electric motor alone.

The more you are at low throttle and low speed, the more you coast to a stop, the more you stop and gently go, the better the gas mileage. The less you are under these conditions, the less you use the electrical drive and the lower the gas mileage. This cannot be emphasized enough!


Published in Police Fleet Manager, Mar/Apr 2006

Rating : Not Yet Rated


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