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Published on March 12th, 2019 | by Jennifer Sensiba

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Waiting For The Model Y Or Another Future EV? There Are Things You Can Do Now To Reduce Driving Impacts & Costs

March 12th, 2019 by  


With the upcoming announcement of the Tesla Model Y, and with better and better electric vehicles (EVs) coming out every year, many of our readers might be waiting to switch to an electric ride. Many are waiting for lower prices, more charging stations, more range, or simply want a form factor that isn’t yet available, like a pickup truck or off-road SUV.

Whatever your reason is, there are still things you can start doing today to reduce your car’s impact on both your wallet and the environment. Plus, if you get in the habit of driving efficiently now, you’ll get a lot more out of your EV when you make the switch!

Take Care of Your Car

The most important thing you can do to reduce fuel consumption and pollution is to keep the vehicle in good running order. A broken part, low tires, and overly worn parts can all cost you serious money at the pump. While everything can’t be covered in this article, there are a few basics you need to consider

Read The Flipping Manual

If you haven’t already, look at your vehicle’s manual and, if you’re a DIYer, read a shop manual. It will give you a good idea of what the car needs and how often. When oil isn’t changed, filters get dirty, or things get too worn out, they usually start to cost you extra gas before they make noise or leave you stranded. By staying ahead of the maintenance, you don’t take the hit to fuel efficiency.

Tires Matter, a LOT

Tires are, quite literally, where the rubber meets the road. When the pressure gets low, it’s harder for your car to push itself down the road, and the car will use more fuel. Always air the tires up to at least the pressures recommended in the manual or inside the driver’s door. If you’re willing to put up with a little more road noise and a slightly harsher ride, you can air the tire up a few pounds higher to save fuel, but don’t go overboard. Too much pressure can increase the chance of a blowout.

Don’t Ignore Noises and “Check Engine” Lights

If your car starts to make any strange noises, acts strangely at all, or gives you the dreaded “check engine” light, don’t ignore it. Consult a mechanic, do some internet searches, or read a shop manual. If you get the warning light, most auto parts stores provide free scans to see what is causing the problem. Fix it up ASAP before it starts costing you and before emissions increase.

Keep an Eye on Your MPG

The “Old School” Approach

The simplest way to see how many miles per gallon you’re getting is to track your miles, track your gallons, and divide the miles by the gallons. People have been doing it this way for a long time, and a drop in efficiency was often a sign that the car needed a tuneup or other work to get efficiency back up. Just use your car’s odometer or trip odometer to see how many miles you drive between one fill-up and the next. If you fill the car until the pump first “clicks” off, and then do the same next time, you can check the pump’s display to see how many gallons you put in.

The biggest disadvantage to this approach is that you don’t get a detailed picture of your car’s efficiency. You only know how well you did and how the car did during the whole time between fill-ups.

Real-Time MPG Tracking

Most newer cars have a built-in MPG display, somewhere in the dash. By using either a steering wheel control, a button on the dash, or controls in the center console, you can access it. For detailed instructions, see your car’s manual. For some cars, you can also find YouTube videos explaining how to find it.

Hopefully, it will give you two important numbers: current MPG and average MPG. Current MPG tells you what kind of mileage you are getting right now. Going down a hill, this number may be in the hundreds, but going up a hill, the number might be very low, like 1–5 MPG. To see what your car does over several miles, you’ll need to watch the average MPG. The average can be reset, usually with a long-press of the OK or select button.

By keeping an eye on these numbers, you can see how your driving affects your gas mileage and learn over time how to use less fuel. The higher you get your MPG to go, the less you’ll create harmful emissions.

If your car doesn’t give this information on a dash display, but is a 1996 or newer model, you can use the OBD II port to get this information. One cheaper option is to use a bluetooth OBD adapter and a smartphone app like Torque Pro. If you want an option that requires less setup each time you drive, you might consider the ScanGauge II computer.

For older vehicles, your options are more limited. For vehicles with fuel injection that are older than a 1996, you might be able to install an MPGuino computer or have somebody with the skills to do so install one. For most older vehicles, the only option to see how efficient your car is from moment to moment would be to use a vacuum gauge (more details here).

Drive More Efficiently

The above chart, produced by the U.S. Department of Energy, shows where the energy from a car’s gasoline goes. The top part shows how it breaks down for city driving, while the bottom shows highway driving. You’ll notice that it starts with 100% of the possible energy that could come from the fuel.

The Engine

Right away, it takes a big hit at the engine. Anywhere from 75–81% of the energy is lost, on average. Diesel engines are a little better, but still lose the vast majority of the fuel’s energy. The problem here is waste heat. Most of the energy leaves the engine as heat through the radiator, the sides of the engine, and out the exhaust system. This heat drifts off into the atmosphere and is forever lost to any useful purpose. Only a small fraction (19–25% on average) of the fuel is converted to mechanical energy that moves the vehicle.

While automakers have made great progress on improving the efficiency of gas and diesel engines, the laws of physics are still in effect. About the only thing you can do to keep the engine from making waste heat is to shut it off. Hybrids, the most efficient gas vehicles, run the engine as little as possible, and that helps save fuel. Ultimately, though, manufacturers are going to need to switch to electric vehicles to stop the waste.

To save fuel on a non-hybrid car, try to shut the engine off as much as possible. For any stop lasting longer than about 10 seconds, shut it off. For vehicles with a “stop-start” system, keep that system on and let it shut the engine off.

The other thing you can do is coast as much as possible with the transmission in gear (not neutral). For fuel-injected cars (most everything sold since the mid-1980s), the engine computer cuts fuel to the engine when you take your foot off the gas pedal. When this happens, you’re temporarily getting almost infinite MPG. The longer you coast when approaching a stop, the more you save.

