Maximizing Environmental Benefits of Electrified Vehicles

Full battery electric vehicles (BEVs) are considered “zero emission” because they don’t release greenhouse gases or other pollutants during use. But that term can be misleading, because it takes electricity to charge the vehicle, and the power plant generating the electricity may also generate incremental emissions. Electric vehicles do reduce pollutants generated by burning petroleum fuel in the vehicle in proportion to the reduction in vehicle fuel consumption. However, replacing gasoline with electricity generated from coal, for example, results in emissions at the power plant, including carbon dioxide, nitrous oxides, sulfur dioxide, volatile organic compounds, carbon monoxide and particulate matter. As a result, the environmental benefits of BEVs and plug-in hybrid electric vehicles (PHEVs) depend largely on the fuels used to power the electrical grid. Operating a PHEV or BEV on the current average U.S. electrical grid, which relies heavily on coal power, has little emission advantage over a hybrid electric vehicle (HEV). (See the well to wheels carbon dioxide (CO2) emissions figures on the Comparing Electrification Technologies page.)

Plug-in vehicles could help to reduce overall CO2 and other emissions if the electricity used to charge them were generated from cleaner fuels, and ideally renewable resources, which produce significantly fewer emissions than the coal and natural gas that are often used for power generation. In addition, “smart grids” that include grid-to-vehicle communications would enable utilities to make more-efficient use of electricity supplies, thereby potentially reducing emissions and electricity costs.

Energy Security Benefits of Electric Vehicles

The current energy demand for transportation is almost exclusively met by petroleum. In the U.S., for example, approximately 94 percent of transportation energy demand is provided by petroleum. The near-complete dependence of a vital economic sector on an import-dominated energy resource is clearly an issue of concern. One of the major benefits of increasing the proportion of electrified vehicles in the U.S. fleet is that it will diversify the transportation energy demand and provide increased energy security. HEVs reduce petroleum demand by increasing efficiency. PHEVs reduce petroleum demand due to increased efficiency and also switch some of the energy demand from petroleum to other sources. BEVs remove entirely the need for petroleum.

To realize the potential benefits of vehicle electrification, a range of issues must be addressed, including strategies to maximize their environmental benefits. Vehicle and fuel technologies interact in a complex system that includes vehicle technologies, battery technologies, fuel types and energy-generation technologies, all of which determine potential impacts on the environment and energy security.

Ford alone cannot solve these issues. However, we are working with partners, such as utilities, to make a contribution to maximizing the environmental benefits of electrified vehicles. We are also implementing technologies that will help customers drive their electrified vehicles to maximize efficiency, increasing other green features of our electric vehicles and implementing green manufacturing processes at our electric vehicle plants.

Maximizing Vehicle Efficiency

Electric vehicles are inherently more efficient than gasoline vehicles. Electric motors are more efficient in converting stored energy into vehicle propulsion than traditional internal combustion engines. Internal combustion engines can typically only use about 15 percent of the onboard fuel energy to power the vehicle, while electric motors have nearly 80 percent onboard efficiency. In addition, electric-drive vehicles do not consume energy while at rest nor coasting, and as much as one-fifth of the energy typically lost when braking is captured and reused through regenerative braking.

Ford has made it a priority to further maximize the efficiency of our electric vehicles. We optimized every system in the vehicle to ensure it would be as “electron efficient” as possible. In addition to using the latest technology for the battery and the rest of the electric-drive components, we have maximized efficiency through improved aerodynamics and low rolling resistance. In addition, we used our knowledge from two generations of hybrid electric vehicles to enhance the Focus Electric’s range and efficiency through regenerative braking.

Maximizing Driving Efficiency

Our in-vehicle information systems also help drivers maximize their own driving efficiency to further increase the distance they can go on a single charge and reduce the overall costs of operating an EV. As described in Living the Electric Lifestyle, our electric vehicles can coach drivers how to drive more efficiently by changing their driving style, maximizing regenerative braking or minimizing the use of air conditioning. The vehicle information systems also provide information on range and vehicle energy use to help drivers track and maximize their driving efficiency.

Maximizing Charging Efficiency

The most important strategies for maximizing the efficiency and environmental benefits of electric vehicle charging require changes to the electrical grid and the fuels used to power it. Both increasing the use of renewable energy sources and investing in smart grid technologies will help to improve the environmental benefits of EVs. Many of these issues are beyond Ford’s control. However, Ford is working with utilities and municipalities to make the most of electric vehicles’ advantages. We are also doing what we can to provide efficient and environmentally friendly charging options.

