Fresh And Easy scores a near miss...

[EvansvilleLeaf]

No it makes a very big difference. The last two zipcodes I have had were at 72.9% coal and 23.1% coal (latter vast majority hydro, which is 24 hr constant source). Cars charging on either grid would have very different emissions source to wheels.

The curious can find theirs here:

http://www.epa.gov/cleanenergy/energy-and-you/how-clean.html" onclick="window.open(this.href);return false;

Coal average is just under 49% btw.

Core Leaf markets in the Bay Area and LA are only 7.6% coal.

 

[Ingineer]

Coal is coal, no matter where you are. I specifically referenced the CO2 for coal. Since most EV charging is expected to be done at night, and since most night time additional load in the US will come from coal, the generalization does indeed apply to a large portion of the US.

Also, most petroleum refineries also operate at night to take advantage of cheap electricity, the same you speak of! Add the flare and methane gas CO2 on top the 10kWh Coal CO2, and top it off with the CO2 out the tailpipe and you are choking on it!

Whereas I can drive my Leaf over 40 miles on just that coal CO2, no need for the flare/methane or the tailpipe CO2!

Then there's the fact that I live in California, where our primary source is Natural Gas rather than coal. But even if I personally don't have solar, California still leads the Nation in electricity generation from nonhydroelectric renewable energy sources, including geothermal power, wind power, fuel wood, landfill gas, and solar power. California is also a leading generator of hydroelectric power.

These facts can be found on these web sites:
The US Energy Information Administration (EIA)
The US Department of Energy (DOE)

-Phil

 

[JRP3]

You are missing the point and clouding the issue by talking about your personal circumstances, it's irrelevant to the discussion.
Additionally, the percentage of coal use for the grid skyrockets at night, when most EV's will be charging.

 

[Ingineer]

Your numbers are way off. First of all much of the electricity used for refining is produced on site in co-generation plants, which also supply power to the grid. Second, if you use the purchased electricity figures compared to the gallons produced it's less than 1kwh per gallon. The DOE puts gasoline production efficiency at better than 80% for the full cycle, which works out to less than 6kwh of energy per gallon, but that energy is not necessarily electricity. Refining takes heat, which is directly fueled from petroleum products, including NG. Well to wheels a Prius has a slightly smaller CO2 footprint than a coal powered LEAF.

Way off? I don't think so. You aren't even taking in to account the distribution phases, only refinement. Show me the figures, because what I have seen doesn't even come close to what you are asserting. Distribution of petroleum is a huge energy cost, from drilling, pumping, pipeline operations (they have to heat and pressurize to 600psi!), oil tanker, terminals, local tanker trucks, gas station pumping, etc. I have never seen a TRUE well to wheels study done, because our petroleum has to many divergent sources and is constantly changing, so I know you can't produce any hard figures.

If you take JUST the known quantities, such as just the 4' diameter Alyeska pipline I mentioned before, which contains 380 million gallons of oil, it's 10 pumping stations at 600psi and 145 degrees, only one of which used 87.3 million kWh of grid electricity in 2008, along with 10.4 million gallons of Diesel, and 4.8 million MCF of Natural Gas. Then once the pipeline ends, you must pump the crude into tankers, like the Exxon Valdez, and power them on heavy bunker oil to terminals at the refineries. And this is just the little trickle of oil we get from Alaska!

-Phil

 

[thankyouOB]

You are missing the point and clouding the issue by talking about your personal circumstances, it's irrelevant to the discussion.
Additionally, the percentage of coal use for the grid skyrockets at night, when most EV's will be charging.

you keep repeating yourself no matter what sources or information others provide.
i dont think that works as a persuasive argument or factual analysis.

 

[Ingineer]

I'm sure we could go toe-to-toe all day like this, and I'm not going to, because it's silly.

The fact remains, no matter how you slice it, both coal and petroleum are non-renewable sources, and so ultimately be replaced. Since you cannot replace the gasoline with any equivalent renewable but you CAN right now, replace an EV's energy source with 100% renewables, there simply is no argument you can make.

Also, we need the petroleum for so much more than just transportation so people can drive their SUV's around; we need plastics, fertilizers, pharmaceuticals, etc. I'm not proposing we stop using it, but we should conserve it for the things that matter. If we can switch OTR trucking to electrified rail, and personal transportation to a mix of technologies, the bulk of which is sourced from renewables, then we have a future. Otherwise we don't have much longer.

