Electric Vehicle

Industrial Ecology

Environmental Impact of Electric Vehicle

MS Sustainability | Fall 2010 | BishoyTakla Dr. Wernick, PhD

Table of Contents Introduction ......................................................................................................................................3 History .............................................................................................................................................3

Economic and social concerns ........................................................................................................5

Environmental impact ......................................................................................................................7 Health impact of lead emission .....................................................................................................7 Leaded gasoline ............................................................................................................................8 Lead in batteries VS. Lead in gasoline ............................................................................................9 Lead in battery ..............................................................................................................................9 New technology in batteries ..........................................................................................................10 Lead-acidbattery ............................................................................................................................10 How we got our electricity? .........................................................................................................12 Recycling .......................................................................................................................................13 LCA of lead-acid battery ..............................................................................................................14 Conclusion ....................................................................................................................................15

Environmental Impact of Electric Vehicle Page 2 of 17

Introduction Electrical vehicles can be seen as the ultimate solution for the transportation and pollution problems. But are EVs really cleaner? Or they are simply shifting emissions from the tailpipe to the power generating plants? In order to find out the answer, the tools of industrial ecology are helpful inidentifying the criteria that an ideal EV must meet.

History Electric cars are not something new;they were invented in the late 1800’s2at the same time as the ICE cars.It was more comfortable and efficient, thus peoplepreferred it over the old steam car and the ICE cars because it didn’t need to be cranked and it was

Table 1 Automobile census in 1900 – New York , Boston and Chicago 1

type Steam Electric

easier to control. Itwas cast as productfor genteel society women; Henry Ford’s wife drove an electric car. The

Gasoline Carriage

number 1,170

Limiting factor Feedwater for boiler 800 Energy storage in battery 400 Size of gas tank 294,689 Endurance of horse

number of EVs in 1900 was double in the number than the Gasoline cars (Table1).

While EVs looked promising in different aspects it was largely an issue of perception. They were very efficient in terms of mileage. For exampleB.G.S ,France in 1899first electric car in the early 20th century was able to deliver 180 miles per charge in.

Also, common production units were capable of delivering 40 miles between charges and up to 100 miles a day under some circumstances. This was a lot more than the

Figure 1

industry average for steam cars, which had to stop between 10 and 15 miles for water and four times the distance between having to stop for fuel.

1 2

SAE Historical committee, a century of progress, Warrendale, PA 1997, 292pp http://inventors.about.com/library/weekly/aacarselectrica.htm

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The early gasoline cars also had to stop frequently for water for engine cooling and whileit wasn’t considered a disadvantage back then, gasoline cars had to stop within the range of 20 miles for minor repairs and adjustments3. This shows how well electric vehicles compared to industry averages in the early 20th century. They were also as fast as the gasoline cars were at that period of time and held the world land speed records between 1898 to 1902, beating out steam and gasoline-powered vehicles.

While the year 1912 witnessed the greatest number of electric on-road vehicles registered, , the number of sold electric cars was only a fraction of the number of ICE cars sold that same year. Cheap and readily available gasoline made ICE cars very competitive to electric vehicles, which operated on expensive electricity and a fragmented electrical generating industry and distribution network. The poor reliability on electricity compared to gasoline which was considered waste product of the petroleum industry at the turn of the 20th century, hugely caused the sales of electric vehicles to decline until General Motors stopped the manufacture of the EV1 in 2003 because of its huge manufacturing cost4,the cost of battery alone was $30,000. It was not feasible for GM to keep manufacturing EV1; therefore they brought them back in and destroyed them.5 (Figure 2) There was a problem that even Thomas Edison couldn’t 6

solve , and it has continually held back EV’s popularity and

Figure 2

growth, battery range couldn’t compete with the driving range of a full tank of gasoline.

Improving in the battery is the key to improving the EVs marketing and to make it more acceptable by regular users. Lead acid batteries were used in 1900 and are still used in some of the modern car; hence lead battery has the longest history of improvement among EVs batteries.

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http://webcache.googleusercontent.com/search?q=cache:RQiLmkBp9NQJ:www.econogics.com 4 http://www.autos.com/car-buying/why-gm-stopped-manufacture-of-their-ev-electric-car 5 http://www.autos.com/car-buying/why-gm-stopped-manufacture-of-their-ev-electric-car 6 http://www.wired.com/autopia/2010/06/henry-ford-thomas-edison-ev/

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Economic and Social concerns The initial investment in EVs is often higher than for a comparable gasoline car. The Nissan Leaf costs $30,0007, and the Chevrolet Volt costs $40,2808. On the other hand the price for similar size car is under $20,0009. But EVs’ price immediately drops by $7,500 with a federal subsidy10 for new buyers. Moreover EVs will save maintenance money because they never need oil changes, air filters, timing belts or emission tests, in addition to all the savings in usage phase since there no more money will be spentat the pump.

