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Details to know

• Impact of burning fossil fuels
• What to look for in a fuel-efficient vehicle
• Hybrid Electric Vehicles
• Other Fuel-Efficient Vehicles
• Alternative Fuels

Impact of burning fossil fuels

Energy is needed to power vehicles and thereby transport goods and people from point A to point B. Until recently, the majority of the energy used to power vehicles has come from the burning of fossil fuels in a combustion engine.

Burning fossil fuels produces carbon dioxide (CO2) emissions (known as greenhouse gases or GHG) which trap heat in our atmosphere thereby increasing the earth’s temperature and contributing to climate change. Emissions pollute the air and form smog which affects the air quality and the health of living creatures and our environment. Emissions also contribute to the formation of acid rain, the effects of which are felt by fish populations, trees, plants, and soil.

What to look for in a fuel-efficient vehicle

Consumers today have many more fuel efficient vehicle choices available to them. Consider the following information before you make your next vehicle purchase:

• Newer vehicles tend to be more fuel-efficient than older models but it’s important to compare fuel consumption ratings just to be sure. Look for the EnerGuide label on new cars which shows city and highway fuel consumption ratings and estimated fuel costs.
• The Ministry of Natural Resources’ Office of Energy Efficiency has compiled a fuel consumption rating guide for passenger cars and a list of the most fuel-efficient vehicles:
  • Download the Fuel Consumption Guide
  • Download the list of the most fuel-efficient vehicles
• The shape of the vehicle plays an important role in fuel efficiency -- aerodynamic vehicles reduce drag and wind resistance. A streamlined design will provide better fuel efficiency because air will pass over the vehicle more easily.
• The heavier the vehicle, the more energy required to propel it forward so note the vehicle’s overall weight and consider passing on those luxury extras like power seats and sunroofs that add extra weight to your vehicle.
• Consider whether you really need a 4X4 or an all-wheel drive vehicle because the weight of those components increases fuel consumption.
• The thickness of the tire affects the vehicle’s rolling rate. The thicker the tire tread, the higher the rolling resistance and therefore the higher the fuel consumption.
• A manual transmission, especially a 5 or 6-speed transmission, used correctly can use less fuel than an automatic transmission. You can ensure you’re shifting gears at an optimal level by watching your tachometer. For maximum fuel efficiency, change gears at 2,500 RPM.
• Some newer cars are outfitted with a "real time" fuel consumption gauge which provides the driver with real-time fuel-efficiency and average efficiency readings so that the driver can instantly see an increase in fuel consumption reflected on the gauge.
• The more gears in a transmission, the more fuel efficient the vehicle will be. There are some new features in automatic transmission vehicles to look for:
  • Electronically shifted manual transmissions (ESMAT) or Automated Manual Transmission (AMT) – combine the best features of manual and automatic transmissions. The clutch and shift operations are managed automatically by onboard electronics.
  • Aggressive Shift Logic – provides two modes: sport and economy. Sport mode changes the up and downshift points for maximum acceleration. Economy mode ensures the transmission shifts at a lower speed to optimize fuel efficiency.
  • Continuously variable transmission (CVT) – this automatic transmission works to match the engine power to the power demand at the wheels and ensures optimal engine operating.
• The larger the vehicle’s engine and the more cylinders it has, the greater its fuel consumption. More efficient engine design in recent years has meant that smaller engines today can meet the demand for power because of technologies like fuel injection, improved combustion chamber design, and exhaust gas recirculation to name just a few.
• Diesel engines work more efficiently than gasoline engines and require less fuel to power the engine. The carbon content of diesel is higher than gasoline but because you’ll use less fuel than gasoline, the overall emissions are about 20% less than a gasoline engine. New diesel engine technologies have eliminated previous issues of excessive engine noise, vibration, poor acceleration, dirty exhaust and poor cold weather performance. Lower sulfur levels in diesel fuels have also improved emissions.
• Look for vehicles that offer more battery-powered accessories like power steering and air conditioning, which don’t rely on power from the engine thereby saving fuel.

Hybrid Electric Vehicles

Hybrid Electric Vehicles (HEVs) refer to the combination of an internal combustion engine and an electric motor powered by a battery that delivers power to the drive shaft.

HEVs reduce fuel consumption by switching to the battery to power the car when it’s running at low speeds or idling. By using power from the electric motor, there is less demand on the combustion engine and therefore less fuel consumption.

HEVs utilize the following fuel-saving features:

• Idle-Off allows a vehicle to turn off its gasoline engine when stopped, thereby saving fuel. In a well-designed system, the engine will turn back on and be ready to go in less time than it takes to move your foot from the brake to the gas pedal.
• Launch Assist is the feature where the electric motor helps to get the vehicle quickly moving again when the driver accelerates after the car has been stopped. This feature reduces amount of work done by the internal combustion engine.
• Regenerative Braking converts energy lost through friction during braking and decelerating into electricity to recharge the battery.