  • Using renewable energy: Recharging using electricity generated by renewable energy sources (such as solar, wind, hydropower or biomass) can cut CO2 emissions dramatically. Smart vehicle-to-grid communication can help utilities better use renewable energy sources. For example, it can allow vehicles to recharge when wind power is most available (usually at night) or during the day from solar arrays, depending on the renewable source available and its output. As the power-generation sector continues to improve its fuel mix, the environmental impact of driving a plug-in vehicle will diminish substantially – perhaps even toward zero.

    Adding more renewable fuel sources to electrical grids will take time. Ford is working with utility partners to develop home-based solar recharging stations that will allow EV owners to obtain the power they need to charge their vehicles from renewable sources, even if the overall electricity grid powering their home has not shifted to renewable.

  • “Smart grids and smart charging:” The development of “smart grid” technologies, which can provide utilities and customers with real-time information on energy use and energy prices, is a key enabler of efficient integration of electric vehicles and grids, and an important strategy to maximize EV efficiency and environmental benefits.

    Smart grids will help make the electrical grid and electrical vehicle charging more efficient by channeling vehicle recharging to times when electrical grid resources are currently underutilized. Since demand for electricity fluctuates (generally peaking in the afternoon and dropping off at night), utilities typically use a mix of fuels and power plant types to meet demand. That means the environmental impacts of electric vehicle use will vary depending on where and when the vehicles are charged. During certain seasons and particularly at night, utilities generally have excess generation capacity – unused resources that create financial inefficiency. Charging PHEVs and BEVs during these off-peak hours, when this excess capacity is available, can increase the overall efficiency of the electric grid – potentially reducing CO2 emissions, as well as the cost of electricity. But if PHEVs and BEVs are charged at peak times, that could create increased CO2 emissions from power generation and also create demand for additional power plants. Utilities have a role to play in educating electrified-vehicle users and providing them with incentives to charge their vehicles at the most beneficial times.

    With all these variables, utilities will be key partners in defining and developing electricity supply systems for electric vehicles that are efficient, affordable and environmentally sound. That’s why Ford has partnered with several utilities throughout the U.S. and Canada, as well as with the U.S. Department of Energy, for its PHEV pilot program. For more information on our work with utilities, please see Collaborating with Utilities and Municipalities.

  • Value Charging by Microsoft, which is available first on Ford U.S. vehicles, also helps to maximize the efficiency of charging and the environmental benefits of EVs. This system communicates with local utilities to find off-peak times to charge, which helps to prevent the need for infrastructure upgrades to support added energy demand and reduce the production of additional CO2. Ford and Microsoft plan to continue to work with utility partners and municipalities to help further develop systems to maximize the effectiveness of electric vehicles and their interaction with the electricity grid.

A Holistic Environmental Approach

Reducing emissions and maximizing vehicle efficiency are just some of the elements of our strategy to maximize the environmental benefits of EVs. We are also using green power and green technologies to manufacture our EVs, and we are using green materials in our electrified vehicles and charging stations. The Michigan Assembly Plant, for example, which will produce the Focus Electric, C-MAX Energi and C-MAX Hybrid, in addition to the standard gas-powered Focus, will be powered by the largest solar array in the state of Michigan. We have partnered with DTE Energy to build this solar panel system at the plant. We are also working with DTE Energy to develop a stationary battery energy storage system that will store excess power produced by the solar array until it is needed in the plant. This battery storage system will use electric vehicle batteries that have reached the end of their useful lives in vehicles. This approach provides a second life for vehicle batteries, which reduces waste and maximizes the efficiency of solar power. The plant also draws power from local landfill gas, making productive use of methane generated from decaying trash, which reduces emissions of this potent greenhouse gas. The plant also uses solar-powered tugs, which move vehicles and parts around the plant. See the Michigan Assembly Plant case study for more details on these green manufacturing strategies.

Ford is also using green materials in our HEVs, BEVs and PHEVs, as well as many of our other vehicles, to further maximize their environmental benefits. For example, our existing HEVs use recycled-content seat fabrics. The Escape Hybrid, as well as the gas version, has been using soy foam seats for several years. Starting in 2011, all of our U.S. vehicles will use soy foam, including the Focus Electric. The Focus Electric will also use a material called Lignotock behind the cloth on the door. Derived from 85 percent wood fibers, this renewable material reduces weight and provides better sound-deadening benefits compared to conventional glass-reinforced thermal plastics. In addition, the vehicle-charging stations we developed with Leviton use 60 percent recycled materials. For more information about our use of green materials in vehicles, please see Sustainable Materials.