Environment

Just how environmentally friendly are electric vehicles?

Just how environmentally friendly are electric vehicles like the Tesla Roadster?
Just how environmentally friendly are electric vehicles like the Tesla Roadster?

Because they produce no exhaust gases in operation electric vehicles (EVs) are seen as the eco-friendly alternative to conventional gas-fueled cars. While zero-local emissions is clearly a big plus, other factors contributing to the overall environmental impact of EVs are often overlooked – namely the manufacture, usage and disposal of the batteries used to store the electrical energy and the sources of power used to charge them. Now, for the first time, a team of scientists from the Swiss Federal Laboratories for Materials Testing and Research (or EMPA) have made a detailed life cycle assessment or ecobalance of the type of lithium-ion batteries most frequently used in EVs, to see if they really are as environmentally friendly as their manufacturers would have us believe.

Fuel source is the key

The investigation shows that, if the power used to charge the battery is not derived from purely hydroelectric sources, then it is primarily the operation of the EV that has an environmental impact, exactly as is the case with conventionally fueled vehicles. In other words, the size of the environmental footprint depends on which sources of power are used to “fuel” the EV. Contrary to initial expectations that the manufacture of the batteries could negate the advantages of electric drive vehicles, the Li-ion battery itself was actually found to have a limited effect.The team calculated the ecological footprints of electric cars fitted with Li-ion batteries, taking into account factors such as those associated with the production of individual parts, the operation of the vehicle during its lifetime, all the way through to the scrapping of the vehicles and the disposal of the remains. The electric vehicles evaluated were equivalent in size and performance to a VW Golf, and the power used to charge the batteries was assumed to be derived from sources representing an average European electricity mix – that is, a mixture of atomic, coal-fired and hydroelectric power stations.

For comparison the team used a new petrol-engined car, meeting the Euro 5 emission regulations. It consumes on average 5.2 liters (1.37 U.S. gallons) per 100km (62 miles) when put through the new European Driving Cycle (NEDC), a value significantly lower than the European average. In this respect, therefore, the conventional vehicle belongs to the best of its class on the market.

Results

The study shows that the electric car’s Li-ion battery drive is in fact only a moderate environmental burden. At most only 15 per cent of the total burden can be ascribed to the battery (including its manufacture, maintenance and disposal). Half of this figure, that is about 7.5 per cent of the total environmental burden, occurs during the refining and manufacture of the battery’s raw materials, copper and aluminum. The production of the lithium, in the other hand, is responsible for only 2.3 per cent of the total.“Lithium-ion rechargeable batteries are not as bad as previously assumed,” according to Dominic Notter, coauthor of the study which has just been published in the scientific journal Environmental Science & Technology.

The outlook is not as rosy when one looks at the operation of an electric vehicle over an expected lifetime of 150,000 kilometers (93,205 miles). The greatest ecological impact is caused by the regular recharging of the battery, that is, the “fuel” of the e-car. Topping-up with electricity sourced from a mixture of atomic, coal-fired and hydroelectric power stations, as is usual in Europe, results in three times as much pollution as from the Li-ion battery alone. If the electricity is generated exclusively by coal-fired power stations, the ecobalance worsens by another 13 per cent. If, on the other hand, the power is purely hydroelectric, then this figure improves by no less than 40 per cent.

The EMPA team concluded that a petrol-engined car must consume between three and four liters per 100km (or about 70mpg) in order to be as environmentally friendly as the electric car studied, powered with Li-ion batteries and charged with a typical European electricity mix.