GM stated that customers who drive 40 miles per day will need about $1.19 worth of electricity every day11.Iif we were to use GM estimation for 10,000 miles, the EVs operating cost will work out to $2.98, compared with $1,200 for ICE car getting 25 mpg and gas at $3 per gallon. That’s 2.98 cents per mile for EV and about 12 cents for ICE cars, the different is 9.02

Table 2

cents per mile. For 100,000 EVs will save $9,020 in addition to the $7,500 federal subsidy, that’s total saving of 16,520 every 100,000 miles. Table 2 shows more comparisonsbetween the Dodge Caliber and Nissan Leaf. Studies expect the payback time to be only five years for EV. Considering the external costs, such as air and water pollution, land and soil degradation, non-renewable resources consumption and GHG generation, the full actual price should be adjusted to cover all these added costs. The environmental costs of transport have non-linear effects12, and the crucial issue becomes, nothow to measure but rather how to avoid reaching critical levels before the environmental cost becomes very expensive. Even though no one currently is paying for the emissions’ price, that doesn’t mean it is free of cost. According to the

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http://www.nissanusa.com/leaf-electric-car/index?dcp=ppn.39666654.&dcc=0.216878497#/leaf-electric-car/feature/pricing_information http://www.chevrolet.com/volt/?seo=goo_|_2008_Chevy_Retention_|_IMG_Chevy_Volt_|_Volt_HV_|_volt http://articles.moneycentral.msn.com/SavingandDebt/SaveonaCar/would-an-electric-car-save-money.aspx?page=2 10 IEA 2010 Technology Roadmaps: Electric and plug-in hybrid electric vehicles (EV/PHEV) 11 http://www.gm.com 12 Transport policy and the environment by David Banister

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“Ecology of Commerce” Paul Hawkins explains the difference between the cost and the price “companies aren’t required to pay for the damage to the environment”13.

ICE vehicles affect the environment in various ways and the most obvious one is in air quality. The U.S. emits nearly half the world’s automotive carbon dioxide14. In California; over half of the state’s pollution comes from ICE vehicles15. The release of greenhouse gases in the combustion of fossil fuels in the vehicles’ engines cause: 1- Acid rain (is occurring when water vapor reacts with sulfur and nitrogen dioxides, producing sulfuric and nitric acid16) Acid precipitation and other toxics can corrode building materials.

2- Photochemical smog (consisting of ozone and chemical compounds formed under the influence of sunlight from NOx and volatile organic compounds released in fossil fuel combustion17) The photochemical smog and pollutants emission such as CO2,CO, NO and, NO2 are directly affecting the lungs-respiratory system and increase the chances of cardio-vascular diseases. Statistic shows that U.S. air pollution deaths are equal to deaths from breast cancer and prostate cancer combined. are related to air pollution.18 From environmental standpoint, EV is More Efficient; it canconvert over 90% of electrical power supplied into motion, while ICE can only convert 25% into motion19 (figure 3).

On a full life cycle basis,electric vehicles manage about 34% efficiency versus only 14% for gasoline vehicles including power plants and oil wells20. Hence, experts predict decrease inthe production of ICE and increase of the production of EVs by 2020(figure 4). The mass production of EVs will decrease the initial cost.

Figure 3 13

Figure 4

Ecology of Commerce, chapter 5 http://www.ens-newswire.com/ens/jun2006/2006-06-28-03.html 15 http://www.electroauto.com/info/pollmyth.shtml 16 http://www.ausetute.com.au/acidrain.html 17 http://www.lenntech.com/faq-air-pollution.htm 18 http://www.earth-policy.org/index.php?/plan_b_updates/2002/update17 19 http://www.fueleconomy.gov/feg/atv.shtml 20 http://truecostblog.com/2009/01/04/electric-vs-gasoline/ 14

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The batteries’ range is another concern raised by potential electric buyers. Currently US has only 500 public charging stations a condition that raises the fear of running out of power far from charging station or far from home. But the average American commute distance is 40 miles a day (Figure 4), which can be managed by single charge.However Obama’s administration has made major investments in clean-energy vehicles, including $2.4 billion to establish EV battery plants, and to open20,500 charging

Figure 5 US Department of Transportation, Bureau of Transportation Statistics, Omnibus Household Survey

locations on the grid by 201221.The battery range depends onvaries factors like weather condition, speed, road conditions, and air conditioning or heat use. Once the automobile market movestowards EVs, we will witness more infrastructures for EVs as we have for ICE cars, less gas station and morecharting stations.

