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Are electric vehicles really green?

2023; Wiley; Volume: 43; Issue: 2 Linguagem: Inglês

10.1111/ecaf.12582

1468-0270

Richard J. Kish,

Recycling and Waste Management Techniques

Promoting the use of electric vehicles (EVs) is one of the key governmental initiatives for reducing harmful pollutants and combating climate change. But is this the best or most effective way to save the planet? EVs are touted for their eco-friendliness but are they really green? I discuss five reasons to question the ability of EVs to live up to the hype. The questionable green linkage includes electric sourcing (some of which is non-green); batteries (manufacturing, replacement, and disposal); reliance on subsidies (which may be directed at the wrong market segment); charging stations (including availability and costs); and whether alternatives would be a better choice for reducing the harmful effects on the environment. Electric vehicles do exceptionally well at reducing harmful toxins, but they have their drawbacks such as limited driving range and availability of charging options, especially for renters, who are not usually considered when evaluating the costs and benefits of electric vehicles. Electricity for powering electric cars and trucks comes from a variety of sources, not all of which are green. Key sources for electricity generation in the USA include coal, natural gas, nuclear energy, wind energy, hydropower, and solar energy (EIA, 2022a). Although coal is clearly not green, the other sources may also have non-green components, which will be discussed. Coal was the second-largest electricity-generating source at 21.86 per cent of the US marketplace in 2021. Natural gas, the leading electricity generating source, claims 38.44 per cent of the generating market. Coal, typically considered the dirtiest source, varies greatly by state and by electric company. Coal generation by states in 2021 ranged from a maximum of 90.63 per cent in West Virginia to a minimum of 0 per cent in Massachusetts, with a state average of 24.38 per cent. An example of an electric company mix is from Michigan's Detroit Electric (DTE) with a current fuel mix of wind 8.1 per cent, nuclear 18.7 per cent, natural gas 8.7 per cent, oil 0.2 per cent, and coal 64.3 per cent (see Table 1 and Table 2). Even with forecast changes through 2040, less than half of the total energy produced will be renewable (Riles, 2021). Renewable electric sources are not exempt from green drawbacks. The minerals needed for solar panels, wind turbines, and nuclear power have their own environmental issues. The extraction of the key materials used in renewables infrastructure (such as copper, lithium, nickel, manganese, cobalt, graphite, chromium, molybdenum, zinc, silicon, indium, boron, uranium, arsenic, aluminum, gallium, and titanium) can and do damage the environment. The mining operations for these materials have polluted the air, land, and water surrounding the mines. Without major modifications to mining operations (which do not seem to be a high priority within the mining firms), the environment will continue to be impacted negatively. Furthermore, it is nearly impossible to produce energy in a carbon-neutral fashion because even renewable energy has a carbon footprint as a result of the production and installation process. To determine a product or source's carbon footprint, a Life Cycle Assessment is carried out. This assessment takes into consideration the upstream and downstream greenhouse gas emissions. Upstream emissions are those that are released during the steps of production, such as mining and processing minerals, production, transportation, and construction. Downstream emissions are those released during the use of the resource and afterwards, such as maintenance, disposal, and decommissioning (Riles, 2021). In a scenario that meets the Paris Agreement goals, clean energy technologies' share of total demand rises significantly over the next two decades to over 40% for copper and rare earth elements, 60–70% for nickel and cobalt, and almost 90% for lithium. EVs and battery storage have already displaced consumer electronics to become the largest consumer of lithium and are set to take over from stainless steel as the largest end-user of nickel by 2040. ( IEA, 2022, p. 5) The many challenges confronting this transition in energy materials focus on two key areas: environmental and social. Environmental concerns revolve around five categories. First, climate change relates to the impact of key metals within the green revolution on greenhouse gas emissions. Second is land use and the environmental impacts of the mining of these key metals and minerals. Third is water management. Like mining, a large amount of water associated with the extraction and processing of these metals and minerals can have a huge environmental impact through wastewater and accelerating water stress in the areas where the mining and extraction processes are undertaken. The fourth concern is the hazardous waste generated and to properly dispose of it. Finally, the fifth concern revolved around social governance, that is, the sharing or lack of sharing of the rewards of mining and processing with the inhabitants of the countries in which the extractions take place. From the social aspect, two key areas of concern focus on health and safety and human rights. Health and safety deals with the plight of the workers and the hazards they face. Attention to human rights revolves around the exploitation of children and women associated with the mining and extraction industry (IEA, 2022, p. 40). The environmental concerns associated with EV batteries relate primarily to mining for the key minerals used in the batteries and with what happens to old batteries and the associated recycling hazards. The advanced batteries in EVs are designed for extended life, but will wear out eventually. Several manufacturers of EVs are offering eight-year/100,000-mile battery warranties. The National Renewable Energy Laboratory suggests that today's batteries may last 12 to 15 years in moderate climates (8 to 12 years in extreme climates) (Recurrent, 2021). But all-electric car batteries will inevitably degrade over time. Several factors that