The Study I've Been Waiting For: UCS on EV Costs, Emissions

[Alric]

Something else missing from the article is that even on "dirty areas" you can offset your emissions by purchasing renewable energy. Once I thought this was mainly symbolic but, at least in my area, the power company buys energy from actual wind, solar and (regrettably) natural gas sources. In my area the renewable offset is 66% wind, 30% gas and the rest solar.

I offset 100% of the energy use of my home this way.

 

[Stoaty]

In my area the renewable offset is 66% wind, 30% gas and the rest solar.

Do you mean an offset, or that you are purchasing renewable energy? At Los Angeles DWP you can sign up for Green Energy. Costs 3 cents per kWh more. Supposedly they are contracting for that amount of renewable energy for you, in addition to renewable energy required to meet state renewable portfolio standards (so there is no double counting).

 

[mywaracfirfoyff]

Nearly half (45 percent) of Americans live in BEST regions—where an EV has lower
global warming emissions than a 50 mpg gasoline-powered vehicle, topping even the
best gasoline hybrids on the market. Charging an EV in the cleanest electricity regions,
which include California, New York (excluding Long Island), the Pacific Northwest, and
parts of Alaska, yields global warming emissions equivalent to a gasoline-powered vehicle
achieving over 70 mpg.

All that, even though they don't include upstream emissions from the production of diesel or gasoline.
(Which seem to be pretty huge)

Thanks!

 

[mywaracfirfoyff]

Nearly half (45 percent) of Americans live in BEST regions—where an EV has lower
global warming emissions than a 50 mpg gasoline-powered vehicle, topping even the
best gasoline hybrids on the market. Charging an EV in the cleanest electricity regions,
which include California, New York (excluding Long Island), the Pacific Northwest, and
parts of Alaska, yields global warming emissions equivalent to a gasoline-powered vehicle
achieving over 70 mpg.

All that, even though they don't include upstream emissions from the production of diesel or gasoline.
(Which seem to be pretty huge)

Thanks!

Looks like I spoke too soon.
They indicate that they did use well to wheels emissions for both gasoline powered vehicles and EVs.

I could not find numbers they used for upstream emissions for gasoline. I'd be interested to see what they came up with (and how).

Thanks!

An Apples-to-Apples Comparison of EV and Gasoline Vehicle Global
Warming Emissions
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.

 

[GotMyleaf]

The report states that well-to-wheels was used but the numbers don't add-up to me. Oil refineries use so much electricity that the largest ones have their own on-site power plants. That fact alone tells me that there is no serious comparison being done.

With the amount of electricity (6-7kw) used to produce a gallon a gasoline alone, a comparison could be done and an EV would be more efficient.

I think that this study is another load of crap.

 

[Pipcecil]

I wonder if gasoline engines should have a weighted value. Emissions, even GHG, are more subject and reactive when they are combined and concentrated (causing health problems and/or climate problems) versus having the freedom to disperse. Preventing and reducing emissions in a non-attainment area (big cities like Dallas, Houston, New York, Chicago, etc.) and moving those emissions to a power plant in the middle of no where that can handle the addition emission capacity into the environment (i.e the ecosystem being able to asorb the CO2 and O3) is still a benefit and shouldn't be discounted. How much help is this, if any I don't know (I only get to dabble in air quality), but there is a benefit to this.

 

[lpickup]

Let me first say that I'm not trying to troll here and I'm definitely on the side of thinking that refineries are horribly inefficient and electric is THE WAY to go.

BUT, I feel I need to correct this statement as it is oft-repeated by the EV community, and I think we have a strong enough argument without relying on this statement as it is written and similar exaggerations. I think we need to take the high road and here and present factual arguments, unlike the naysayer crowd that frequently uses made up stats to make their point.

So anyway, I have to take objection to this statement:

With the amount of electricity (6-7kw) used to produce a gallon a gasoline alone, a comparison could be done and an EV would be more efficient.

They use that much POWER, but not necessarily that much electricity. They actually buy very little electricity from the grid, and this is actually fairly well documented. Most of the POWER comes from waste heat as a result of the refining process itself. Basically the way this shows up in the math is that they put X worth of energy (in terms of raw materials and external power sources) into the refinery and get Y out. If you calculate the amount of energy in the "lost" raw materials with the amount of external power used, that's how you arrive at that 6-7kWh number.

I still think it's a valid point that refineries are inefficient beasts. And a well to wheels analysis needs to take that into account (and while I haven't seen the actual data from this report, they do say it was taken into account). Plus I think this report was looking at it from an emissions standpoint, not an energy efficiency standpoint. So it doesn't mean the report is a bunch of crap. It just means that there are other reasons in additions to what they reported on to consider EVs.

 

[mywaracfirfoyff]

So anyway, I have to take objection to this statement:

With the amount of electricity (6-7kw) used to produce a gallon a gasoline alone, a comparison could be done and an EV would be more efficient.

