The Fastest Way To Fuel Efficiency

The EPA and DOE have released the new Fuel Economy Guide for the coming model year. 2015 looks like a great year for fuel efficiency, with manufacturers offering a much-expanded selection of fuel-efficient models.

Unfortunately, the Guide does not include SUVs and passenger vans with a GVWR of more than 10,000 pounds, or other vehicles with a GVWR of more than 8,500 or a curb weight of over 6000 pounds. The reason is that the law does not require manufacturers to release fuel-efficiency information for these vehicles. The Guide is still an important resource for companies that maintain fleets of small vehicles, however.

The Guide makes it easy to determine which models have the best fuel economy for their class, which can use alternative fuels or flex-fuels, and which have new, more efficient technologies, such as start-stop systems.

However, upgrading fleet-wide fuel efficiency requires more than simply choosing the vehicles with the best fuel-economy rating or the latest efficient gadgetry. For one thing, the Guide rates each model within its class, so that even the top-rated vehicle in one class might be less efficient than the mid-range vehicles of another class. For another, how a vehicle is used has a big impact on how efficient it is. For example, small vehicles tend to be more efficient than larger ones, so a company might be tempted to buy under-sized cars and make up the difference in storage space with roof-racks. The problem is that a loaded roof-rack decreases fuel efficiency by 5%, according to the Guide.

When upgrading a fleet for fuel efficiency, it makes sense to consider right-sizing the fleet first. Switching to smaller models might ultimately lead to greater fuel savings than choosing the most efficient model of an unnecessarily large class. Conversely, a car that is too small, or otherwise not right for the job, can raise fuel consumption again.

Besides the fuel efficiency number itself, the Guide also provides information on various technologies that influence efficiency. Again, fleet managers need to consider the particular needs of their company before deciding whether to purchase a particular technology.

Hybrid engines, for example, are much more efficient than non-hybrids of a similar size that use the same fuel type, but hybrids are not always the best path to fuel efficiency. For example, the Ford Escape comes in a hybrid version that gets about 10 MPG better than its standard counterpart. That’s enough to bring its highway fuel economy into the mid 30’s, which is pretty good, for a light SUV. The Chevrolet Cruise 2.0L Diesel 6AT, on the other hand, gets 46 MPG and it isn’t a hybrid. It’s just small, lightweight, and a diesel.

The lowest MPGs on the road belong to electric vehicles and plug-in hybrids, since these derive at least part of their power from somewhere other than a gas tank. They are excellent options for companies that have ready access to affordable electricity from a non-fossil-fuel source, such as wind or landfill gas. But if the only electricity available was generated in a coal-fired power-plant, then plugging in a car increases its carbon footprint. Generally, alternative fuels and electric vehicles complicate fuel efficiency calculations because different energy sources have different environmental and monetary costs. For those willing to tackle that complexity, all the new options are definitely a good thing.

Choosing a vehicle with an eye towards greater fuel-efficiency is all about juggling context—the type of driving the company needs, size requirements, budgetary constraints, and different types of energy sources. But while the Fuel Economy Guide cannot deliver a simple, ready-made answer as to which vehicle to buy, it is a convenient and easy-to-use resource.