Environmental aspects of the electric car

Battery electric cars have several environmental benefits over conventional internal combustion engine vehicles (ICEVs), such as:

• Elimination of harmful tailpipe pollutants such as various oxides of nitrogen, which kill thousands of people every year[9]
• Less CO
  2 emissions globally than fossil-fuelled cars, thus limiting climate change[10]

Plug-in hybrids capture most of these benefits when they are operating in all-electric mode.

Electric cars have some disadvantages, such as:

• Reliance on rare-earth elements such as neodymium, lanthanum, terbium, and dysprosium, and other critical metals such as lithium and cobalt,[11][12] though the quantity of rare metals used differs per car. Though Rare Earth metals are plentiful in the Earth's crust, only a few miners hold exclusivity to access those elements.[13]
• Possible increased particulate matter emissions from tires. This is sometimes caused by the fact that most electric cars have a heavy battery, which means the car's tires are subjected to more wear. The brake pads, however, can be used less frequently than in non-electric cars, if regenerative braking is available and may thus sometimes produce less particulate pollution than brakes in non-electric cars.[14][15] Also, some electric cars may have a combination of drum brakes and disc brakes, and drum brakes are known to cause less particulate emissions than disc brakes.
• pollution emitted in manufacturing, especially the increased amounts from producing batteries
• Passive pollution in certain cases; Electricity consumed for recharge is obtained from powerplants which release pollutants, thus even though during movement pollutants are not released the electricity utilised has already polluted. In case Nuclear power plants there are no visible pollutants but only nuclear waste which require costly storage,management etc.

Like all cars, electric cars give off particulate matter (PM) from road tyre and brake wear, and this contributes to respiratory disease.[16] In the UK alone non-tailpipe PM (from all types of vehicle not just electric) may be responsible for between 7,000 and 8,000 premature deaths a year.[16]

However, lower fueling, operation, and maintenance costs of EVs could induce the rebound effect, thereby releasing more particulates. In other words, cheaper driving costs serve to encourage more driving, thereby engendering more tire wear. (Other costs, such as congestion and the resulting incentive to pave more land in order to expand the road network, also arise.)

A solar energy charging station in North America

Electric cars emit less greenhouse gas over their lifetime than fossil fuel cars, except possibly in places with a very high proportion of coal-fired electricity, such as Serbia.[17][18][19] The size of the difference depends on distance driven as well as the source of the electricity, because the difference is mainly when the car is being driven rather than when it is being manufactured or recycled. For example, battery electric and hydrogen vehicles do not produce CO
2 emissions at all when driven, but only if their energy comes from renewable electricity[20] or low carbon sources like nuclear. Timing the charging process of electric vehicles according to the power generated by renewable power sources can increase the percentage of renewable energy in the electric grid.[21]

Even when the power is generated using fossil fuels, electric vehicles usually, compared to gasoline vehicles, show significant reductions in overall well-to-wheels global carbon emissions due to the highly carbon-intensive production in mining, pumping, refining, transportation and the efficiencies obtained with gasoline. This means that even if part of the energy used to run an electric car comes from fossil fuels, electric cars will still contribute to reduce CO
2 emissions, which is important since most countries' electricity is generated, at least in part, by burning fossil fuels.[22] Researchers in Germany have claimed that, while there is some technical superiority of electric propulsion compared with conventional technology, in many countries the effect of electrification of vehicles' fleet emissions will predominantly be due to regulation rather than technology.[23] The emissions of electrical grids can be expected to improve over time as more wind and solar generation is deployed.

Many, but not most or all countries are introducing CO
2 average emissions targets across all cars sold by a manufacturer, with financial penalties on manufacturers that fail to meet these targets. This has created an incentive for manufacturers, especially those selling many heavy or high-performance cars, to introduce electric cars and turbocharged cars as a means of reducing average fleet CO
2 emissions.[24]

Electric cars have several benefits over conventional internal combust engine automobiles, reduction of local air pollution, especially in cities, as they do not emit harmful tailpipe pollutants such as particulates (soot), volatile organic compounds, hydrocarbons, carbon monoxide, ozone, lead, and various oxides of nitrogen.[25][26][27] The clean air benefit may only be local because, depending on the source of the electricity used to recharge the batteries, air pollutant emissions may be shifted to the location of the generation plants.[28] This is referred to as the long tailpipe of electric vehicles. The amount of carbon dioxide emitted depends on the emission intensity of the power sources used to charge the vehicle, the efficiency of the said vehicle and the energy wasted in the charging process. For mains electricity the emission intensity varies significantly per country and within a particular country, and on the demand, the availability of renewable sources and the efficiency of the fossil fuel-based generation used at a given time.[29][30][31]

