Buying a more fuel efficient car

In my previous post, I compared the fuel economy of different types of cars in light of the news of the Ford Motor Company replacing their fuel-efficient cars for less efficient SUV's at a time when the price of gas is escalating. One of my readers pointed out that the Hyundai Tucson and Hyundai Elantra are built on the same platform, and have the same engines, and wondered how they compared. I like to use the real world fuel economy reported at fuelly.com, as these numbers are going to be more reflective of what people are getting day to day as opposed to what's calculated in some lab. As it turns out, the Elantra gets noticeably better fuel economy than the Tucson, which might have some people scratching their heads. That's when I realized, this is a perfect opportunity to look into what matters when it comes to fuel economy, as the Tucson and Elantra might seem like they should both get very similar fuel economy. So let's do the research, dig into some history, and figure out how to buy a more fuel efficient and safe car in a country where gas is set to go past $1.50 per liter.

Real World vs. the lab

If you were to look at the Hyundai Elantra and the Tucson from below, you might have a difficult time telling them apart, as they are literally built on the exact same platform. Car manufacturers have been doing this for a long time; one of the most notable was Chrysler in the 1980's, building everything from a compact car to a minivan to a luxury sedan on the K car platform. As remarkable as this seems, it makes sense that a frugal car company should try to get as much diversity from a platform as possible so as to offer a greater variety of cars for a better price. Both the Elantra and Tucson are IIHS top safety picks, so it's pretty clear that safety was not compromised in this cost-savings move. 

If we look at Hyundai's own numbers, the Tucson is reported as delivering 10.1L/100km in the city, 7.8L/100km on the highway, and 9.0L/100km combined. The Elantra is reported as delivering 9.3L/100km in the city, 6.4L/100km on the highway, and 8L/100km combined. When we go to fuelly.com, we find out that, when looking at the 2017 model (as the 2017 model year offers us greater data points), the 2L Elantra is delivering an impressive 7.27L/100km combined, while the 2017 2L Tucson is averaging 9.87L/100km. This tells us that the Elantra's economy is being understated, while the Tucson's economy is being overstated. One of the reasons why this could be is that the Elantra starts at $15,999, while the Tucson starts at $24,999, nearly $9,000 more, indicating that the profit margins are significantly better on the SUV than on the sedan, so Hyundai sales executives, knowing the Elantra will sell on price alone, are going to want these two vehicles to appear to have similar fuel economy so that they can push the more profitable Tucson.

I've heard many people, including those on the evening news who claim to be on your side, praise the fuel economy of modern SUV's, but in actual fact, all else being equal cars nearly always do better, and the main reasons are aerodynamics and weight.

Aerodynamics

The history of automobile aerodynamics dates back to before the turn of the 1900's, and has been refined to a perfect science throughout the last century. The result was sleek, rounded coupes and sedans. This video by VOX demonstrates the value of aerodynamics when it comes to fuel economy over the last century:

Now, it's pretty obvious that the Hyundai Tucson is pretty rounded for an SUV, and is definitely more aerodynamic than a regular truck. However, it's not nearly as aerodynamic as the Elantra. One reason is because it's taller, and the other reason is because it sits higher off the ground. A taller vehicle has to deflect more wind than a lower vehicle, and one that sits higher generates more turbulence beneath the car caused by tires (which are not aerodynamic) and components like the exhaust system. Auto makers contend with this by installing a front chin wind deflector, which is that black piece of plastic under the front bumper that always seems to get caught on curbs. An SUV sits higher up, so you probably won't scrape the front chin wind deflector on any curbs, but that still does sacrifice a bit of fuel economy. This is one of the reason why many crossover vehicles tend to have less ground clearance today, but generally still more than a sedan.

An easy way to tell how aerodynamic a new car is going to be is to look for the drag coefficient number in the specifications. You don't need to understand how this number is calculated, all you need to know about it is that the lower this number, the more fuel efficient it will be. Any number under 0.3 is going to be decent. If this number is missing from the advertising literature, it's probably because the vehicle isn't very aerodynamic. When it comes to the Elantra, Hyundai proudly proclaims that it has a drag coefficient of 0.27, which is very good. The Tucson's drag coefficient was more difficult to find, but I did manage to find it, and it's at 0.33, which is significantly worse than the Elantra, but still better than some other SUV's and even some older cars on the road.

Weight

Another factor that helps to determine the fuel economy of a vehicle is it's overall weight. In the case of the Elantra, it has a reported curb weight of around 1,255 kilograms, while the Tucson is reported as having a curb weight of 1,508 kilograms. That 253 kilogram difference is going to have a negative impact on fuel economy as well. SUV's and crossovers will generally weigh more than their sedan counterparts, because they are taller and therefore require more metal to create the taller structure. They also need larger, heavier components to give them greater ground clearance (shocks, struts). A sedan design makes more efficient use of the metal that the vehicle is made out of, which is why it will be lighter.

Trade-offs

When you buy an SUV like the Tucson over a sedan like the Elantra, you are obviously trading off fuel economy for greater ground clearance and a more upright seating position. These can be important considerations if your mobility is impaired or you frequently drive in places where the road conditions are poor. However, you are also trading off the fact that a sedan does handle corners a lot better due to a lower center of gravity, and provides better performance when accelerating due to lower weight and better aerodynamics. There is also the fact that a trunk in a sedan offers greater security of items stored within than does the hatch of the SUV; a would-be thief only needs to smash the back window to clean out the back of the Tucson, while breaking into the trunk of an Elantra will require a lot more work.

At this point, I think we should plug some numbers into our spreadsheet to find out how much more the SUV is going to cost us in five and ten years with gas at $1.50 a liter:

Model	MSRP	L/100km	30k/year
Elantra	$15,999.00	7.27	$3,271.50
Tucson	$24,999.00	9.87	$4,441.50
	5 years	10 years
Elantra	$32,356.50	$48,714.00
Tucson	$47,206.50	$69,414.00

What is interesting is that this demonstrates that we can buy and drive a base model Elantra for 10 years for nearly the same cost as buying and driving a base model Tucson for 5 years. Also, the savings of driving an Elantra over 5 years is just a tad over $1,000 shy of buying another new base model Elantra. 

Other considerations

There are other things to consider when buying a new car; this blog post doesn't take into consideration predicted reliability, cost of maintenance, and insurance costs, which are all factors one should also consider when buying a new car, truck, or SUV. Insurance costs on a sedan may be better than they are on an SUV, simply because the replacement value is lower. I would expect the maintenance costs to be similar on these two vehicles, except that some SUV's require truck tires which tend to cost more than car tires. A quick look at Canadian Tire's site shows this to be true; new tires on the Tucson are going to cost more than will new tires for the Elantra, further proving the sedan to be the frugal choice.

Conclusion

While SUV's and CUV's are the hottest trends in the market today, it's important to remember that being frugal means ignoring the trends salespeople are trying to push on us and to make calculated, intelligent decisions for ourselves. SUV's and crossovers are an excellent choice for some people depending on their needs and lifestyle, and may represent a more frugal option compared to buying a full out SUV or truck, but at the end of the day, the modern sedan is hard to beat for economy, safety, and overall value.