Environmental Impact Health impact of Lead emission Most people are exposed to a small amount of lead through air, drinking water, soil, dust, food or other consumer products.The usage of lead increased after the industrial revolution and during the 1920’s with the usage of the leaded gasoline,but in the 1970’s some studies revealed the harmful impacts of the high lead level in blood. The high exposure of lead for short term can cause vomiting, diarrhea, convulsions, coma or even death22, and the long exposure is very harmful and can case damage to the brain and the nerve.

Figure 6

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http://www.infrastructurist.com/page/3/

http://www.hc-sc.gc.ca/hl-vs/iyh-vsv/environ/lead-plomb-eng.php

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Therefore the US Center for Disease Control reduced its definition of dangerous leadconcentrations in the blood from 25 to 10 micrograms per deciliter23, and the US National Research Council states this fact as “the central and the peripheral nervous system of both children and adults are demonstrably affected by lead exposures formally thought to be well within the safe range”24. Figure 6 compares the lead level in blood between 1983 and 1994 according to the National Health and Nutrition Examination Survey. In 1983 only 12% of the children had 10 or less mcg/dL lead in their blood, in another word only 12% of the children had the acceptable lead blood level, whereas the time of NHANES III , the percentage has grown to 91%25.

Leaded gasoline Lead was used in gasoline in the 1920’s, to raise its octane in order to improve the gasoline combustion, and to provide lubrication that prevented friction in the engine.Leaded gasoline was the main source of the lead air emission26consequently, leaded gasoline was banded in the United States in 199527, when more advanced addictive were invented. Figure7shows the first major stepwas taken in 1970’s to reduce the lead percentage; however other countries still using leaded gasoline. According to the International Fuel Quality Center28 there are 39 countries are still using leaded gasoline in the world. The International Fuel QualityCenter believes that lead will be completely phased out in the next decade29.

Figure 7 23

http://www.ecy.wa.gov/programs/hwtr/demodebris/pages2/lbloodtest.html http://www.nap.edu/openbook.php?record_id=2232&page=31 25 http://www.cdc.gov/mmwr/preview/mmwrhtml/mm4950a3.htm 26 http://yosemite.epa.gov/R10/airpage.nsf/webpage/Leaded+Gas+Phaseout 27 Previous source 28 Overview of leaded gasoline and sulfur levels in gasoline and diesel, November 14, 2002 29 http://www.un.org/esa/gite/cleanfuels/ifqc-globaloverview.pdf 24

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Lead in batteriesVS. Lead in gasoline Industrial ecology studies industrialized activities as the flow of material from and into the environmental system. From an industrial ecology point of view the lead in gasoline addictive is considered dissipative use30,because it exhausts to the air from the car’s tailpipe after the gasoline is burned, the lead dissolves in the air components and later deposited on soil and crops. The harm is not only by breathing the polluted air but also by eating the ingesting and polluted crops. However, the solution to phase-out the lead addictive in gasoline in the rest of the world is easier to be achieved, especially by looking at to the current practices ofbanding lead additives. On the other hand the lead in batteries is recyclable use31. Because all the lead remain in the battery when the battery undergoes its normal cycle of charge and discharge.

Lead in battery Lead batteries are dominating the US lead industry more than 80% of lead produced in the United States is used for lead-acid batteries32;figure 8shows the average data for US lead industry in 1993 in thousand metric tons. Lead that enters the system from

Figure 8

mining and importing are more than what leaves the system via disposal and exporting. Raw lead material (left bottom) from mining and imported battery enter the industry, some lead stayed in the system and gets recycled (the middle top). In 1990 the global lead production was 5.9 million metric tons and it has 2.6 million metric tons of recycled lead. At the end of the batteries’ life cycle some of these batteries end up in land fill (bottom right), where there’s a chance that the lead will move into the groundwater or the surface water.

30

journal of Industrial ecology by Robert Socolow Previous source 32 http://www.leadacidbatteryinfo.org/environment.htm 31

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Regarding the health impact from lead used in batteries, figure 8.1 shows the decreasing in average lead level in bloodand at the same time increasing of lead used in the battery industry, simply because the used lead in batteries remains in the battery after its life cycle.