Charging a vehicle using renewable energy (e.g., wind power or solar panels) yields very low carbon footprint-only that to produce and install the generation system (see Energy Returned On Energy Invested.) Even on a fossil-fueled grid, it's quite feasible for a household with solar panels to produce enough energy to account for their electric car usage, thus (on average) cancelling out the emissions of charging the vehicle, whether or not the panel directly charges it.[32] Even when using exclusively grid electricity, introducing EVs comes with a major environmental benefits in most (EU) countries, except those relying on old coal fired power plants.[30] So for example the part of electricity, which is produced with renewable energy is (2014) in Norway 99 percent and in Germany 30 percent.

United States

Net electricity generation by energy source.[35] Coal is no longer the predominate source of electricity in the U.S. Chart does not take into account roof top solar.

According to a Union of Concerned Scientists study in 2018:[36]

"Based on data on power plant emissions released in February 2018, driving on electricity is cleaner than gasoline for most drivers in the US. Seventy-five percent of people now live in places where driving on electricity is cleaner than a 50 MPG gasoline car. And based on where people have already bought EVs, electric vehicles now have greenhouse gas emissions equal to an 80 MPG car, much lower than any gasoline-only car available."

Electric cars also have impacts arising from the manufacturing of the vehicle.[39][40] Since battery packs are heavy, manufacturers work to lighten the rest of the vehicle. As a result, electric car components contain many lightweight materials that require a lot of energy to produce and process, such as aluminium and carbon-fiber-reinforced polymers. Electric motors and batteries add to the energy of electric-car manufacture.[41] There are two kinds of motors used by electric cars: permanent magnet motors (like the one found in the Tesla Model 3), and induction motors (like the one found on the Tesla Model S). Induction motors do not use magnets, but permanent magnet motors do. The magnets found in permanent magnet motors used in electric vehicles contain rare-earth metals which are used to increase the power output of these motors. The mining and processing of metals such as lithium, copper, and nickel requires much energy and it can release toxic compounds. In developing countries with weak legislation and/or enforcement thereof, mineral exploitation can increase risks further. As such, the local population may be exposed to toxic substances through air and groundwater contamination. New battery technologies may be needed to resolve those problems. Li-ion batteries recycling is rarely done in developing and developed countries.[41] In fact, in 2017, only 5% of lithium-ion batteries were actually recycled in the EU.[42]

A 2018 report by ADAC (which looked at vehicles running on various fuels, including gas, diesel, hybrid and electricity) stated that "no powertrain has the best climate balance, and the electric car is not always particularly climate-friendly compared to the internal combustion engine car.[43][44] At its website, ADAC mentions that a big problem in Germany is the fact that much of the produced electricity comes from coal-fired power plants, and that electric cars are only climate-friendly when equipped with regeneration.[45]

Several reports have found that hybrid electric vehicles, plug-in hybrids and all-electric cars generate more carbon emissions during their production than current conventional vehicles but still have a lower overall carbon footprint over the full life cycle. The initial higher carbon footprint is due mainly to battery production.[30]

In 2017, a report made by IVL Swedish Environmental Research Institute also calculated that the CO
2 emissions of lithium-ion batteries (present in many electric cars today) are in the order of 150–200 kilos of carbon dioxide equivalents per kilowatt-hour battery.[46] Half of the CO
2 emissions (50%) comes from cell manufacturing, whereas mining and refining contributes only a small part of the CO
2 emissions. In practice, emissions in the order of 150–200 kilos of carbon dioxide equivalents per kilowatt-hour means that an electric car with a 100kWh battery will thus have emitted 15–20 tons of carbon dioxide even before the vehicle ignition is turned on. However, Popular Mechanics calculates that even if the 15–20 tons estimate is correct, it would only take 2.4 years of driving for the electric car with a 100kWh battery to recover the greenhouse emissions from the battery manufacturing.[47][48][49][50] Furthermore, two other studies suggest a 100kWh battery would generate about 6-6.4 tons of CO
2 emissions, so significantly less than what the IVL study claims.[51]

However, in December 2019, IVL Swedish Environmental Research Institute updated their 2017 study, reducing their estimate to 61-106 kg CO2-eq per kWh of battery capacity, with potential to go even lower.[52] The new study therefore shows carbon emissions from battery production are 2-3 times less intensive than previously reported, questioning studies that had taken the 2017 figure to prove EV were not better than ICE cars on life-cycle assessments.