Stick that in your SUV and smoke it! =)

-Phil

 

[MrFish]

You are missing the point and clouding the issue by talking about your personal circumstances, it's irrelevant to the discussion.
Additionally, the percentage of coal use for the grid skyrockets at night, when most EV's will be charging.

I don't have a dog in this fight, surly don't want to speak for others but I have a problem with misleading statements that are being used to diminish the positive impact of the EV.

There is no such thing as "the grid" in the United States rather we have a complex and loosely connected network of power generating plants and power transmission systems so the energy generation matrix on one network is completely different from another. That means it is inaccurate to state that coal usage increases at night for the "grid". The percentage electricity production by coal may increase on a particular network however is may remain unchanged or decrease on another. The second misquoted inference is since the percentage of coal produced electricity increases at night, that must equate to an increase on coal usage and therefore increased CO2 production to meet the EV charging load. In fact, Gas and coal fired power plants take several days to start up and there after must run at a constant level. At night when electricity usage decreases these plants can not be "turned down" and they consume a constant amount of energy regardless of the load being placed on them, so power system managers turn to other generating sources like hydroelectric to decrease production since they can be rapidly turned on and off thus explaining the varying percentages of coal production. In fact coal plants produce a fairly constant level of CO2/CO pollutants even at night when there is an excess of production capacity. The charging of EV's at night actually increases a coal plants efficiency and decreases the CO2 production/KW.

Sorry for ranting.

 

[JRP3]

I'm sorry but that is not at all an accurate assessment of how the grid operates. Coal plants do indeed ramp down at night, and NG plants are called Peaker plants and can ramp up and down rapidly.

 

[JRP3]

I think many of you may be misinterpreting my viewpoint. You won't find a stronger EV advocate on the planet than myself. As such I find myself in similar arguments all the time, and because of those arguments I learn quite a lot. Not so long ago I argued the same points many of you are making but was provided with credible data to realize that nighttime EV charging will be largely from coal, and that vehicles charged in such a manner will have slightly higher emissions than a Prius. Part of a long but informative discussion with Glenn Doty of WindFuels can be found here: http://seekingalpha.com/article/308...exide-technologies-the-sequel#comment-2047808
His posting on NG charging is here: http://seekingalpha.com/article/312...ce-step-the-electric-crawfish#comment-2135516
His description of night time grid profile is here: http://seekingalpha.com/article/312...ce-step-the-electric-crawfish#comment-2187316
It's worth wading through to read all of his comments. I don't agree with all of his conclusions of course but his grid numbers are hard to argue with. I have not found good sources to contradict his numbers regarding night time generating profiles.

 

[Ingineer]

I'm sorry but that is not at all an accurate assessment of how the grid operates. Coal plants do indeed ramp down at night, and NG plants are called Peaker plants and can ramp up and down rapidly.

Wow, this shows how little you know. Coal plants definitely do not "ramp" well, they are used as base load sources. In order to run efficiently, and meet the current emissions profile restrictions in the US, coal plants must be run at a very narrow band. Natural gas is indeed often the fuel of choice for peaker plants, but not all NG plants are capable of peaking, and not all peaker plants use NG. Many use oil.

One of the beauties of many renewable sources, is that their output can be easily adjusted, so they are often used perform the peaking function. Hydroelectric being most common.

I suggest you take your BS elsewhere, as this forum is not likely to buy into it. We know the truth here!

-Phil

 

[Ingineer]

Keep in mind, if we had a lot more EV's on the grid, especially with smartgrid and/or V2G technology, it would have a stabilizing effect, and less if not all peaking plants would be needed which are usually dirty and inefficient.

So if in the future we achieve a high grid stability factor using EV's and V2G, the efficiency and therefore emissions will improve greatly.

Right now one EV in a coal-derived area might add slightly to the CO2 footprint, but definitely not more than a Prius. In the future this impact will definitely lessen, and the Prius will be much more dirty in comparison.

The neat thing about electricity, is while it doesn't store well (yet), it's very fungible and we already have the infrastructure in place. We can take advantage of this to phase in renewables as we see fit, without any huge changes or impossible infrastructure changes.

-Phil

 

[JRP3]

This is beyond amusing that I'm being painted as some uniformed anti EV troll. :mrgreen:
Hydroelectric is usually considered baseload, as is nuclear. Coal is baseload but it can and does ramp up and down, coal plants do not usually go full steam all night long. Just think of all the states that are almost 100% coal powered, what happens to all their excess power at night if they can't lower the output?

