My wife and I needed a new car. Like most Americans we wanted a strong value and gas mileage was a part of that equation. Also like most Americans I originally thought a hybrid car would be a good choice for us. Hybrids have grown in popularity over the years and now we even have pure electric cars and extended range gas/electric cars like the Volt and plug in Prius.

We also wanted a safe car and a car that I could transport my equipment in for most jobs so it needed to have a large trunk and cargo space. I have a home office but also make longer commutes a couple times a week on average for work. If I couldn’t fit the equipment I need for most of the jobs that required the commuting then having the extra fuel economy would be futile as I would need to take our Rav 4 anyway.

The Volt is an interesting car and heavily subsidized with some great lease options. I researched the real world range and mileage numbers. In a best case scenario the Volt will go only 50 miles on a full charge before the gas motor begins to run. In some cases you can’t even go 25 miles before the engine starts. The car is also on the small side and even after subsidies and tax credits over 30K. If I had a predictable commute under 40 miles and the ability to charge the car whilst it was parked it might have been a good choice. I am dubious of the size for my current average cargo load while working and the technology is new and a bit unpredictable.

Hybrids have come down in price but they are still costly. The technology is new and the batteries are very costly to replace. The EPA numbers on fuel economy also tend to be higher than real world driving for most. For many drivers the cost benefit doesn’t add up even at $4-$5 a gallon for gas. With all this in mind we ruled out the hybrids available including the Prius, Volt, Fusion, Camry, Optima and Lincoln MKZ.

I had read that the VW Passat was the Car and Driver car of the year last year and decided to consider my first VW Diesel. Diesel engines work differently and are much more efficient than gas. The Passat gets 30 MPG city and 43 Highway according to the EPA numbers. When I looked into real world mileage the results were even better. Edmunds crowned it the winner of their 40MPG challenge:

“The diesel-fueled Passat TDI’s win was characterized by editors as a “true shocker,” given that it was by far the largest, heaviest car in the test. It averaged 43 mpg even in city driving and an amazing 51.7 mpg on the Interstate highway portion of the test route.” – Edmunds

A couple who specialize in fuel economy broke a Guiness record for miles on one tank of gas using a TDI Passat:

Over the three days the couple traveled 1,626.1 miles on a single tank of ultra-low sulfur diesel fuel. Averaging 84.1 mpg, the couple tried to drive in typical driving conditions.

They included 120 pounds of luggage and drove during the day time so they would possibly run into rush hour traffic in the morning and afternoon. They also never drove more than 14 hours in one day. – The Car Connection

On top of the stellar fuel economy the Passat is a large car with 15.9 cubic feet of trunk space and ample leg room in the back seat. With the seats folded down and the driver seat set for my 6′ frame the car has 6′ 9″ of linear space from trunk to drivers seat. I was shocked when I realized that the Passat was longer than our Rav 4.

Needless to say we purchased a 2013 Passat SE TDI (Turbo Direct Injection Diesel) with automatic transmission and navigation. So far I have logged about 250 miles on the car with about 70% highway and 30% city driving. The car is quiet, comfortable and spacious. It accelerates nicely with its’ strong diesel torque and passing on the freeway is easily accomplished. This is my first car with an onboard trip computer that gives constant mileage feedback and I find myself driving much more conservatively than before. I haven’t been a lead foot driver anyway but I find myself accelerating slower and allowing more room on the freeway for less stopping and going overall. I also have been minding AC use and turning off the compressor when accelerating. Overall I have been driving slower also rarely exceeding 70 miles per hour on the freeway.

On my first long commute, 75 miles one way I managed to get 53.9 miles to the gallon. I drove about 80% on the freeway with 15-20% of that being in moderate to heavy traffic. I was driving conservatively and ran the AC very little. On mixed in town and freeway shorter trips I have managed 38-51 MPG depending on how conservatively I drive and a bit of luck with traffic lights.

Today I decided I would drive normally when picking up my son at school. It is a 25 mile round trip route. I made a stop at the grocery store as well and overall drove about 15 highway miles and 10 city miles. I ran the AC and accelerated briskly a few times. I got 39 miles to the gallon for the trip.

