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NREL Estimates US Hybrid Electric Vehicles Have Saved Nearly 5.5M Barrels of Fuel

Hybrid electric vehicles have saved close to 230 million gallons—5.5 million barrels— of fuel in the United States since their introduction in 1999, according to a recent analysis conducted by the US Department of Energy’s National Renewable Energy Laboratory (NREL).

To estimate the total fuel saved by hybrid electric vehicles, NREL researchers combined hybrid electric vehicle sales and fuel economy data to determine fuel savings. The fuel economy data included new EPA mpg ratings, and the researchers also reviewed old EPA mpg ratings and user-reported values.

NREL used the VISION modeling software developed by Argonne National Laboratory to determine vehicle stock—the total number of hybrid electric vehicles in use in a given year.  The annual vehicle stock estimates and the vehicle sales data were combined to calculate fuel savings of replacing a conventional vehicle with a hybrid.  The conventional vehicles selected were models by the same manufacturer that most closely matched the hybrid electric vehicles in terms of size, weight and performance.

Sales of hybrid electric vehicles have increased an average of 72 percent a year for the past five years and in 2006 the average fuel economy based on new EPA estimates was 35 miles per gallon for new hybrid models sold in the US.

—Kevin Bennion,  NREL

In 2006, the average fuel economy improvement for hybrid electric vehicles over the replaced conventional vehicle was approximately 45%.

Even with this improvement, hybrid electric vehicles would have to replace a significant portion of the total light duty vehicle fleet to have an impact on petroleum imports.  For example, net imports of oil in 2003 were 11.24 million barrels per day, and 8.55 million barrels per day went to light duty vehicle use.

Although the fuel savings from hybrid electric vehicles to date is relatively small compared to the total fuel use, as the technology matures and these numbers increase they can have a significant impact in reducing our overall transportation fuel use.

—Matthew Thornton, NREL Center for Transportation Technologies and Systems

The Center for Transportation Technologies and Systems has conducted research to advance hybrid electric vehicles viability in the marketplace since the early 1990s.  Today, the Center focuses on developing and evaluating new technologies such as hydrogen, biofuels and plug-in hybrid electric vehicles.


David Grenier

Even with this improvement, hybrid electric vehicles would have to replace a significant portion of the total light duty vehicle fleet to have an impact on petroleum imports.

While this is true, I think it assumes that one would replace a non-hybrid with a hibrid version of the same make/model. So for example I could trade in my Canyonero SUV that gets 8mpg for a Canyonero Hybrid that gets a whopping 11mph. But I think the explosion of awareness about global warming and the sustained high gas prices that are no longer seen as something that will just drop like they did in the 80s will lead to people replacing heavier vehicles with lighter ones as well as moving to hybrids and diesels. SO hopefully it won't mean going from a Honda Civic to a Honda Civic Hybrid, but going from a Honda Ridgeline to a Honda Civic Hybrid or a Dodge Durango to a Chevy Volt. Sure, there will still be folks out there who NEED a big truck or SUV for their job or because they have six kids... but I think a lot of folks who don't need an SUV are going to think long and hard next time they buy a new vehicle about whether a Prius or Diesel Passat will do.


David: I agree. People will make billions of tiny decisions that add up. It takes a while. The improved quality of vehicles actually delays this.

Fifty years ago a car might well be shot after a few years. But now they last. We got rid of: salt on roads, potholes, rustproofing, carburetor and ignition problems, automatic transmissions failing at 40K miles. And got better materials and fit on everything. Far less need for winter chains and lubrication and more garaging.

Every gallon of gasoline uses energy just to reach the filling station. When you buy less it saves fuel in a long string leading to the well.

Reality bites.


I agree with david.
Three years ago I was talking with my neighbor about trucks (he had 3 heavy duty trucks in his driveway at the time).He was looking at trading in the smallest one (an f-250) for something bigger, because he wasn't sure if this vehicle was big enough to meet his "needs".
Yesterday I talked with the same neighbor (now down to 2 trucks). He is shopping for a Used VW golf tdi to replace the F-350.
It turns out that his primary "need" for The f-350 was bragging rights about what he could tow, and how high up he sat. The golf tdi would give him bragging rights of getting close to 50 mpg without "one of those tin can japanese hybrids".
This weekend he is driving over 200 miles away to check one out.
This guy is a prime example of someone trading in a <10MPG vehicle for a >40MPG vehicle in a different class.


It takes a while. The improved quality of vehicles actually delays this.

No kidding. My next vehicle is probably going to be a diesel Jetta wagon, but my 2000 Maxima is in such great shape that I can't bear to trade it in. As soon as something major starts to go wrong I'll do it, but in the meantime it runs very nearly as well as it did new.


Interesting article. I find it hard to decide if it's encouraging or discouraging news that it's taken 8 years for hybrids collectively to have saved the energy equivalent of 1 day's domestic production. (Every day America processes a total of ~15-16 million barrels of oil; of this, ~5-6 million barrels are produced in the U.S. and thus are not imported). See Staggering how much oil that is.

Not that it matters much overall given those huge numbers, but from what I can tell about the study's methodology, the study's conclusions are probably too conservative. Owners seem to adore their hybrid vehicles, and I suspect that, as more Americans buy them, they will become the car of choice for families, particularly if gas prices rise. So, it's not just that hybrids are replacing existing gas-guzzlers on the road (what the study seems to have measured); it's that families are increasingly choosing them instead of their other vehicles. This would presumably result it additional fuel savings not captured by the study.


A study by UC Davis and AAA seems to reinforce the idea that people do not trade in a car from the same class when purchasing a hybrid. Rather, they replace a less efficient vehicle with the the more efficient HEV. If this is indeed the case, then potential fuel savings may be much more significant.