influence the rate of degradation include driving conditions, range of driving, recharging (from a high-charging versus a low-charging battery; avoid both extremely high and low battery levels), recharging source (AV versus DC), and slow charge (good) versus fast charge (bad). The entire battery replacement process is discussed by Najman (2022), who deals mostly with replacing batteries in the Nissan Leaf since it was the first electric car on the market and thus the only model that needs replacements outside warranties. One of the major concerns, other than cost, is the lack of mechanics who are properly trained to carry out replacements. Another concern is that the replacement batteries are mostly from salvaged cars, not new ones. Most cars need to have batteries from the same model cycle since the connections, shape, and size differ from one model cycle to another. Najman states that these factors have resulted in a waiting list for replacements. She also mentions that the cost breakdown is approximately 95 per cent for materials and only 5 per cent for the labour. What happens when the EV battery dies? Technically, the battery does not have to die; it just cannot recharge to provide an adequate range for the car to travel. Battery recycling focuses on one key economically recyclable material: cobalt. But there are others (such as lithium, manganese, and nickel) that are not as economically recyclable. How are batteries recycled? The two key methods are by extreme heat or acid, both potentially damaging to the environment. The first method, pyrometallurgy, uses heat to break down the material. This processing involves placing shredded EV batteries (called the black mass) into a furnace and using the organic burn-off as heat. The lithium that remains in the slag is expensive and difficult to remove. Cobalt and nickel are easier and cheaper to remove. The second process, called hydrometallurgy, also involves shredding the battery and placing the black mass in an acid bath to get rid of the non-metal components. Hydrometallurgy is less environmentally destructive. Both methods would become cheaper and more environmentally efficient if the production of EV batteries involved more standardisation, like lead batteries for gas-powered vehicles (Leber, 2022). Electric car sales are reliant on government subsidies. These subsidies are skewed towards the upper middle classes; they are of little value to people on more moderate incomes. The US federal Qualified Plug-In Electric-Drive Motor Vehicle Tax Credit is available for EV purchases from manufacturers that have not yet met certain thresholds of vehicle sales. It provides a tax credit of $2,500–$7,500 for new purchases, with the amount determined by the size of the vehicle and the capacity of its battery.1 Three key federal incentives are (a) the Electric Vehicle (EV) and Fuel Cell Electric Vehicle (FCEV) Tax Credit; (b) the Alternative Fuel Infrastructure Tax Credit; and (c) the Pre-Owned Electric Vehicle (EV) and Fuel Cell Electric Vehicle (FCEV) Tax Credit (for more details see Table 4). Nine states offer some sort of additional incentives – Arizona, California, Colorado, Oklahoma, South Carolina, South Dakota, Utah, Washington, and Wisconsin – as does the District of Columbia. Metz et al. (2021) advocate changing the incentive policies to encourage the superusers of gasoline-powered vehicles to switch to electric vehicles, since the top 10 per cent of drivers in terms of gasoline consumption burn 32 per cent of gasoline, which is more than the bottom 60 per cent of drivers combined. The superuser classification applies to drivers that consume more than 1,000 gallons of gasoline per year. This category of drivers typically drives three times more miles than the average driver, is more likely to drive pickups or sports utility vehicles (SUVs), lives in rural areas, and spends 8 per cent of their income on gasoline (which is more than twice the average driver). See Table 5 for a comparison of superusers versus the remaining drivers. One criticism of past and proposed carbon reduction policies is that the benefits will arrive too far in the future. For instance, increasing emission standards on gasoline-powered vehicles affect only new vehicles, which historically have an annual turnover rate of 6 per cent.2 Thus, Metz et al. (2021) propose a gasoline incentive of $10 per annual gallon consumed. This incentive structure would cover half the cost of the purchase price of a new EV for drivers classified as superusers. Coupled with fuel savings, this would incentivise these superusers to switch from gas-guzzling vehicles to a similar EV, especially with the increasing options within the light truck and SUV EV categories, which would match their existing preference for transportation. Thus, this policy would have a greater probability of achieving real reductions in carbon emissions in a shorter period. An analysis of the Ford F-150 Pickup Truck shows an average saving on fuel costs of $104.97 per 1,000 miles driven by the F-150 gasoline engine versus the F-150 electric version. This is based on the Environmental Protection Agency (EPA) miles per gallon estimates for the various F-150 2023 models, US gas prices per gallon, and US electric costs per kWh (see Table 6 for estimated EPA ratings by F-150 models). The EPA combined city and highway estimates range from 25 for the 2WD HEV (hybrid) 6-cylinder, 3.5 L engine to a low of 12 for the Raptor 8-cylinder, 5.2 L engine. The average cost of gasoline in the US on 9 January 2023 was $3.59/gallon, which ranged from a low of $2.89 on the Gulf Coast to a high of $$3.961 on the West Coast. Residential electric costs averaged $0.1372 per kWh, which ranges from a low of $0.0817 in Idaho to $0.3035 in Hawaii.3 The fuel cost saving per 1,000 miles driven by the F-150 model is shown in Table 7. The average saving per 1,000 miles driven was $104.97 using the average cost of gasoline, $85.32 using the lowest region's average cost, and $142.36 using the highest region's average cost. These savings do not account for the additional savings an EV user has over their counterpoint gas vehicle user in maintenance savings. Electric vehicles cannot run without charging stations. So, besides the need for charging