One other thing you can do to save fuel is use engine accessories, like the alternator and air conditioning, less. High-powered stereo systems, battery chargers for tools, and doing anything else that draws a lot of power ultimately makes the engine work harder and uses some gas. While air conditioning is a life or death choice in hotter climates, you’d be surprised how often you can set climate control to vent only, without running the A/C, to keep the car comfortable.

Drivetrain

Drivetrain losses are mostly from friction inside the transmission and differential. There’s not a lot you can do here to help once you’ve bought a car, but if you buy another gas or diesel car, keep in mind that automatic transmissions have the most losses. Other designs, like manual transmissions and dual-clutch transmissions, waste less fuel.

If you do have an automatic transmission, try to minimize stops and starts as much as possible by picking highway routes, or driving on streets with fewer lights when possible. Also, if your transmission has a “sport mode,” “S” mode, “tiptronic,” “manumatic,” or “+/-” mode, the automatic transmission tries to act more like a manual and wastes less energy. Use those modes as much as possible.

Other Losses

After power gets to the wheels, there are three main things that eat up the rest of your energy. To move, the car must fight aerodynamic resistance (or “wind resistance”) and rolling resistance. When you stop, the brakes create waste heat to slow the car down.

Chances of crashing vs difference from flow of traffic. Texas Department of Transportation, modified by Jennifer Sensiba.

Aerodynamic resistance increases the faster you go, with big gains starting to pile up above 55 MPH. After that, each extra mile per hour of speed adds more resistance than the last. In the end, the best thing most people can do is slow down. Just be careful to not go too slow, because chances for an accident actually increase faster for slow drivers than fast drivers. If you can’t stay close to the flow of traffic, pick a different road where drivers go slower.

Rolling resistance is mostly related to your tires. Higher inflation (within safe limits) reduces rolling resistance. Also, some tires are made from special low resistance compounds that help the car use less energy going down the road. If your car came with those tires, be sure to buy the same tires again or tires with less resistance. If your car doesn’t have low resistance tires, be sure to get some the next time you need tires.

Finally, try to avoid braking as much as possible. You already spent the gas to get your car up to speed, and to stop the car, that energy has to go somewhere. When the brake’s pads grab the disc (or push against a brake drum on some cars), the brakes get very hot. All you’ve done is turn all the gas you used into heat and thrown it away.

To avoid braking, get your foot out of the gas sooner. Try to look ahead for things you might need to stop for and start coasting early. The aerodynamic and rolling resistance will gradually reduce your car’s speed. Depending on the car, you might get near-infinite MPG for longer by downshifting some to help slow down more.

When going down hills, there is rarely a good reason to use the brakes. Try to slow down a bit before the top of the hill or let the car speed up some going down the hill. For long, steep hills, switch the car to a lower gear so you don’t damage your brake system and risk failure.

Plan Ahead

The biggest thing you can do to reduce fuel use and environmental impact is to plan ahead.

Choosing your route when driving makes a big difference. For long drives, choosing a lower speed road instead of the faster interstates can save fuel, but only if there aren’t frequent stops. For city driving, think ahead about which places you want to go. Try to put the destinations in one big loop instead of bouncing around town like a pinball and racking up more miles. Start with the furthest destination first so that your car’s engine gets a chance to warm up and stay warm during all of the remaining stops.

Face-in vs Face-out parking. Illustration by Jennifer Sensiba.

Another thing to consider is parking. Avoid parking with the front in and having to back out later. When leaving a place, the engine will be at its coldest, so it’s best to spend as little time as possible sitting still or slowly backing out then. You might also be able to avoid backing in by finding a “pull through” space in a parking lot where you can pull in and leave the car’s nose facing out.

Also, consider which vehicle you’re using for the job. If you have a Toyota Prius and an F250 4×4, there are situations that would be best suited to each vehicle. If you’re getting groceries, take the Prius. If you need to pick up lumber at the home improvement store or need to haul a big camping trailer, take the F250. If you’re driving alone to work, take the Prius. This concept is known as “right sizing.”

There’s the old saw: “When you’re holding a hammer, every problem looks like a nail.” You may also want to ask yourself whether a car is the right choice at all for some trips. Is there environmentally friendly mass transit that can suit your needs? Or does the local fleet of big diesel buses never have more than 2 or 3 passengers, and thus is just adding to the pollution problem? Is the destination within walking distance? Biking distance? Might an electric scooter or e-bike do the job for this? Be sure to ask all those questions and make the decision that best fits your needs without wastefulness.

Final Thoughts & Resources

Before I wrap up, I want to give one word of warning. Be sure to not let saving gas lead to stupidity. When going down the road, there’s only so much you can pay attention to at once. Don’t let saving gas distract you from driving safely. If you feel overwhelmed or fatigued when focusing on saving fuel, take a mental break or even a break from driving. Be sure to watch for your limitations and don’t spend time beyond them.

If you’ve made it this far into this article and you’re still super excited about saving gas, then you are probably what we call a “hypermiler.” Don’t worry, it’s not a diagnosis. It’s a big community of vehicle efficiency enthusiasts and you’re invited to the party!

If you’d like to learn more, visit the following links:

EcoModder.com — A community of efficiency enthusiasts, including people who modify cars for better efficiency.

CleanMPG — A community of hypermiling enthusiasts.

Hypermiling International Facebook Group

Southwest Ecomotoring Club’s Eco Driver’s Ed — An online course that goes into much greater detail on the things in this article.

 
 





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About the Author

Jennifer Sensiba is a long time efficient vehicle enthusiast, writer, and photographer. She grew up around a transmission shop, and has been experimenting with vehicle efficiency since she was 16 and drove a Pontiac Fiero. She likes to explore the Southwest US with her partner, kids, and animals.



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