How Green Are Electric Cars? Depends on Where You Plug In

[surfingslovak]

It’s a lot like one of those math problems that gave you fits in sixth grade: a salesman leaves home in Denver and drives his electric car to a meeting in Boulder. At the same time, a physicist driving the same model electric car sets out from her loft in Los Angeles, heading to an appointment near Anaheim.

The test question: are their carbon footprints also equal?

The answer may be a surprise. According to a report that the Union of Concerned Scientists plans to release on Monday, there would be a considerable difference in the amount of greenhouse gases — primarily carbon dioxide — that result from charging the cars’ battery packs. By trapping heat, greenhouse gases contribute to climate change.

To prevent the worst consequences of global warming, the report concludes, the automotive industry must deliver viable alternatives to the oil-fueled internal-combustion engine — i.e., vehicles boasting zero or near-zero emissions.

http://nyti.ms/howgreennytimes2" onclick="window.open(this.href);return false;

And on a related note, Tom Moloughney recommended a DOE site, which helps determine the local energy mix by ZIP code. Not only that, it provides estimates for fuel costs and CO2 emissions for all types of vehicles, including BEVs.

http://bit.ly/bevco2" onclick="window.open(this.href);return false;

 

[keydiver]

Hmmmm..why does that site say 26% of my electricity comes from coal, when FPL claims they only generate 7% of their power from coal? Maybe they are buying a lot from outside their system? I'll have to ask my friends that work there. Not that it really matters though, as I charge almost 100% from my solar.
Nice site though!

 

[BRBarian]

The benefits of the removal of local pollution seems to be always neglected in these articles.

While global CO2 pollution is important, it's the local pollution that's making us sick and killing the elderly.

 

[edatoakrun]

The article makes no reference to a very pertinent fact, that I hope the actual report will.

If you charge your BEV at night, you are probably responsible for much smaller, emissions per kWh, than the regional grid 24 hour average.

On the west coast, a very large proportion of off-peak electricity production is made up of Nuclear, hydro, and "renewables" with very low CO2 output.

Conversely, it is possible, if utilities use cheap, inefficient, coal plants, for base-load demand, off-peak power may actually be producing more CO2 pollution by charging off-peak, than by daytime charging. I doubt this is the case anywhere in the US, over the entire regional grid, very often, though.

But in almost every case, BEVs will produce lower CO2 emissions per mile, every year in the future, as grid efficiency and less CO2 intensive fossil fuel power production increases.

An ICEV will produce higher CO2 and other GHG emissions each year, even as it gets the same mpg, since more and more gasoline is produced by more polluting tar sands and shale oil sources, every year.

 

[DesertDenizen]

Hmmmm..why does that site say 26% of my electricity comes from coal, when FPL claims they only generate 7% of their power from coal? Maybe they are buying a lot from outside their system? I'll have to ask my friends that work there. Not that it really matters though, as I charge almost 100% from my solar.
Nice site though!

I am with keydiver, charge using my solar, that is as green as it gets.

 

[DaveEV]

Anyone able to find the actual UCS report that the NYT article is quoting?

 

[surfingslovak]

Anyone able to find the actual UCS report that the NYT article is quoting?

I believe that it's supposed to be released tomorrow. I would also watch for a press release regarding lithium-air batteries.

 

[planet4ever]

And on a related note, Tom Moloughney recommended a DOE site, which helps determine the local energy mix by ZIP code. Not only that, it provides estimates for fuel costs and CO2 emissions for all types of vehicles, including BEVs.

http://bit.ly/bevco2" onclick="window.open(this.href);return false;

The DOE uses a top-level domain name assigned to Libya :?: Doesn't sound very likely to me. I'd be more likely to believe it's someone harvesting URLs by zip code.

Ray

 

[808pv]

Like a lot of similar assessments, the article neglects to mention the emissions needed to refine and transport the gasoline used by ICE cars. If they're going to measure upstream emissions, they should do so for both types of vehicle, or the comparisons are invalid. Can't tell yet if this is a weakness of the article or the study.

 

[Smidge204]

The DOE uses a top-level domain name assigned to Libya :?: Doesn't sound very likely to me. I'd be more likely to believe it's someone harvesting URLs by zip code.

Uh... bit.ly is a popular URL shortening service, especially with Twitter users since it saves on characters. The actual URL, to which you are redirected, is:

http://www.afdc.energy.gov/afdc/vehicles/electric_emissions.php

Your skepticism and concern for internet privacy/security is laudable, but your researching skills need some work. (P.S. your IP is probably a better indication of your geographical location than a ZIP code, especially since you can type a ZIP code that isn't yours easier than you can spoof your IP/use a proxy. Farming ZIP codes is less than useless IMHO.)