stations, the key question that needs to be addressed is: who pays? Again, the need for charging stations limits access for poorer drivers since most do not own homes, where the primary charger (level 2 residential charger) would be located. Without a home, they have little access to charging stations. So what are the alternatives and their respective costs? A recent report from the renewable-energy-focused non-profit Rocky Mountain Institute examined the range of costs and found that the final bill will depend greatly on what kind of charging infrastructure is required. Basic level-2 commercial chargers range from $2,500 to $4,900 each, while DC fast chargers can cost anywhere from $20,000 to $150,000 depending on the speed and output power required. That's just for the chargers. To support these electrical chargers, the upfront costs for electrical transformers ($35,000–$173,000 each) need to be added, along with charging cables ($1,500–$3,500 each), credit card readers ($325–$1,000 apiece) and data/network contracts ($284–$490 per year per charger) (Nelder & Rogers, 2019). Table 8 provides a summary of these costs. The main cost components of EV charging infrastructure comprise procurement, requirements, and soft costs. Besides the charging hardware, procurement expenses include managing charging capability, contracts, software, grid hosting capacity, and make-ready infrastructure. Requirements include factors associated with payment systems, measurement standards compliance, compliance with the Americans with Disabilities Act, and parking requirements, dual plug types for direct-current fast charging, and cost standards. Finally, the soft costs, which include communications between utilities and providers, futureproofing, easement processes, and complex codes and permitting processes, are not easily quantified. These costs can add up fast. But it doesn't all have to be paid for by the distributor. There are various incentives, rebates, and grants from several different sources, not all government related. Should all the effects to reduce pollution and carbon emissions from vehicles target the electric car market? Alternative fuel sources are available, such as natural gas and biomethane (BioNGV). The first option, natural gas vehicles (NGV), has many green attributes: (a) it offers a 25 per cent reduction in CO2 emissions and a 95 per cent reduction in fine particles compared with gasoline vehicles; (b) natural gas already has an established distribution network; (c) natural gas is cheaper than conventional fuels (gasoline and diesel); (d) natural gas engines require less maintenance than combustion engines; and (e) natural gas vehicles have has a range of 250 to 300 miles, similar to EV, but without the long wait to refuel versus recharge. The second alternative, BioNGV, has similar characteristics to natural gas except that it is produced through the methanisation of organic waste; thus, it is a renewable fuel that also helps reduce the amount of waste that goes to landfills. When used as a liquid fuel, its carbon footprint is 80 per cent lower than that of conventional fuels during its production, and it generates little odour and only trace amounts of nitrogen oxides. It is currently being used in some metropolitan public transportation vehicles. Vehicle range is similar to the range from NGV (SNECI, 2021). There are two other possibilities: hydrogen and biofuels (ethanol and ethyl tert-butyl ether, ETBE). They have potential, but in their current state of development are not considered viable options. For instance, hydrogen vehicles (HV) do not run on internal combustion engines, but on electricity that is produced from the hydrogen. Like the other alternatives, they would be refueled from a pump. The key benefit of HVs is that the only emission would be H2O (water). The range of HVs (375 miles) is typically longer than EVs (250–300 miles). The major hurdle for HV is obtaining the hydrogen, which uses either steam reforming or electrolysis of water. The former relies on a reaction between steam and either coal, oil, or natural gas to release hydrogen, but also carbon dioxide. The latter involves breaking down water into its two parts (oxygen and hydrogen). Unfortunately, this process generates toxic by-products and is not yet economically scalable. Biofuels (ethanol and ETBE) are combined with gasoline to fuel the current combustible engine to produce less pollution. Electric vehicles offer significant emissions benefits over conventional vehicles; but are they the best option? As I have pointed out, EVs are not totally green. Yes, EVs are much greener than their fossil fuel counterparts. But their environmental benefits are highly dependent upon factors directly involved in their manufacture and their changing source. From the manufacturing side, the key factor is the battery and its need for key minerals such as highly toxic lithium. The battery also has potential problems with the difficulty of recycling or proper disposal. But recycling and disposal issues are also found with conventual vehicles. From the charging source, there are both high- and low-pollution options; for example, coal (high) and solar (low). But even the low-pollution sources have polluting aspects arising from the manufacturing of the components and the associated storage units (i.e. large-scale battery farms). But conventional vehicles have their own set of environmental concerns associated with power sourcing. A major concern detailed here is the reliance of EVs on government subsidies primarily for the purchase of vehicles and the installation of adequate charging stations. But if governmental units wish to steer the motoring public to a friendlier environmental option, there will always be trade-offs. Nevertheless, governmental units must not stress just one option for a greener environment, since there are many viable alternatives. Thus, the primary focus on EVs over alternative transportation technologies vehicles for reducing pollutants, some which may be more cost-effective in the long run, need not be short-sighted. There is more than one way to generate green transportation. EVs have shown great potential, but to meet the hype there needs to be a more proactive approach across the entire EV supply chain.