What is MPGe?

Greater environmental protection measures have led to a pushfor more fuel efficient vehicles. Along with the development of catalyticconverters, air fuel ratio sensors,and O2 sensorsfor standard gasoline engines, automakers have looked for alternative ways to fuel our transportation needs. Most popular today are gasoline-electric hybrids, butmore recently, fully electric vehicles have been in the spotlight as the mostgreen and efficient option available today.

 One challenge for the EPA was how to relate the fuel efficiencyof fully electric vehicles to consumers. We are all used to the standard MPG –or miles per gallon – rating to compare the fuel efficiency of gasoline poweredvehicles, so the solution has been to provide a MPGe, or miles ger gallonequivalent, rating for all electric and hybrid vehicles.

The MPGe metric was introduced in November 2010 by the EPAto label the fuel efficiency of the new Nissan Leaf and Chevrolet Volt electriccars. The ratings are based on the EPA’s formula, in which 33.7 kilowatt hoursof electricity is equivalent to one gallon of gasoline. This is based on theenergy content of gasoline: burning one US gallon of gasoline is 115,000 BTU.The formula for calculating MPGe is shown below.

Two things must be taken into consideration for MPGe of electric vehicles: one  is the energy consumed to generate the electricity necessarycharge the battery; and the other is the transmission efficiency of that electricity from itssource into the battery. This makes the calculations much more difficult, butit is essential for getting an accurate depiction of the fuel efficiency ofelectric vehicles.

2012 Ford Focus Electric

 Even with all those factors taken into consideration, newall electric vehicles have impressive fuel efficiency. The 2012 Ford FocusElectric gets 105 MPGe and has a range of 76 miles. Certainly not capable ofroad trips, but it will get most people to work and back, and perhaps a trip tothe grocery store, with some charge to spare. This satisfies what most peopledo with their cars on a daily basis, and can save a good amount of money in thelong run on gas.

Does MPGe make sense to you?

The 2011 Lincoln MKZ Hybrid

The MKZ is built on the same platform as the Ford Fusion and late Mercury Milan, and the Hybrid can be seen as a further upscale replacement for the Mercury Milan Hybrid. The regular MKZ's 3.5-liter V6 is replaced with a 156-hp, 2.5-liter Atkinson-cycle four-cylinder gasoline engine and a 40-hp electric traction motor running power to the front wheels via a CVT transmission. It's a full hybrid, the second generation of Ford's system, and capable of operating seamlessly in gasoline, electric, or combined modes. EPA mileage is 41 city, 36 highway, and with a 0-60 time around 8.5 seconds, acceleration for merging won't be a problem. Lincoln offers a new alternative for the luxury hybrid buyer in its MKZ Hybrid.


SPECIFICATIONS

2011 Lincoln MKZ Hybrid

Base Price $ 34,330 Price As Tested $ 41,370 Engine Type full gasoline-electric hybrid Engine Size 2.5 liters / 152 cu. in. Horsepower 156 @ 6000 rpm Torque (lb-ft) 136 @ 2250 rpm Transmission CVT Electric Motor 40 hp permanent magnet AC synchronous (torque n/a) Maximum combined horsepower 191 Wheelbase / Length 107.4 in. / 189.8 in. Curb Weight est 3800 lbs. Pounds Per Horsepower 19.9 Fuel Capacity 17.5 gal. Fuel Requirement 87 octane unleaded regular gasoline Tires P225/50R17 93V Michelin XSE Energy Brakes, front/rear vented disc / solid disc, ABS, AdvanceTrac®, and regenerative braking standard Suspension, front/rear independent short-and-long arm / independent multilink Drivetrain transverse front engine and motor, front-wheel drive.RFORMANCE EPA Fuel Economy - miles per gallon city / highway / observed 41 / 36 / 35 0 to 60 mph 8.5 sec.

Hyundai Nuvis Concept

The Hyundai Nuvis concept (hybrid drivetrain) is destined for the next-generation Sonata...

As a parallel hybrid, the Nuvis can be driven in all-electric mode, gasoline-engine-only mode as well as any combination thereof. Engine management software automatically shuts off the gasoline engine when the Nuvis comes to a stop, improving overall fuel mileage and providing zero emissions, while Hyundai's Integrated Starter Generator (ISG) restarts the engine once pressure is applied to the accelerator pedal.

The Nuvis is notable for two reasons: First, its hybrid drive train will find its way into the next-generation Hyundai Sonata, and second, Hyundai says the concept's styling hints at what the Santa Fe's replacement could look like.

Hyundai's Hybrid Blue Drive architecture combines a 2.4-liter 4-cylinder (known as the Theta II) with a 30- kW electric motor, the last also producing 151 lb.-ft. of torque. The total estimated output of 228 bhp is put to the road via a 6-speed automatic transmission. Hyundai says the Nuvis's lithium polymer batteries, which are stored underneath the trunk floor, are more durable and space efficient than nickel-metal hydride and lithium- ion versions.

Detailed stories at Hyundai Nuvis Concept

The Kia Forte LPI Hybrid

Kia Forte LPI hybrid car, powered by hybrid power train that consist of a 114 hp 1.6 liters LPI (Liquefied Petroleum Injected) engine and 20 hp electric motor. The company claims their new hybrid achieves fuel economy of 17.2 kilometers per liter of LPG fuel (41 MPG US), the equivalent to 21.5 kilometers per liter of gasoline. The electric motor is powered by highly advanced lithium polymer (Li–poly) battery that is new lighter and smaller battery with higher output than nickel-metal hydride batteries.