Edit: And this morning I had a link to this in my email: Coal-fired generation to decline in U.S. - Electric cars gettin' cleaner by the day!
=Smidge=

 

[surfingslovak]

And on a related note, Tom Moloughney recommended a DOE site, which helps determine the local energy mix by ZIP code. Not only that, it provides estimates for fuel costs and CO2 emissions for all types of vehicles, including BEVs.

http://bit.ly/bevco2" onclick="window.open(this.href);return false;

The DOE uses a top-level domain name assigned to Libya :?: Doesn't sound very likely to me. I'd be more likely to believe it's someone harvesting URLs by zip code.

Ray, I've created those URLs using bit.ly, a link shortening service. This comes in handy when sharing them on Facebook and Twitter. I used to use tinyurl.com before, but bit.ly has a shorter domain name, and they provide additional anonymized usage data. This helps to determine, which links were popular, and which were not, and if they have been viewed by users in a foreign country. Like Japan or Germany for example ;-)


Click to open

 

[DaveEV]

Anyone able to find the actual UCS report that the NYT article is quoting?

I believe that it's supposed to be released tomorrow. I would also watch for a press release regarding lithium-air batteries.

Report is out:
http://www.ucsusa.org/clean_vehicles/technologies_and_fuels/hybrid_fuelcell_and_electric_vehicles/emissions-and-charging-costs-electric-cars.html" onclick="window.open(this.href);return false;

Now where is that press release regarding lithium-air batteries?

 

[charlie1300]

I've given up on articles about "carbon footprint" of what ever. It seems to me that the author(s) use whatever numbers they choose to make the point they are inclined to support. Given the fact that our entire economy is fossil fuel based, you can follow the CO2 footprint back thru the various input threads to any economic activity as far as you want, racking up more CO2 inputs as you go along. So the winner or loser is determined by the authors decision on where to stop back tracking.
I advocate a common sense approach - beef has larger foot print than chicken, which is larger grains. Pretty obvious - you need to raise the grains to feed the chicken, and the cow needs more grains per pound of meat because it is a larger animal that matures slower.
Same with BEV vs ICE - gasoline engines in cars are much less efficent than power plant boilers, so the BEV produces less CO2, even if the power plant is coal fired. Unless you are in West Virginia, at least some of the power generation is cleaner than coal, and some folk use their own solar, or(like me) purchase all renewable energy from their utility.

Of course you could argue that my electricty is no completely carbon free because the utility maintains the lines with gasoline powered trucks, or that the linemen drive to work in ICEs, or that they go home after work and eat a big steak instead of rice and beans....... You get the drift.

So my point is that if the difference isn't pretty obvious after understanding the basics of the process of production, and you have to add up estimated CO2 inputs to compare, then there probably isn't much difference.

 

[Reddy]

Hmmmm..why does that site say 26% of my electricity comes from coal, when FPL claims they only generate 7% of their power from coal? Maybe they are buying a lot from outside their system? I'll have to ask my friends that work there. Not that it really matters though, as I charge almost 100% from my solar.
Nice site though!

I tried several zips in WA and got the same thing. Sorry, this data must be old, binned over too large an area, or just plain wrong. I can't believe we are at 32% coal. How can that be when we have 25 GW hydro capacity (12 GW current production), and only 6-8 GW use? :? What, are will spilling water so and using coal instead? I'd believe the info provided by your local utility more than the website.

Reddy

 

[lpickup]

I wasn't sure where to post this, but this topic seems somewhat related...

Just got back from a visit to a college visit for my son in Kentucky coal country. I'm not sure how far away we were from the mine, but there was a double set of train tracks about 100 yards behind our hotel, and we were kept up all night by trains running back and forth full of coal (and empty ones heading back to the mine). It was just mind boggling how much coal was headed out to be burned to attempt to satisfy our country's immense need for power.

I buy enough green power offsets to power my LEAF each month...now I'm going to see about adding more to cover the rest of my electric needs so those poor people in that town can get some damn sleep at night!

I think it would be a good idea for everyone to spend a sleepless night at that hotel!

 

[lukati]

To most accurately compare electric and gasoline vehicles, the emissions from producing the fuel as well as from consuming it must be taken into account. For gasoline vehicles, this means including emissions not only from propelling the car—i.e., by combusting the fuel in the engine—but also the emissions associated with extracting petroleum, refining it, and delivering it to the vehicle. For EVs, no tailpipe emissions occur from consuming electricity to propel the vehicle. However, as described above, there are emissions from producing the electricity. Thus in comparing EVs with gasoline vehicles we include the “wells-to-wheels” emissions, which account for the full fuel cycle.

It looks like the report wants to compare apples to apples, but I couldn't see any evidence that it actually addresses the "wells-to-wheels" question for gasoline powered cars. Did I miss it?

 

[surfingslovak]

It looks like the report wants to compare apples to apples, but I couldn't see any evidence that it actually addresses the "wells-to-wheels" question for gasoline powered cars. Did I miss it?

Yes, the report specifically mentioned "wells-to-wheels", and I could not find any evidence of it either.