The HEV electric motor provides extra power allowing for a smaller combustion engine that can maintain an acceptable level of acceleration. But not all hybrids are created equally - the more powerful the electric system or the strength of the battery pack, the less reliance there is on the combustion engine. There is a wide range of hybrids offering varying levels of non-combustion power:

• Parallel or "Full" Hybrid
  The parallel hybrid system allows power to the wheels to be delivered by the engine and the electric motor at the same time.
• Series or "Mild" Hybrid
  In a series hybrid, the electric motor exclusively powers the wheels without the help of the combustion engine. The engine is responsible for producing electricity which is stored in the battery and used up by the electric motor.
• Series-Parallel Hybrid (Power Split)
  A combination of the parallel and series systems, the combustion engine delivers power to the wheels as well as producing electricity, which is stored in the battery. The battery supplies electricity to the electric motor which delivers power to the wheels. The real advantage of the series-parallel system is that the combustion engine and the electric motor are connected to a “planetary gear” system that allows for any combination of gear ratios, which in turn allows the engine to run at the most efficient speed.

Other Fuel-Efficient Vehicles

Hybrid Electric Vehicles are not the only fuel-efficient alternative on the market, there are other vehicle and fuel alternatives available and we’re hearing more about these every day:

Plug-in Hybrids
Plug-in hybrids can be one of any of the 3 hybrid architectures and have a larger battery pack that can be charged by plugging the power cord into an electrical outlet, hence the name “plug-in”. Plug-ins get their energy via electricity from “the grid” or electricity network, thereby reducing greenhouse gas emissions. Because more energy is stored in the larger battery, plug-ins can drive for a certain distance in an all-electric mode. The Chevrolet Volt is poised to become one of the first extended-range electric vehicles.

BlueTEC
BlueTEC is currently the cleanest-burning diesel engine in today's passenger-car market and was developed by Mercedes-Benz. BlueTEC technology features an innovative exhaust gas treatment system that is 20 to 40% more fuel-efficient than a comparable gasoline engine. Ultra-low sulphur diesel (ULSD) fuel is a precondition for the optimal effectiveness of BlueTEC. BlueTEC technology reduces the nitrous oxide to harmless nitrogen and water vapour – gases that occur naturally in the air we breathe – thereby drastically reducing soot, pollutants and greenhouse gas emissions that cause global warming.

Carbon Fibre Body Construction
Another way to reduce fuel consumption is to reduce the size of the vehicle and make it more aerodynamic so it requires less fuel to be propelled forward. Using carbon fibre in the vehicle’s body construction significantly lightens the vehicle, plus, carbon fibre is a material that is extremely durable. However, carbon fibre is expensive to produce and until the cost of manufacturing it goes down, it’s not a realistic vehicle material for use in mass-production.

Alternative Fuels

Here's a quick overview of just some of the new fuel and power sources that are used in today's vehicles and beyond:

• Ethanol (ethyl alcohol) gasoline blends are liquid fuels that can be produced from corn, agricultural and forestry wastes or natural gas. However, concerns have been raised related to the large amount of arable land, fertilizer and other resources required to produce enough for demand, resulting in negative impacts on global food supply as well as the energy and pollution balance of the whole cycle of ethanol production.
• Cellulosic ethanol is a type of biofuel produced from lignocellulose: a structural material that comprises much of the mass of plants. Switchgrass and Miscanthus are the major biomass materials being studied today, due to their high productivity per acre.
• Biodiesel is made from the oils and fats of plants and can be used alone, or blended with conventional petrodiesel in most modern, unmodified diesel-engine vehicles.
• Natural gas can be up to 40 per cent cheaper than gasoline, plus it produces fewer emissions. To use natural gas as a transportation fuel, you can either convert existing gasoline vehicles or purchase factory-produced natural gas vehicles.
• Propane is the most common alternative fuel in Canada. Similar to natural gas, propane is used as a transportation fuel either by converting existing gasoline vehicles or by purchasing a factory-produced propane vehicle.
• Hydrogen is the cleanest fuel in the world. Fuel cells generate electricity by electrochemically combining hydrogen and oxygen. On a life-cycle basis, they can produce zero or very low greenhouse gas emissions, depending on the source of the hydrogen. Fuel cell technology is not yet commercially available; one of the reasons is due to the lack of hydrogen infrastructure.
• Ultra-Low Sulphur Diesel (ULSD) is a fuel that has been refined so that the sulphur content is 15 parts per million or less, which is 97% cleaner than the standard highway-use diesel fuel sold in North America, which contains an average of 500 parts per million of sulphur. Sulphur, a natural part of the crude oil from which diesel fuel is derived, is one of the key causes of particulates or “soot” in diesel. Soot is the main culprit of diesel engines' noxious black exhaust fumes, and is among the prime contributors to air pollution. Ultra-low sulphur Diesel has been the norm in Europe for several years. By December 2010, all highway-use diesel fuel offered for sale in the U.S. must be ULSD fuel.