 

[JRP3]

Keep in mind, if we had a lot more EV's on the grid, especially with smartgrid and/or V2G technology, it would have a stabilizing effect, and less if not all peaking plants would be needed which are usually dirty and inefficient.

So if in the future we achieve a high grid stability factor using EV's and V2G, the efficiency and therefore emissions will improve greatly.

Of course, and completely irrelevant to the argument we are having.

Right now one EV in a coal-derived area might add slightly to the CO2 footprint, but definitely not more than a Prius. In the future this impact will definitely lessen, and the Prius will be much more dirty in comparison.

This is the argument we are having, and the numbers I've seen suggest otherwise. If you have CO2 per mile numbers for a LEAF charged from coal showing better CO2 per mile than a Prius please show them.

The neat thing about electricity, is while it doesn't store well (yet), it's very fungible and we already have the infrastructure in place. We can take advantage of this to phase in renewables as we see fit, without any huge changes or impossible infrastructure changes.

Agree, of course, but still off topic. I am making a very specific point about coal charged EV's vs HEV's, even more specifically a coal charged LEAF vs a Prius. Any other points are rather off topic.

 

[Ingineer]

This is beyond amusing that I'm being painted as some uniformed anti EV troll. :mrgreen:
Hydroelectric is usually considered baseload, as is nuclear. Coal is baseload but it can and does ramp up and down, coal plants do not usually go full steam all night long. Just think of all the states that are almost 100% coal powered, what happens to all their excess power at night if they can't lower the output?

You may not be directly anti-EV, but you are spewing wildly inaccurate information, which many other people love to use as arguments against EV's.

Hydroelectric can be scaled down instantly, as easy as closing a valve. Mind you, it's a big valve!

Coal does not scale or vary, especially not in modern cleaner plants which must run in tight bands to stay clean.

Even nuclear plants slide better than coal, I don't know where you are getting that from!

As you yourself pointed out, states are not isolated! Our "grid" allows interconnection so that power can be bought and sold as needed for efficiency, capacity, and redundancy. There are no 100% coal derived states. Check the REAL STATS on the DOE web site I linked. They may indeed have significant baseload derived from coal, but they run peaker plants on other sources, or buy power from other grid partners that can easily have variable demand, such as hydro. They might also buy extra power during the day, and sell some of their excess coal baseload at night. They definitely don't use coal for variable demand!

-Phil

 

[JRP3]

Yes hydroelectric can be used as a peaker plant as well as baseload but it's mostly used as baseload because it's the cheapest electricity available and as such is run near full capacity. It makes no sense to curtail hydro and use some other more expensive source.

 

[Ingineer]

You may be choosing to only argue some narrow point, but I am not! Your "very specific argument" is nonsensical, because you are not looking at the full picture. It's most definitely relevant to consider the future, not doing so is what got us into this mess in the first place! If you refuse to consider the long-term effects, then it just further demonstrates your narrow-mindedness and reinforces why people thinking like you are such an obstacle to fixing all this.

Many people here that own Leafs also have PV installed on their homes. That is doable NOW, and means you can avoid this "narrow (minded) argument" you are making entirely. Either they directly charge from solar during the day, or they sell power during peak times to the grid and charge at off-peak using the grid. The latter actually improving the situation even more so than directly charging from the sun.

I can easily demonstrate that a grid connected EV charging AT ANY TIME in any state in the US is cleaner and more efficient than using a Prius sourced by gasoline. If you simply took out the subsidies our government places into petroleum, the economics alone would make it almost impossible to consider NOT driving an EV!

I couldn't give you accurate figures for well to wheel without knowing exactly which well and which path that gallon of gas took to reach your tank, and the true cost of all the subsidies, such as the energy our military is consuming to ensure that supply. But I can do a best-case estimate, and that easily puts it over 10kWh per gallon, as I originally stated.

If you can prove otherwise, show me the numbers or quit typing nonsense.

Enough time wasted here, I'm off to something more constructive for the future of our planet.

-Phil

Of course, and completely irrelevant to the argument we are having.

This is the argument we are having, and the numbers I've seen suggest otherwise. If you have CO2 per mile numbers for a LEAF charged from coal showing better CO2 per mile than a Prius please show them.

Agree, of course, but still off topic. I am making a very specific point about coal charged EV's vs HEV's, even more specifically a coal charged LEAF vs a Prius. Any other points are rather off topic.