 

[davewill]

Ray, I've created those URLs using bit.ly, a link shortening service. ...

BTW, I and many others skip over links that have been anonymized in this fashion. I like to see where I'm going before I go there.

 

[padamson1]

Yes, the report specifically mentioned "wells-ts to compare apples to apples, but I couldn't see any evidence that it actually addresses the "wells-to-wheels" question for gasoline to-wheels", and I could not find any evidence of it either.

Unfortunately many reports (such as http://web.mit.edu/evt/summary_wtw.pdf) don't discuss the details of the analysis (does it include fuel used to transport from well to power plant/refinery, CO2 used to refine, etc). There are several Well-to-Wheels studies if you Google it. The ones that give details on their analysis exclude some data that I believe should have been included. The ones that do not give details seem to give EV's less credit than makes sense. There are some that show that EV's are worse with specific pollution like NO2, Well-to-Pump (WTP) because of coal fired plants, but they don't seem to reflect BEVs are most commonly charged at night (which means the energy as lower pollution due to several factors). Here is a nice critique of the Argonne Wells-to-Wheels (WTW) study, https://sites.google.com/site/nwpri...eenhouse-gas-emissions-from-electric-vehicles showing that actual driving data differs from Argonne's estimated driving efficiency yielding very different conclusions.

Without such details I am inclined to agree with charlie1300 since authors tend to favor data to get the result they want. As he says, it defies common sense that a BEV doesn't pollute less WTW:

- Well to pump: (pump being the EVSE) BEV's should win b/c the source fuel is going a shorter distance before it is converted into gasoline/electricity and refining is less efficient than conversion of coal/gas/water/uranium to electricity. There is transmission loss, but that's still got to be less than trucking it from the refinery to the gas station. Sure coal fired plants are nasty, but they are getting better and are quickly being replaced by cleaner NG.
- Pump to tank: ICE wins b/c of inverter loss ~15% vs the tiny amount electricity to pump gas
- Tank to Wheels: EV's win big time.

 

[GRA]

Yes, the report specifically mentioned "wells-ts to compare apples to apples, but I couldn't see any evidence that it actually addresses the "wells-to-wheels" question for gasoline to-wheels", and I could not find any evidence of it either.

Unfortunately many reports (such as http://web.mit.edu/evt/summary_wtw.pdf) don't discuss the details of the analysis (does it include fuel used to transport from well to power plant/refinery, CO2 used to refine, etc). There are several Well-to-Wheels studies if you Google it. The ones that give details on their analysis exclude some data that I believe should have been included. The ones that do not give details seem to give EV's less credit than makes sense. There are some that show that EV's are worse with specific pollution like NO2, Well-to-Pump (WTP) because of coal fired plants, but they don't seem to reflect BEVs are most commonly charged at night (which means the energy as lower pollution due to several factors). Here is a nice critique of the Argonne Wells-to-Wheels (WTW) study, https://sites.google.com/site/nwpri...eenhouse-gas-emissions-from-electric-vehicles showing that actual driving data differs from Argonne's estimated driving efficiency yielding very different conclusions.

Without such details I am inclined to agree with charlie1300 since authors tend to favor data to get the result they want. As he says, it defies common sense that a BEV doesn't pollute less WTW:

- Well to pump: (pump being the EVSE) BEV's should win b/c the source fuel is going a shorter distance before it is converted into gasoline/electricity and refining is less efficient than conversion of coal/gas/water/uranium to electricity. There is transmission loss, but that's still got to be less than trucking it from the refinery to the gas station. Sure coal fired plants are nasty, but they are getting better and are quickly being replaced by cleaner NG.
- Pump to tank: ICE wins b/c of inverter loss ~15% vs the tiny amount electricity to pump gas
- Tank to Wheels: EV's win big time.

I agree that trying to find a common standard between studies of how for back to go is nigh unto impossible. I will say that the most common number I've seen for energy used in refining gas/diesel is that it adds about 15% to the fuel's CO2 (directly from the engine's combustion). Wiki has the following to say re grid losses:

"Transmission and distribution losses in the USA were estimated at 6.6% in 1997[10] and 6.5% in 2007." http://en.wikipedia.org/wiki/Electric_power_transmission#Losses" onclick="window.open(this.href);return false;

I thought it was more like 4%, but that may have been referring to a subset of total losses. BTW, one book I have, "How to Live a Low-Carbon Lifestyle" by Chris Goodall, indicates that walking instead of driving for short trips (up to 2 miles) can use about the same energy if not more than driving, because of the intensive energy use in western industrial food practice. He calculates the energy needed for a glass of milk to supply the calories to walk various distances, and says that it takes on average 9 calories of energy to produce 1 calorie of food.

I'll continue to walk for those trips, because being in better shape and staying out of the hospital is likely to save far more CO2 down the road, and it definitely provides me with a higher quality of life.