Treating the lead in EV’s batteries and lead additives in gasoline on the same footing is misleading. The lead in gasoline is dissipative and the emission can’t be bounded or recycled, in contrast the lead in the batteries is recyclable and can be used or at least can be disposed under environmental

Figure 8.1

control New technology in batteries Better batteries are crucial to the improvement and eventual success of the electric vehicles (figure 9). To understand the difference between batteries, industrial ecology and life cycle analysis are needed to break the battery into its simplest form of material and energy. Iwill look at the life cycle analysisof the lead-acid battery and

Figure 9

studyits energy consumptionand its CO2 emission duringthe production, manufacturing,usage and recycling stages.

Lead Acid Batteries The basic chemical components of batteries are two active materials and an electrolyte, during discharge these components react to form new chemical compounds,

Figure 10

releasing energy which is available as electricity for external use.33 Most of the active materials in battery are nonstandard automobile material, however a significant fraction of the battery mass is standard material such as steel and polypropylene used for casings, connectors and separators.

The leadacid battery was invented in 1859; it is consisting of a Leaddioxide (cathode), a sponge metallic Lead anode and a Sulfuric acid solution electrolyte (figure 10)34. This heavy 33

Prospects for electric cars by William Hamilton

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metal element makes them toxic and improper disposal can be hazardous to the environment35.

During discharge, the lead dioxide (positive plate) and lead (negative plate) react with the sulfuric acid (electrolyte) to create energy, lead sulfate and water (as shown in the discharging equation). During charging, the cycle is reversed: the lead sulfate and water are electrochemically converted to sulfuric acid, lead and lead oxide by an external electrical charging source. 36 Discharge Pb02 + Pb + 2H2SO4 +plt

----------> 2PbSO4 + H2O + 2E

-plt electrolyte <----------

+/-plt electrolyte

Charge

The Lead-acid battery has some advantages such as; its low cost, its reliability (Over 140 years of development), it also can deliver very high currents, it has anindefinite shelf life if stored without electrolyte and it has wide range of sizes and capacities available. On the other hand, it has some disadvantages such as it is heavy weight and it can be overheated during charging.

Production and Manufacture

Table 3

About 76% of the production of energy goes to the lead production and most of the rest to the polypropylene case37 and the percentage can be lowered to 17% of the vetchesâ&#x20AC;&#x2122; total production energy if recycled leadis Table 4 34

http://www.circuit-projects.com/battery/12v-lead-acid-battery-discharge-indicator.html http://www.mpoweruk.com/leadacid.htm 36 http://www.mpoweruk.com/leadacid.htm 37 http://www.transportation.anl.gov/pdfs/B/239.pdf 35

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usedinstead. As shown in table 3 lead is the most used material followed by water and sulfuric acid, which form the electrolyte,the secondary battery in the table assumed to be made from some recycled material.

The process starts with the production of the grids, production of lead oxide, paste production and pasting, then drying following by curing and formation.

During the manufacturing process toxinsare emitted from physical and chemical processes, in addition the emission of the combustion fuel used to transport the material.

Usage phase - How we got our electricity?

The greatest environmental advantage of EVs is their low emissions; however during the life time of the battery, it uses electricity which is generated from power plants that emitpollutants. The question that should be asked is that how much are EVs net saving of emissions? We can determine this after calculating its production and manufacturing energy’s emission and by considering the lifetime usage electricity’s emissions.

Critics nickname the EVs “elsewhere emission vehicles” because they transfer emissions from the tailpipe to the power planet’s smokestack, and they proclaim that more EVs will significantly increase GHG.In contrast The World Resources Institute states that EVs “recharging from coal-fired plants will reduce CO2 emissions in USA from 17 to 22 percent.”38 Even though US power planets generate 45% of their electricity from coal, the emissions associated with charging EVs are very low.39 Usage of electricity generated from a variety of fuels and renewable resources is an advantages of EVs’, because all what we need to achieve is increasing these mixes and increase the share of the

Figure 11

renewable energy. The overall mix of power plants in the U.S. in 2010 is 45% coal and 24% percent natural gas. The rest 31% include nuclear power and renewable energy sources (Figure 11).