 

[JRP3]

Here is a link to a 24 hour generating profile, notice the drop in coal output that would be ramped up with additional loads from night time EV charging, page 5 of the PDF:
http://iopscience.iop.org/1748-9326/4/1/014002/pdf/erl9_1_014002.pdf
Also notice that nuclear and hydro are considered baseload.

 

[Ingineer]

Wow, what a true narrow-minded person you are, even that study you quoted from, which you clearly didn't even fully read, states this right in the beginning:

The work presented here considers the impact of transferring emissions in one sector (on-road vehicles) to emissions in another sector (EGUs). Bradley [11] evaluated the effects of switching emissions between sectors and found that switching from conventional vehicles to PHEVs charged using coal-fired electricity would lead to emission reductions of NOx, VOC, CO and CO2 . As described later in this paper, this work confirms those findings but then examines the air quality impacts (i.e.: ton ozone formation) of shifting the emissions in time and location.

FYI: EGU is an acronym of Electricity Generating Units, or Power stations.

Then they affirm the previous data and make this conclusion:

4. Conclusions:
Air quality modeling of the four state classic PJM area show that substitution of PHEVs for just 20% of the mobile vehicle fleet VMT would reduce ozone by up to 8 ppb in the most densely populated areas in the PJM. The benefits would increase if cleaner sources are used to charge the PHEVs or if, subject to the availability of additional excess generation, PHEVs are substituted for a larger percentage of the mobile fleet."

Also, This study was on PHEV's, not EV's, which have higher efficiencies, and zero emissions output themselves.

By the way, on page 5 they never show that coal plants are scaled, they just show the total outputs from each type. This likely means the coal operators sold their excess capacity to another operator on the grid.

The study is actually very interesting and notes many other Pro-EV facts:

A study by the Pacific Northwest National Laboratory (PNNL) found that the existing electrical infrastructure and capacity could support a switch to PHEV by 84% of US cars, pickup trucks and sports utility vehicles assuming nighttime charging.

Another study, conducted for California, concluded that existing capacity has the capability of supporting PHEV nighttime charging.

Now please go away. I suggest you actually READ once in a while, especially from sources you quote from!

-Phil

Here is a link to a 24 hour generating profile, notice the drop in coal output that would be ramped up with additional loads from night time EV charging, page 5 of the PDF:
http://iopscience.iop.org/1748-9326/4/1/014002/pdf/erl9_1_014002.pdf
Also notice that nuclear and hydro are considered baseload.

 

[Ingineer]

One last thing, sorry Tom for hijacking your thread. I'd like to ask that a moderator split the latter part of this thread out into a new one with an appropriate title, such as "EVs have more emissions?".

-Phil

 

[DaveEV]

Also, most petroleum refineries also operate at night to take advantage of cheap electricity, the same you speak of! Add the flare and methane gas CO2 on top the 10kWh Coal CO2, and top it off with the CO2 out the tailpipe and you are choking on it!

fueleconomy.gov includes upstream emissions in their CO2 emissions (data from GREET) where one can see that upstream gasoline CO2 emissions are about 25% the tailpipe emissions.

So a 50 mpg 2012 Prius has about 178 g/mi tailpipe emissions and 44 g/mi upstream emissions - a total of 222 g/mi.

Coal power is around 900 g/kWh, natural gas is around 450 g/kWh (full lifecycle). Plug in your EV's efficiency data and it's easy to see looking at back-of-the-envelope calculations that if you get a lot of your electricity from coal, it's can be a little bit worse than a Prius in terms of CO2 emissions - and again - that includes upstream emissions.

And as JRP3 states - yes, coal plants can definitely be ramped. Yes, they don't like to be ramped and emissions of any power plant tend to be lower when ramped quickly up/down, though the newest combined cycle gas plants from GE/Siemens are much better in this regard.

"Baseload" is really a misnomer - in real life the cheapest power plants to run, tend to get run the most and ends up being "baseload". So this means Nuclear and renewables since there is basically no fuel cost. They will always be able to underbid the fossil fuel plants. Coal is next (coal is cheap) and then natural gas. In the last couple years with low, low gas prices gas has been taking away market share from coal. Natural gas turbine plants tend to be used as "peaker" plants to account for varying load since they're the cleanest and easiest to quickly ramp up/down.

JRP3 has taken a bit of bashing here unfairly as his numbers are in the right ballpark overall. He deserves an apology.

--

Back on topic - "Green Parking" spots are a gimmick. I'd rather see the effort put into other "green" initiatives.