Climate issues can be difficult to understand. This series is designed to provide you with the information you need to know about some of the most prevalent issues in climate policy today. In 1,000 words, let’s learn how life cycle analysis works.
This article is written by Kaleigh Pitcher, a Policy Consultant at Save the Sound, working primarily in climate and environmental justice advocacy. She has a Master’s of Public Policy with a focus on Health and Social Policy from the University of Connecticut.
Electric Vehicles
As we see more electric vehicles on the road, you might be considering purchasing one. There’s a lot of conversation about the merits of internal combustion engine (ICE) vehicles versus electric vehicles, with conflicting conclusions of which is cheaper, more fuel efficient, or better for the environment. Fortunately, there is a quantifiable way to assess your vehicle’s environmental footprint: life cycle analysis.
What is life cycle analysis? Life cycle analysis evaluates the environmental impact a vehicle will have over the course of its manufacturing and use. It can be broken down into raw material extraction, manufacturing, operating emissions, and final disposal. By estimating the effect at each stage, we can quantify a vehicle’s lifetime impact on the environment.. Let’s compare.
Raw Material Extraction
Electric and ICE cars all begin the manufacturing process with the acquisition of raw materials. Most vehicles, despite their fuel source, require similar amounts of metal, glass, and rubber. The primary difference between EVs and ICE vehicles is their battery and how it is made.
EVs primarily use lithium-ion batteries, like those in our phones, laptops, and other electronics. ICE vehicle batteries are typically lead-acid batteries.
Both lead and lithium are mined from the earth. In fact, lithium is the 33rd most abundant element in the earth’s crust. Lead is the 37th most abundant, but it is easier to mine, as lithium is often found in small quantities across a larger area, while lead is generally found in larger deposits.
ICE vehicles also require petroleum extraction for fuel. A study by the International Energy Agency found that in 2022, the production, transport, and processing of oil and gas resulted in 5.1 billion tons of CO2-equivalent emissions. Oil and gas production account for almost 15% of all energy-related greenhouse gas emissions. It’s important to note that these are not tailpipe emissions—these are the extraction and processing emissions associated with gasoline before it ever reaches a car.
Manufacturing
Vehicle assmbly differs primarily in their engine and battery systems. An ICE vehicleproduces an estimated 5.6 metric tons of CO2 in production, compared to 8.8 metric tons for an electric vehicle. For EVs, this figure represents almost half of its lifetime emissions, and for gas powered vehicles, it represents less than a quarter. Like most investments, there are initial costs in the short-run that lead to more benefits in the long-run.
The EPA dispelled the myth that manufacturing emissions render EVs worse than gas vehicles. An EV’s lifetime emissions are lower than the average gas-powered vehicle—including the manufacturing stage. The typical break-even point is about 15,000 to 20,000 miles, or roughly one year of vehcile ownership, after which gas vehicles will overtake EVs for lifetime emissions.
Use & Emissions
Once the vehicle reaches the consumer, its environmental impact primarily comes from fuel usage. Emissions are measured in two ways: tailpipe emissions and emissions generated from refueling.
EVs are typically charged at home, siphoning power from the electric grid. Vehicle emissions can differ based on how the electric grid is powered, but EVs remain significantly more fuel efficient than gas powered vehicles. This tool allows you to compare the standard gas powered vehicle’s fuel efficiency to an EV based on location and the model of the car. Our region’s grid is supplied largely by natural gas and nuclear power, which are cleaner than coal and oil, but there’s still progress to be made. As more of our electric supply comes from renewable energy like solar and offshore wind, the emissions associated with charging will decline because they are from a less carbon intensive source.
Pollution can be compared between electric and gas vehicles by looking at MPG-CO₂e, or “miles-per-gallon carbon dioxide equivalent.” This can be used to show how fuel efficient a vehicle is in proportion to its CO₂ emissions. For example, gas vehicles run at about 25 MPG on average. A hybrid runs at about 51 MPG-CO₂e, and an all-electric car runs at 96 MPG-CO₂e— a staggering figure in comparison to gas vehicles. EVs can drive four times as many miles to produce the same amount of emissions. This figure comes from the emissions rendered from the electric grid while charging, not directly from driving. Electric vehicles have no tailpipe emissions.
Gas vehicles have emissions both from their fuel source and from the tailpipe. The Environmental Protection Agency (EPA) found that a typical passenger vehicle not only emits 4.6 metric tons of CO₂ per year, but also releases methane and nitrous oxide into the atmosphere. There is an added environmental cost in the transportation of fuel to gas stations, as well as the emissions associated with gasoline production, which were mentioned at the raw materials stage. The transportation sector accounts for almost 30% of greenhouse gas emissions in the United States, and over 94% of fuel used for transportation is petroleum based. As consumers move away from gas-powered cars, we can expect this figure to decline.
Final Disposal
The shells of gas and electric vehicles are relatively comparable; both contain a lot of material which can be repurposed or used for scrap metal. Their batteries are a bit different.
Given the known dangers of lead, nearly all lead-acid batteries are recycled. While far less lithium-ion batteries are recycled, there is great potential for industry recycling through scientific innovations and policy opportunities. Recycled lithium can be used to create new EV batteries, but this is not yet the norm. According to Scientific American, recycled lithium-ion batteries can perform even better than newly manufactured ones. While many states require that gasoline car batteries be recycled, no such policies exist for electric vehicles. California is currently considering EV battery recycling requirements.
Vehicle innovations must bring new policies for regulation and consumer protection, like in Connecticut’s newest regulatory package for Cleans Cars and Trucks, which establish stronger emissions standards and electrification targets.
Conclusion
Over the course of the vehicle’s life, electric vehicles have a significantly lower environmental impact. The graph above from the International Energy Agency shows the lifetime emissions in metric tons of each vehicle, with the orange and yellow bars representing electricity and gas, respectively. Gas vehicles were found to have produced about twice as many emissions over its lifetime.
Life cycle analysis is an important tool in assessing environmental impact. By quantifying the emissions a car will produce over its lifetime, we can validate that EVs have a smaller carbon footprint than gas vehicles. These assessments can help the transportation industry and legislators forge policies that promote cleaner energy vehicles, and can help consumer make choices about their own impact.