For example, at the current rate of HEV adoption, the study estimates a savings of 0.4% of total oil use. (Equal to 498 million gallons of gas per year, or about about 10 large tanker ships.)

Here's the study:


It just so happens that I happen to be one of those people who went from a 12mpg old corvette and a 18mpg jeep to a 07 Prius avg 48mpg and what a difference it has made. Of course I still bring the vette out on occasion for a night on the town and the jeep still gets some use for off roading or hauling things. But since purchasing the Prius 4 months ago each other car has been used maybe once or twice a month. The primary being the Prius and the difference in fuel economy made economic sence. With what I was spending in gas to what I do now, the cost of having the prius vs the savings in fule ment I could drive a brand new car for an extra $75 a month.

Speaking of little decisions many friends have asked me to give rides as I do have the cheapest car to drive. I oblige as this also reduces gas consumption over someone else doing it in a gas guzzeler.

Of course there is still the need to haul things on occasion. But thank goodness we will have a bunch of SUVs and big trucks that were everyday drivers sitting around only getting used when needed. For example my parents have a farm. For this and for hauling horses and hay and other working farm related things a V10 Dully monstrosity is used...but only for work type jobs. Occasionally I barrow it, but as I did yesterday and topping it off the other day and having to spend $75 to fill it up was a harsh reminder how how painful it can be at the pump, Driving a prius spoils one as gas is needed only every 500 miles or so and filling up is usually about $30 In the long run economics will win no matter what.
People will over time trade in for more efficient cars but still keep the monstrosities in the mean time and will make the appropriate decision's for use for whats appropriate. Including walking or biking!


I agree with most of these comments. We can generally assume that the rate of adoption (curve) for alt fuel vehicles will increase as product offerings grow and externals like climate and oil pricing remain.

What is clear is that a corner of sorts has been turned. Consumers are aware of the economics, the environment, the security issues. There's one other idea that's gaining purchase in the decision process - the benefit of doing something good for someone else.

Who would have thought it?


"Japanese hybrid Tin can?" You can't fault those drivers who buy them. It's the only game in town. Otherwise it seem that everone is in agreement; more fuel effecient cars are the way to go.
I'm waiting for the '08 Camry hybrid "tin can." Meanwhile, I've cut the miles traveled on my '93 Ford Ranger by about 40%.


The LA Times ran an article about Plug-in hybrids awhile back titled "The 500 MPG Solution". In your dreams, diesel burners! Only a diesel engine paired in a plug-in hybrid drivetrain can achieve that fuel economy. Combustion of any fuel in a plug-in hybrid engine is perfected through strict regulation of engine speed and load.

But of course, such mileage is only possible if daily miles driven are kept low (20 miles or so), on batteries alone. Perfect! When trips are short, more become accessable without having to drive.

Battery operation is likely to remain less expensive than any fuel. Add rooftop photovoltiac panels as a means to charge them, and a household gains an emergency backup power supply, invaluble in an emergency or utility grid failure. There's no way to top that, TDI fans.

Did I forget to mention that mounting the plug-in hybrid batteries low on the frame, lowers vehicle center-of-gravity and improves stability and handling, a important safety factor for top-heavy SUVs. Is a 500MPG Ford Expedition possible? Probably, but they'll be driven even less daily. Fine with me.


Only one day of oil saved? That will change dramatically
as HEVs become obsolete and PHEVs rule the day. Then you'll see some real impact.

Kip Munro

The number of hybrids on the road is going up exponentially. In 1999 only a handfull of Insights were sold. That first year only a few hundred barrels were saved. Last year almost half of the total savings were achieved. That's what 75% increase per year means. Next year alone 4.1 million barrels will be saved if the past rate of increase continues! Recent data indicates that the rate of increase is also increasing. Couple this with the knowledge that hybrids will stay in service longer that other vehicles currently being sold to understand the bigger picture.

Gerald Shields

This info from NREL is stating the obvious: Hybrids keep you from going to 7-11 to fill up! However, I also agree with some of the comments posted. Given this though, hybrid are here to stay and the more fuel-efficient that hybrid is, the better. Moreover, I don't buy into the Big Three's assertions about having to give up size and safety for fuel-efficiency and even if you give up size, you won't need to give up safety. Take the Smart Car. It's small, but it's built like a walnut.

Greg Goede

I own a Ford Escape Hybrid and love it. I think the gas only model gets 16 MPG according to a friend who has one. I get about 32 MPG. I maintain a spreadsheet on it and I can honestly say that I do use a lot less gasoline.

Hybrid tech will slowly become integrated with all vehicles regardless of the source of power. So, electric, hydrogen, methane, diesel will all benefit from regenerative braking.

My next update will have me installing a kit to turn my vehicle into a PHEV. I'll do that when I see a kit get to maybe $3,000. It will be nice o charge up and get an effective MPG of 60+.


We'd have saved a lot more fuel had we decent diesel choices here in the U.S.

50-state approved VW diesels will be back in a year, then the Asian diesels come a year after that (50 mpg highway Accord!)

The best of all worlds would be a diesel-electric car (parallel or series hybrid), but we're so addicted to gassers over here I doubt it will happen.

I'm waitinga couple of years for my next auto purchase - and it will absolutely have a diesel prime mover.

Red Badger

....automatic transmissions failing at 40K miles.

Apparently, you've not owned a recent Chrysler product......

I find it hard to decide if it's encouraging or discouraging news that it's taken 8 years for hybrids collectively to have saved the energy equivalent of 1 day's domestic production.

If the Republicans hadn't stalled the CAFE level at 27.5mpg for the last 22 years, there wouldn't be a problem.

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