Some mechanics and owners claim that diesel engines improve economy with time. In the aggregate diesel engines last longer than their gas counterparts. VW engines are slightly more costly to repair than an average Toyota or Ford/GM but overall costs of ownerships are very similar. JD Power did give the Passat only an average rating on durability over time. Time will tell with our experience, many owners report excellent lifespans with their TDI Jettas which have been around longer than the Passat.

Diesels are very common in Europe but not in the US. Diesels used to produce much more smog causing particulate matter. New diesel engines use special technology to eliminate most of the particulate. Another big change has been ultra-low sulfur diesel fuel now easily purchased in all 50 states. VW TDI’s had low enough emissions to qualify for the lean burn technology tax credit offered by the IRS. New VW TDI’s can be coverted to biodiesel and can use a B5 blend which has 5% biodiesel without voiding the warranty.  I am not a believer in biodiesel anyway but for those that are they can convert their cars. Diesels are also no longer hard to start in cold weather thanks to direct injection and more advanced computerized engines.

Mercedes, BMW, VW and Audi all offer a range of turbo diesel cars and SUV’s. My Passat was about $3500 more than a comparable gas model, a premium of 12%, some of the luxury cars are only 2-3% more for diesel models. You will have to do your own math given the miles driven to decide if the premium is worth the savings over time. For many people neither diesel or hybrids make sense economically if they don’t drive very much and do not keep their cars for more than 3-5 years. Diesel TDI’s from VW appear to be in strong demand and we had trouble even finding used ones. The used cars we did see (Jetta’s) held their value very well.

It might be obvious to many of you: why not combine diesel with hybrid technology? I do not know of any engineering reason why this can’t happen. My suspicion is that the price point would be too high for many consumers and auto manufacturers haven’t done it for that reason. Diesel and hybrid tech both add cost and so combining them would add significantly to the sticker price. The Volt is a good example of a car that seems to have suffered over too high a sticker price.

What about all electric vehicles? Gas and diesel create so much more energy than lithium ion batteries can hold. I think the key will be battery tech, as batteries get more reliable, denser and cheaper the EV will become more and more attractive, especially for urban commuters in green states like California. Of the current available cars the Tesla S is the strongest for me. Unfortunately the range is still quite limited and does not represent real world driving either. EV vehicles are new technology and there will be problems, EV maker Fisker Karma has had all kinds of problems including fires and Consumer Reports broke their car before even road testing could begin. Worst of all EV makers including Tesla and Fisker have relied heavily on government loans and tax credit to bring their cars to market. If these cars are to be really viable they will have to stand on their own in the free market. For those that are environmentally inclined and think that CO2 is a big problem, all these vehicles are merely remote emission producers unless you have nuclear solar or wind power generation. (Of course emissions are also involved in production and disposal.) The Volt looks great on paper (for some drivers) but drivers aren’t buying it and it is costing GM a small fortune. Early adopters with deep pockets may find benefit in EV’s and hopefully the market will allow a truly worthy EV to emerge in the near future.

Driving Tips:

While I am not an expert I have been reading and focusing recently on fuel economy driving. Having the instant feedback from the car trip computer (not a perfect measure but a good reference) also helps tremendously. Here are my tips:

1. Drive more conservatively, don’t accelerate quickly, leave lots of room and drive at the speed limit or even a little under to get optimal fuel economy.

2. Braking is the enemy of fuel economy, it takes much more energy to get to speed than it does to maintain speed. Leaving lots of room where possible allows time for the car to slow without braking. I also stop accelerating when I see a stop light turn red ahead. Obviously you have to stop, but it might surprise you to see how often you can allow the car to slow without breaking and maximize your momentum just by being conscious of it.

3. Tires & Weight: Keep your tires a little north of the recommended range, (not more than 10% as it is dangerous to go higher) and take unnecessary weight out of the car. Items not needed can add up in weight quickly.

4. AC: Turn off the AC compressor when accelerating and on hills. The compressor is the AC part of your system not the fan. It is especially taxing on your car when the car is accelerating or going up hill. Just make it a practice to hit the AC button off when accelerating.

5. Shut off the engine: Next time you are waiting in the drive through or for your kid at school shut off the engine. Your radio should play on the battery for at least an hour or two without any problem. I have read that you should shut off your engine if you plan to idle more than one minute and that seems pretty reasonable.

6. Drive Less: This is obvious but bears repeating, combine trips, carpool where possible, telecommute.