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27 comments
dreamer.redeemer
The fundamental problem that isn\'t being addressed is using ~3000 pounds of steel to transport ~300 pounds of human. Meanwhile, my electric bicycle kit comes in tomorrow... expected fuel efficiency equivalent? ~960 mpg. Not to mention the ancillary benefits of cleaner air, increased physical fitness/health, and money saved from licensing/registration/fuel.
4Freedom
I\'m not sure why they do not mention other renewable sources such as wind and solar, only specifying \"hydroelectric sources\". Maybe that\'s all they have to work with in Europe? (I doubt it.) It seems odd that they wouldn\'t mention wind and solar as equal alternatives.
Raum Bances
It is an interesting study but there are some things wrong or exaggerated.
Does the average European really toss away their car after 93,000 miles? My current car has over 140,000 and therefore will be recycled at half the rate they are calculating. (by the time I get rid of it).
Also, in the time they are calculating, the EU is scheduled to increase renewable sources by about 25% of now. This will change the the math year to year. That does not appear to be the case in the study.
The big picture is also missing here. When we run out of fossil fuels, or run low enough that the cost sky rockets, it won\'t matter how efficient a standard fuel powered car is. There will be nothing to put in the tank.
PrometheusGoneWild.com
This whole article treats the source of the electricity to charge the car as static. Like it will never change. This is foolish. Once we have a significant amount of cars that are electric, governmental policy can cause what power sources we have to change over time to renewable forms. Renewable sources continue to gain ground on efficiency and cost. At some point in the next decade or so we may be able to make the choice to stop burning coal. I am no tree hugger, but telling the oil companies and coal companies to stick it is a worthy goal. Dennis www.PrometheusGoneWild.com
jerryd
I\'d like to look at the way they did this as EV\'s only use 33-12% of the energy/mile of an ICE, depending on electric source.
Plus I\'d bet they didn\'t include gasoline\'s full cost to pump, refine which is at best 60% eff plus the cost of importing, protecting the oil.
Plus by the time any real numbers of EV\'s are online, power will have far less coal and more RE. Now add the fact that most EV\'s will be charged off peak when the energy is going to waste from nukes, some RE and running EV\'s is far better than running ICE\'s on oil.
Add that one can make one\'s own fuel for EV\'s by solar, wind or biomass/CHP units, and eff increases, impacts drops far more.
napaeric
It is interesting that the battery has little impact on the environment. The typical European mix for electricity does not seem to take into account the rapidly increasing use of PV, wind, geothermal and tidal. Since coal plants are becoming a smaller percentage and renewable is rapidly increasing in the percentage mix it would seem to indicate that the future electricity will become cleaner. I can easily predict that fossil fuels will only increase there ability to pollute. Gulf of Mexico Spill is of course the latest stain on the fossil fuel tapestry.
PizzaEater
There was a group a few years ago that determined all the costs for building, operating and disposing of a hybrid vehicle, compared to a conventional vehicle. The environmental burden of the hybrids such as a Prius exceeded that of a Hummer H3. Here is a summary of that report here: http://www.hybridcars.com/environment-stories/dust-to-dust-energy-costs.html. Or find all the reports here: http://www.cnwmr.com/nss-folder/automotiveenergy/ Look at the Dust to Dust report. The main reason a Hummer is less burdensome to the environment is that the engineering is simple and several decades old. It\'s a hunk of steel with plastic thrown inside. Over time the engineering cost for hybrids will be diluted by millions of vehicles. Another downfall for the hybrid is the expected lifetime of just 100,000 miles.
jmatus
This is all well and good, until demand for electricity to charge all the new electric cars surpasses supply, and new fossil fueled power plants are built to makeup the short fall.
kelvint63
Hybrids are made to be a temporary solution to ease the transition from gas to no-gas. Going cold-turkey from oil is not a good idea when we realize how entrenched oil is in our modern lives; look around, it has an effect on everything; just because we don't notice it doesn't mean the connections are not there. The biggest tentacle is the TAX added to every gallon of gas. You know that the government doesn't like to give up a tax until it has a replacement in place. LOL
Colter Cederlof
Hopefully they also took into account that car engines are horribly inefficient when compared to using the exact same fuel at a power plant. By having the electric cars pull the power from the grid we can at least shift the fuel consumption to the more efficient means of electrical production.