Hybrid electric
Starting in 2007, MGE began testing commercially available hybrid electric vehicles for various fleet operations.  We currently use Ford Escape hybrids for meter reading and other light-duty functions. We are exploring replacement options for our heavier-duty trucks.

Plug-in hybrid electric
MGE purchased a standard Toyota Prius hybrid and hired A123 Hymotion to add another, larger battery—one that is charged with grid power via an electric cord plugged into a standard 120-volt outlet. If widely adopted, plug-in hybrid electric vehicles (PHEV) using electricity from the utility grid could dramatically impact our future.

See also: MGE electric vehicle charging research

How hybrid electric vehicles work
A hybrid vehicle uses two or more power sources to propel the vehicle. A standard Prius hybrid electric vehicle (HEV) is powered by a gasoline engine and an electric motor. The electricity powering the motor comes from an onboard battery. The battery is charged by the engine and by vehicle braking and deceleration. The vehicle can operate in all-electric or all-gasoline mode, or it can operate on both simultaneously.  Standard hybrids are estimated to achieve about 45 mpg.

How plug-in hybrid electric vehicles work
MGE's modified Prius uses electricity generated by power plants to charge a second, bigger battery to power the car. The vehicle draws electricity from the new grid-powered battery first. When this battery is depleted, the original Prius battery kicks in to provide power as originally designed by Toyota. When driven at lower speeds, 34 mph or less, this PHEV can travel as far as 30 miles on a single charge without using gasoline.  Overall, this car may be able to achieve over 100 mpg.

PHEV performance
We have installed a fully automated monitoring device in our plug-in hybrid that monitors such things as:

• Fuel efficiency.
• Electricity use.
• Engine function.
• GPS data.

It communicates directly with the Idaho National Laboratory, which is operated for the Department of Energy (DOE) by Battelle Energy Alliance. We receive monthly reports from the DOE about our vehicle performance as it is driven by various people in various conditions. Following are their reports:

April 2010 [PDF - 293 KB]
March 2010 [PDF - 235 KB]
February 2010 [PDF - 287 KB]
January 2010 [PDF - 276 KB]
December 2009 [PDF - 239 KB]
November 2009 [PDF - 306 KB]
October 2009 [PDF - 311 KB]
September 2009 [PDF - 525 KB]
August 2009 [PDF - 460 KB]
July 2009 [PDF - 458 KB]
June 2009 [PDF - 522 KB]
May 2009 [PDF - 446 KB]
April 2009 [PDF - 443 KB]
March 2009 [PDF - 456 KB]
February 2009 [PDF - 518 KB]
January 2009 [PDF - 286 KB]
December 2008 [PDF - 294 KB]
November 2008 [PDF - 296 KB]
October 2008 [PDF - 448 KB]
September 2008 [PDF - 446 KB]
August 2008 [PDF - 443 KB]
July 2008 [PDF - 440 KB]

Historical hybrid use
We have a 30-year history of testing alternative-fueled vehicles in our fleet. Most have been hybrids, that is, duel-fueled vehicles.  We have used:

• Electric
• Beginning in 1975
• Battery fire in 1978 ended the project
• Liquid Propane
• Beginning in 1978
• 60 vehicles at peak use
• Switched to all CNG in 1988
• Compressed Natural Gas
• Beginning in 1986 through today
• 50 vehicles at peak use
• CNG vehicles no longer readily available
• Biodiesel
• Beginning in 1999
• Switched to ultra-low sulfur biodiesel in 2006

For more information
Hybrid Electric Vehicles: Exploring New Technology [PDF]
Hybrid Vehicles at MGE [PDF]
U.S. DOE Electric Vehicle Information