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Real MPG ratings

The EPA's laboratory fuel mileage tests were initiated more than 25 years ago to provide a means for consumers to make valid fuel-mileage comparisons between vehicles. Posting of mileage numbers on the window sticker is required by law. Auto industry practice has consistently been to use the EPA-provided numbers to assure a level playing field. However, many things have changed over the past 20 years - speed limits have increased, congestion has increased, and vehicles have more power-hungry accessory equipment, such as automatic climate control. The EPA tests are conducted in controlled laboratory conditions, at average speeds of no more than 48 mph, without air conditioning and at moderate temperatures. Test values are then adjusted down using adjustment factors developed by the EPA in the mid-80s. While this provides consistent comparison data, it is widely accepted that many drivers of all types of vehicles experience lower results than the labels. For example, during Autobytel testing, the Toyota Prius consistently logged a miles-per-gallon rating in the mid-to-upper-40s, and other hybrids, such as the Ford Escape Hybrid, rated real world in the mid-to-upper 20s. It's important to take the EPA ratings, realize that you will get less than what is reported, and factor your driving habits and most common routes.

Power vs. Economy

Automakers have discovered two primary benefits to hybrid technology: more power, with better efficiency, and total efficiency. Trouble is, they aren’t necessarily willing to broadcast the differences. Case in point: the Toyota Highlander Hybrid and the Honda Accord Hybrid. Curious shoppers may think that they’ll get great fuel mileage and low emissions with these vehicles, but they won’t – at least not what many assume they would get from a hybrid vehicle. The Highlander and the Accord are power hybrids, designed to offer excellent torque and performance by basically mating the electric part of the hybrid powertrain to V6 engines.

Other power hybrids include the recent batch of vehicles from Lexus, such as the 2006 Lexus RX 400h – a luxury SUV that gets about 26 miles to the gallon, and actually offers a more spirited drive than the more traditional RX. Also coming soon from Lexus is the world’s first rear-drive hybrid, the 2007 GS 450h – a powerful performance machine, not to be confused with, say, a Honda Insight.

The result of these power hybrids is great fun and improved efficiency, when compared to vehicles of similar performance character, but not when compared to hybrids that usually feature four-cylinder engines and continuously variable transmissions, such as the Toyota Prius, Ford Escape Hybrid or Honda Civic Hybrid. These are economy hybrids, and the focus here is what people generally think of when they think hybrid: high miles per gallon, low emissions, and, as a result, not-so-hot performance. Of these, however the Ford Escape Hybrid does not qualify for access into HOV lanes, because it generates less than 45 mpg – a ridiculous ruling, when you consider that even the gas-sipping Prius is lucky to get 45 in real-world driving.

Plug-in power?

Do hybrids need to be plugged in? There is no need to plug in hybrid vehicles. They have electric motors and gasoline engines which work together to provide power. The batteries for the electric motor are re-charged by energy captured as the driver brakes or coasts in the car and also by a separate engine-driven generator.

Why doesn't the Prius offer a plug-in option so it can run in electric-only mode? Great efforts went into making hybrid cars so they DON'T have to be plugged in. If a car is converted, it will have a negative effect on the life of the batteries and the reality is that it's likely the grid electricity being used is derived from coal, so there's not much, if any, savings to the environment. Additionally, the electric-only mode would be good for less than a mile at low speed, so the practicality of it is very limited.