Citing the 2019 study:

"The apparent decrease in total GWP [Global Warming Potential] from the 2017 report (150-200kg CO2-eq/kWh battery capacity) to 61-106kg CO2-eq/kWh battery capacity is partly due to that this report includes battery production with nearly fossil free electricity use which is the main reason for the decrease in the lowest value. The lowering of the high value is mainly due to improved efficiency in cell production. Another reason for a decrease is that the emissions from recycling are not included in the new range. They were about 15kg CO2-eq/kWh battery capacity in the 2017 report."

A 2020 study from Eindhoven University of Technology mentioned that the manufacturing emissions of batteries of new electric cars are much smaller than what was assumed in the IVL study (around 75 kg CO2/kwh) and that the lifespan of lithium batteries is also much longer than previously thought (at least 12 years with a mileage of 15000 km annually). As such, they are more ecological than gasoline-powered internal combustion cars.[53] [54]

Common technology for plug-in hybrids and electric cars is based on the lithium-ion battery and an electric motor which uses rare-earth elements. The demand for lithium and other specific elements (such as neodymium, boron and cobalt) required for the batteries and powertrain is expected to grow significantly due to the future sales increase of plug-in electric vehicles in the mid and long term.[55][56] While only 7 g (0.25 oz) of lithium carbonate equivalent (LCE) are required in a smartphone and 30 g (1.1 oz) in a tablet computer, electric vehicles and stationary energy storage systems for homes, businesses or industry use much more lithium in their batteries. As of 2016 a hybrid electric passenger car might use 5 kg (11 lb) of LCE, while one of Tesla's high performance electric cars could use as much as 80 kg (180 lb).[57]

Lithium

The Salar de Uyuni in Bolivia is one of the largest known lithium reserves in the world.[58][59]

The main deposits of lithium are found in China and throughout the Andes mountain chain in South America. In 2008 Chile was the leading lithium metal producer with almost 30%, followed by China, Argentina, and Australia.[56][60] Lithium recovered from brine, such as in Nevada[61][62] and Cornwall, is much more environmentally friendly.[63]

Nearly half the world's known reserves are located in Bolivia,[56][58] and according to the US Geological Survey, Bolivia's Salar de Uyuni desert has 5.4 million tons of lithium.[58][61] Other important reserves are located in Chile, China, and Brazil.[56][61] Since 2006 the Bolivian government have nationalized oil and gas projects and is keeping a tight control over mining its lithium reserves. Already the Japanese and South Korean governments, as well as companies from these two countries and France, have offered technical assistance to develop Bolivia's lithium reserves and are seeking to gain access to the lithium resources through a mining and industrialization model suitable to Bolivian interests.[58][64][65]

According to a 2011 study conducted at Lawrence Berkeley National Laboratory and the University of California Berkeley, the currently estimated reserve base of lithium should not be a limiting factor for large-scale battery production for electric vehicles, as the study estimated that on the order of 1 billion 40 kWh Li-based batteries (about 10 kg of lithium per car)[66] could be built with current reserves, as estimated by the U.S. Geological Survey.[67] Another 2011 study by researchers from the University of Michigan and Ford Motor Company found that there are sufficient lithium resources to support global demand until 2100, including the lithium required for the potential widespread use of hybrid electric, plug-in hybrid electric and battery electric vehicles. The study estimated global lithium reserves at 39 million tons, and total demand for lithium during the 90-year period analyzed at 12–20 million tons, depending on the scenarios regarding economic growth and recycling rates.[68]

A 2016 study by Bloomberg New Energy Finance (BNEF) found that availability of lithium and other finite materials used in the battery packs will not be a limiting factor for the adoption of electric vehicles. BNEF estimated that battery packs will require less than 1% of the known reserves of lithium, nickel, manganese, and copper through 2030, and 4% of the world's cobalt. After 2030, the study states that new battery chemistries will probably shift to other source materials, making packs lighter, smaller, and cheaper.[69]

According to a 2020 study balancing lithium supply and demand for the rest of the century needs good recycling systems, vehicle-to-grid integration, and lower lithium intensity of transportation.[70]

