You don't necessarily need to spend a lot of money on a hybrid to drive green. Making even a small improvement to your car's fuel efficiency can make a big difference to the environment. Here are a few green driving tips to reduce the carbon footprint of the car that's already sitting in your driveway—and in the process, to save money.
Get a tune-up for the environment
Proper maintenance can have a big impact on how much gas you use. The payback for repairs varies, but fixing a serious problem like a malfunctioning oxygen sensor can improve fuel efficiency by as much as 40 percent.
Pay attention to your tires
The next time you need tires, consider buying low rolling resistance (LRR) tires. Rolling resistance is essentially the energy that your tires consume as they compress under the weight of your vehicle, and LRR tires can improve fuel efficiency by 1.5 to 4.5 percent.
Even with standard tires, proper inflation can make a big difference: The Department of Energy estimates that underinflated tires waste 1.2 billion gallons of gasoline per year. Once a month, use a gauge (not your eyes) to check each tire's pressure. (Most hardware and auto supply stores carry them for around $15.) You'll find the correct inflation number (noted as PSI, or pounds per square inch) in the owner's manual—don't go by the number listed on the tire itself, as that reflects the maximum pressure the tire can withstand.
And remember this green driving tip: The tire pressure fluctuates with the temperature. For every 10-degree drop in outside temperature, tire pressure goes down 1 PSI. So you may have to treat your tires differently in January than you would in June.
Lose the junk in the trunk
Here's a simple green driving tip: Those miscellaneous items that we all haul around can add up to lots of extra weight—and a hundred pounds equals about a 2 percent reduction in gas mileage.
Update your oil
Engines on newer car models (those less than 10 years old) often require lightweight oil such as 0W20 or 0W30. (The lower the number before the W, the easier the engine will start in cold weather. The number after the W represents the oil's thickness.) Not only will thicker oil reduce your car's fuel efficiency because more energy is needed to push through it, but the heavier oil can fail to lubricate the small spaces in a modern engine.
Adjust your octane
Many drivers (9 million by some estimates) mistakenly believe that pumping premium gasoline in their tank will help their engines run better; some drivers periodically opt for higher grades (91 octane and above), thinking it will help them clean out the car's fuel system. In both cases, this is a wasted effort. If your car wasn't designed to run on high-octane gas (94 percent of cars on the road today are designed to run on regular), using it will cause more unburned fuel to get into the emissions system, interfering with its ability to prevent noxious fumes. Premium gas also requires more energy to refine, so buying it when you don't have to is bad for the environment at both the production and consumption ends of the market.
Go green when you need to cool off
On short trips and when driving around town, keeping your windows down is more efficient than using the air conditioner. At highway speeds, use the air conditioner, as open windows and sunroofs create drag when you're moving fast. A green driving tip: Using the vents is the most fuel-efficient cooling option of all.
"Jackrabbit" starts and screeching stops are hard on your automobile and increase fuel consumption. Flooring the gas pedal just once can emit as much carbon monoxide as half an hour of normal driving. And slow down: Every car has an optimal range for fuel economy, generally from about 25 to 65 mph. (Check your owner's manual for this range.) For every 5 mph over this range that you drive, you're reducing fuel efficiency by about 7 percent.
Be eco-friendly, even when parked
Gas can evaporate even from a closed tank—and heat speeds up the process, so park in the shade when possible. By doing so, you'll also reduce the amount of energy needed to cool your car when you start driving.