38 39

James J. MacKenzie, The Keys to the Car, (World Resources Institute, Baltimore, Maryland, May 1994) http://www.evdl.org/docs/powerplant.pdf

Figure 12

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In the ICE cars, the production and disposal represent only 20 %t of a car’s environmental impact and the other 80 % is caused by burning fuel during the usage phase.On the other hands EVs has less than 30% of its impact in the usage phase because it get its electricity from power plants that emit emissions in less crowded areas. By centralizing electric power plants can achieve fewer emissions per vehicle mile than ICE. In fact, it is possible that all EVs can be charged from solar energy, by using the new Korean Plug-N-Go (figure 12).40The EV Plug-N-Go was showcased at the Clean Tech Open in Korea, this solar-powered platform is ideal to charge EVs from natural energy and achieve a zero emission stage. According to studies by the Los Angeles Department of Water and Power, EVs are much cleaner in the usage phase than ICE cars41. The electricity generation process produces less than 100 pounds of pollutants for EVs compared to 3000 pounds for ICE vehicles42(table 5).

Table 5. Pounds of Emissions Produced per 100,000 Miles43 CO ROG NOx Engine 2574 262 172 Gasoline 216 73 246 Diesel 9 5 61 Electric

Total 3008 lbs 835 lbs 75 lbs

Recycling The battery represents a significant percentage of the vehicle mass, (20% to 40%), the recycling impact is very important because the batteries’ life time is shorter than the vehicles’ life time, it will need to be replaced every 3-5 years44. The data are incomplete because the recycling of all the materials is not developed yet; lead and the polypropylene cases are mostly recyclable. Electricity consumption in recycle is 0.875 MJ/kg (table 6).

Table 6 http://inhabitat.com/plug-n-go-ev-charging-station-showcased-at-green-energy-expo/ http://www.afdc.energy.gov/afdc/laws/law/CA/6142 42 http://www.electroauto.com/info/pollmyth.shtml 43 Steve McCrea, Why Wait for Detroit, (South Florida Electric Vehicle Auto Association, 1992) 44 http://www.freewebs.com/worldwideevsource/evparts.htm 40 41

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More than 95% of battery lead is recycled45, Randy Hart, President of BCI, said “The lead--acid battery recycling structure has been proven to be efficient and highly successful, and no other battery chemistry comes near the recycling rate of lead lead-acid batteries … It proves ves that a workable infrastructure helps boost

Figure 13

consumers’ participation in recycling.” (Figure 13).

Lead-acid LCA Production and recycling of EV batteries may be having significant environmental consequences. Therefore all process must receive careful attention to minimize possible impacts.

The total energy needed for manufacture and recycle is shown in Table 7, but as shown in Figure 14 the use of battery has 85% ofits LCA energy. The solution to reduce the energy consumption tion in the use time is not only to improve the batteries’ efficiency. If the battery had an energy efficiency of 95%, the usage consumption energy will be reduced from 85% to 80%46. Therefore reducing losses in the power plants and improve the charging efficiency iciency will have a significant impact. The car manufacture, the power supply industry, charger manufacture as well as the battery industry should join forces in order to improve the EV’s environmental impact and to make it operates efficiently and reliably

Figure 14

45

http://www.leadacidbatteryinfo.org/environment.htm 46

Life cycle assessment of five batteries by MichailR MichailRantik Page 14 of 17

Table 7 Electricity Oil LPG Heat

Manufacture 4.793 0.102 0.137 1.671

Recycle .075 1.95 -1.568

Table 6. summary of lead-acid battery47 Lead on fiberglass Electrode material mesh Sulfuric acid Electrolyte 50 Wh/kg E density 500 kg Mass for 35 kWh 11.7 (106 Btu) E to make 2.5 (106 Btu) E to recycle Lead particulates Significant emissions Short battery life, comments existing recycling infrastructure

Conclusion The ultimate viability of EVs as the main personal vehicle modes is the next step that needs to be taken. The lack of connivances, such as the shortage in the infrastructure, the charging station, and the long range batteries, held back EVs from reaching mass production.

The gasoline industry also has a role in slowing down the improvement. The government can support EVs by investing in advanced researches to improve the batteries range and weight, while considering lead emission in the battery manufacturing and battery recycling,in order to reduce the lead pollution from batteries. Thomas J. Watson once said â&#x20AC;&#x153;It is better to aim at perfection and miss, than to aim at imperfection and hit itâ&#x20AC;? and I think US government should aim high to achieve a total change from ICE into Electric Vehicles. GM planned to generate 14 new model of hybrid car by 201248.The hybrid cars can be seen as the transaction stage from ICE to total eclectic, according to the suggested commercial pathway (figure 15). We are half way far to the EVs.

Figure 15 47 48

Impacts of EV Battery Production and Recycling by Linda Gaines and Margaret Singh http://wot.motortrend.com/6525361/green/gm-promises-14-hybrids-by-2012-we-id-the-potential-line-up/index.html

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