Environmental Impacts of Electric Vehicles

Environmental Impacts of Electric Vehicles

Early adopters of electric cars are often motivated by environmental concerns. EVs differ from gas-powered cars in producing no tailpipe emissions or engine noise. This is particularly helpful to people who live near roads and therefore suffer from higher levels of respiratory diseases, developmental impairment (from noise and airborne toxins), and stress from noise. The switch from gasoline fuel to electricity has many ramifications, and most depend on what electricity-generating fuel is replacing the gasoline.

For example, if coal is being used to generate the electricity to power the car, the improvement in urban air quality where the vehicle is being driven is appreciably offset by the increase in coal- or gas-fired pollution near the power plant, coal mining pollution, gas well pollution and methane release, and land destruction near the wells/mines. If many more people live in the area where driving occurs than where power is generated, there may be a net improvement in human health from vehicle electrification, but the benefits of vehicle electrification will be greater and more uniform where power is generated from non-polluting sources such as wind, solar, hydro, or nuclear sources. In the Four Corners, some EV owners generate their own power using solar or buy shares in the community solar gardens enabled by La Plata Electric Association.

Power plant in desert

Many studies have been conducted to calculate the trade off between power production in automobiles and those in power plants (Here’s one from Argonne National Laboratory). These studies found the reduction in energy use and air pollution associated with vehicle electrification ranges from minor (where electricity is generated primarily by coal) to profound (where electricity is generated by cleaner sources), but in every state there is a benefit.

For example, in Utah, the most coal-oriented of the Four Corners’ states, the federal well-to-wheels (all aspects accounted for) energy emissions calculator based on the 2018 fuel mix estimates that an electric car driven for an average year generates only 65% of the carbon pollution (measured as CO2e or carbon dioxide equivalents) as does a conventional car. In Arizona, which uses less coal, the electric vehicle is estimated to produce only 38% of the carbon pollution of the gas car. One observation helps explain this. Exploring, drilling, transporting and refining gasoline for cars and trucks requires a lot of energy, either in the form of electricity or atmosphere-damaging oil and gas wells. Therefore reducing the consumption of gasoline also reduces the demand for electricity and other energy sources.

Some have claimed there is a 1:1 swap between the electricity needed for driving one mile on gasoline or driving an electric car for one mile. This is an oversimplification of a very complex tangle of energy uses. A variety of conclusions can be reached from simple computations of energy inputs, but the situation is sufficiently complex and opaque (industries are loath to share hard data) to prevent a clear general answer. Nonetheless, the energy consumption involved in producing gasoline is quite substantial, and the switch from gasoline to electric propulsion of a car would entail much less increase in the production of electrical power if the production of gasoline was reduced equivalently.

Furthermore, personal vehicles can usually be charged at a time of day when electricity supply exceeds demand (the car’s charger can be programmed to use juice when surplus power is available). Thus the new power needed for electrification of transportation is moderate or in some cases negligible. For this reason many electrical utilities are promoting “beneficial electrification” as a tool to reduce electrical rates ($/kwh) for everyone. Electric car owners will pay the same fee per kwh as most other residential users, but by using power when it is in surplus, they will reduce the fees the utility must pay to power plant operators for peak power.

How charging EVs during the day would ease the electric grid’s conversion to renewable energy.

If every car and light truck were instantly converted to electrical propulsion, and the grid had no time to adapt (and petroleum facilities did not ramp down their power consumption in response to reduced demand), the US electricity infrastructure would already have the capacity to meet about 73% of the automotive energy needs according to a 2004 federal study . Since that study was completed, the grid has become cleaner and more resilient through fuel switching and infrastructure build-out. Newer charging systems are also making it possible for the hosting utility to briefly pause car charging until after a peak in grid electricity demand has subsided. This feature is incorporated into the subsidy that Colorado’s La Plata Electric Association utility provides for residential electric vehicle chargers.

The Bottom Line

Electric vehicles reduce greenhouse gases, noise, smog, particulates, nitrates and other airborne toxins that shorten lives. By reducing dependence on petroleum production, electric cars reduce the water and air pollution associated with that industry. In the US in 2018, 79% of petroleum energy products were used solely for transportation . Therefore, adoption of vehicle electrification will greatly reduce the environmental damage caused by oil spills, drilling, pipelines, refineries and other petroleum industry infrastructure. If no other change occurred, this would be magnificent, but would be to some degree offset by the production of dirty power plant fuels, especially coal. Fortunately, the costs of cleaner power plants have now dropped below that of coal plants, and coal generation is being rapidly eliminated by market forces.

What about the impacts of manufacturing EVs?

Workers in auto company.

In addition to the environmental costs of power generation, electric cars also impact the environment through the manufacture of the vehicles themselves, and the disposal of the vehicles or batteries at the end of their usable lifespans. In many respects the manufacture of conventional gas cars and electric cars are similar (fenders, brakes, drive shafts, upholstery, etc), with the exception that electric cars use batteries (at the present time all car propulsion batteries are lithium-ion) and electric motors.

The mining of lithium, nickel, and cobalt has drawn special concern, as most such mining today occurs in countries where environmental regulations may be lax and miners are paid and protected poorly. This is an issue that has not been resolved satisfactorily. Lithium is not a particularly rare element and could be mined in adequate quantities in most countries. We will see whether the car and phone manufacturers address the inequities in the supply chain for these critical compounds. See the Dec. 2019 blog story about a new lithium-ion battery being developed by IBM that replaces the nickel and cobalt with iodine that is inexpensively obtainable from seawater.

How can the batteries be disposed of?

Lithium Mine in Western Australia from https://www.miningglobal.com/

The disposal of lithium-ion batteries is an issue. To date the industrial reuse/recycling/disposal of these has been hard to assess because so few car batteries have reached the end of their transportation lives. The reuse and recycling industry has not yet had the opportunity to develop. At present, there is ample demand for batteries that have lost some capacity, which reduces their power-to-weight ratio and makes them less useful for transportation purposes. Vehicle batteries with reduced capacity are ideal for reuse as stationary battery storage, such as for homes and solving local power storage needs for the electrical grid. Much remains to be learned about the uses and costs of reusing and recycling lithium-ion batteries, but this is unlikely to be a serious challenge to the adoption of electric vehicles as there are so many unmet needs for stationary power storage.

In the event that spent automotive batteries become completely non-functional, Nissan claims in most cases the constituent materials can be recycled.