Rare-earth elements

China has 48% of the world's reserves of rare-earth elements, the United States has 13%, and Russia, Australia, and Canada have significant deposits. Until the 1980s, the U.S. led the world in rare-earth production, but since the mid-1990s China has controlled the world market for these elements. The mines in Bayan Obo near Baotou, Inner Mongolia, are currently the largest source of rare-earth metals and are 80% of China's production. In 2010 China accounted for 97% of the global production of 17 rare-earth elements.[71] Since 2006 the Chinese government has been imposing export quotas reducing supply at a rate of 5% to 10% a year.[72][73][74]

Prices of several rare-earth elements increased sharply by mid-2010 as China imposed a 40% export reduction, citing environmental concerns as the reason for the export restrictions. These quotas have been interpreted as an attempt to control the supply of rare-earths. However, the high prices have provided an incentive to begin or reactivate several rare-earth mining projects around the world, including the United States, Australia, Vietnam, and Kazakhstan.[73][74][75][76]

Evolution of global rare-earth oxides production by country (1950–2000)

In September 2010, China temporarily blocked all exports of rare-earths to Japan in the midst of a diplomatic dispute between the two countries. These minerals are used in hybrid cars and other products such wind turbines and guided missiles, thereby augmenting the worries about the dependence on Chinese rare-earth elements and the need for geographic diversity of supply.[74][77] A December 2010 report published by the US DoE found that the American economy vulnerable to rare-earth shortages and estimates that it could take 15 years to overcome dependence on Chinese supplies.[78][79] China raised export taxes for some rare-earths from 15 to 25%, and also extended taxes to exports of some rare-earth alloys that were not taxed before. The Chinese government also announced further reductions on its export quotas for the first months of 2011, which represent a 35% reduction in tonnage as compared to exports during the first half of 2010.[80]

In order to avoid its dependence on rare-earth minerals, Toyota Motor Corporation announced in January 2011 that it is developing an alternative motor for future hybrid and electric cars that does not need rare-earth materials. Toyota engineers in Japan and the U.S. are developing an induction motor that is lighter and more efficient than the magnet-type motor used in the Prius, which uses two rare-earths in its motor magnets. Other popular hybrids and plug-in electric cars in the market that use these rare-earth elements are the Nissan Leaf, the Chevrolet Volt and Honda Insight. For its second generation RAV4 EV due in 2012, Toyota is using an induction motor supplied by Tesla Motors that does not require rare-earth materials. The Tesla Roadster and the Tesla Model S use a similar motor.[81]

Battery electric vehicles have lower maintenance costs compared to internal combustion vehicles, since electronic systems break down much less often than the mechanical systems in conventional vehicles, and the fewer mechanical systems on board last longer due to the better use of the electric engine. Electric cars do not require oil changes and other routine maintenance checks.[82][28]

Internal combustion engines are relatively inefficient at converting on-board fuel energy to propulsion as most of the energy is wasted as heat, and the rest while the engine is idling. Electric motors, on the other hand, are more efficient at converting stored energy into driving a vehicle. Electric drive vehicles do not consume energy while at rest or coasting, and modern plug-in cars can capture and reuse as much as one fifth of the energy normally lost during braking through regenerative braking.[82][28] Typically, conventional gasoline engines effectively use only 15% of the fuel energy content to move the vehicle or to power accessories, and diesel engines can reach on-board efficiencies of 20%, while electric drive vehicles typically have on-board efficiencies of around 80%.[82]

Like ICE cars, as of 2021, many electric cars also contain lead–acid batteries. In some countries lead acid batteries are not recycled safely.[83][84]

• NEV's and electric velomobiles: low-capacity battery electric vehicles[85]
• Converting existing vehicle to electric (see environmental impact of manufacturing)
• Solar car: car powered by an electric motor, fed by a PV-panel; this does not have some of the disadvantages noted in this article
• Fuel cell car: car powered by an electric motor, fed by a fuel cell; this may not have some of the disadvantages noted in this article (if not foreseen with an additional battery)
• Induction motor: does not have permanent (rare-earth) magnets[86]
• Modal shift
• Phase-out of fossil fuel vehicles
• Plug-in hybrid electric car: is a hybrid electric vehicle whose battery can be recharged by plugging it into an external source of electric power, as well by its on-board engine and generator. While running in all-electric mode (EV mode), the plug-in hybrid operation is similar to an all-electric vehicle.
• Vehicles powered by advanced biofuels: carbon-neutral vehicles[87]
• Robotic disassembly of electric car batteries
• Downcycling of end-of-life e-automotive batteries