They use that much POWER, but not necessarily that much electricity. They actually buy very little electricity from the grid, and this is actually fairly well documented.

From http://205.254.135.7/emeu/mecs/iab98/petroleum/energy_use.html" onclick="window.open(this.href);return false;

Petroleum refining is the most energy-intensive manufacturing industry in the United States and accounts for about 7.5% of total U.S. energy consumption.
...
Energy Consumption by Fuel
Refinery gas, natural gas, and petroleum coke account for the largest shares of energy use
...
Onsite Generation
The petroleum industry produces about 32% of electricity onsite

I'm not sure if this supports your statement or not, but here it is.

Most of the POWER comes from waste heat as a result of the refining process itself. Basically the way this shows up in the math is that they put X worth of energy (in terms of raw materials and external power sources) into the refinery and get Y out. If you calculate the amount of energy in the "lost" raw materials with the amount of external power used, that's how you arrive at that 6-7kWh number.

I think the real question here is, could this be directly comparable?

If the plant was not refining gasoline, but instead generating electricity, how much energy would you get out? Would you be better off that way instead of burning the gas in tiny ICEs?

Or perhaps, if instead of generating electricity by burning the heaver and lighter parts of the stack, they used energy from the grid, would their emissions improve?

Thanks!

 

[mywaracfirfoyff]

The report states that well-to-wheels was used but the numbers don't add-up to me. Oil refineries use so much electricity that the largest ones have their own on-site power plants. That fact alone tells me that there is no serious comparison being done.

I do wish they would have sourced their numbers on the refinery side. The numbers on the electrical generation side are already fairly well understood. Perhaps this is why they were able to source them so well, and had to be vague on the refining side.

I suspect that the petroleum industry PR types knows that these numbers make them look bad, and as such they will try and keep them under wraps.

Thanks!

 

[lpickup]

I think the real question here is, could this be directly comparable?

If the plant was not refining gasoline, but instead generating electricity, how much energy would you get out? Would you be better off that way instead of burning the gas in tiny ICEs?

Or perhaps, if instead of generating electricity by burning the heaver and lighter parts of the stack, they used energy from the grid, would their emissions improve?

Thanks!

I don't think it is directly comparable. That's why I approach it from the efficiency standpoint. One of the problems you run into is you can't just assume they are not producing gasoline but rather producing just electricity. I don't think it works that way. In a sense, the power is a byproduct of the refining process so you have to be refining to get it anyway. And looking at it the other way, you have to burn the raw fuel anyway, so you may as well use it to power your process.

Having said that, I think it is fair to make the argument that the refining process uses the EQUIVALENT of 6-7kWh of power to produce a gallon of gas. I have no qualms at all about saying that if you didn't refine that gallon of gas because my vehicle doesn't need it to travel 25 miles, but just the energy you save in not refining it is enough to power my LEAF for that same 25 miles.

In fact though, not refining that gallon of gas essentially buys you the equivalent of about 1.2 gallons of gas saved.

Of course the naysayers will continue to say that we benefit from all the other byproducts of petroleum refining so we have to refine gas just to get those. Yeah, that's what we need, another bazillion plastic grocery bags winding up in the Pacific Ocean.

 

[lpickup]

I suspect that the petroleum industry PR types knows that these numbers make them look bad, and as such they will try and keep them under wraps.

That's exactly why we'll never see the real numbers. I'm sure they are closely guarded.

This is probably the best data you're going to get: Updated Estimation of Energy Efficiencies of U.S. Petroleum Refineries

 

[Alric]

In my area the renewable offset is 66% wind, 30% gas and the rest solar.

Do you mean an offset, or that you are purchasing renewable energy? At Los Angeles DWP you can sign up for Green Energy. Costs 3 cents per kWh more. Supposedly they are contracting for that amount of renewable energy for you, in addition to renewable energy required to meet state renewable portfolio standards (so there is no double counting).

It seems it is actual purchase of renewables. Sadly it includes natural gas. This is the mix they claim:

http://db.tt/4CrA7sFW" onclick="window.open(this.href);return false;

 

[lpickup]

It seems it is actual purchase of renewables. Sadly it includes natural gas.

Well, biogas does not equal natural gas. However, you are correct to be a bit disappointed. There are studies that show biomass does do more harm than good when it comes to emissions, and biomass does use land area that might otherwise be used for food (or not--I guess it depends on the area you're talking about). But strictly speaking it is mostly renewable.

 

[Alric]

It seems it is actual purchase of renewables. Sadly it includes natural gas.

Well, biogas does not equal natural gas. However, you are correct to be a bit disappointed. There are studies that show biomass does do more harm than good when it comes to emissions, and biomass does use land area that might otherwise be used for food (or not--I guess it depends on the area you're talking about). But strictly speaking it is mostly renewable.

You know what? I read that as "natural gas" but in terms of emissions they are prob about the same. I'll take the 66% wind though. This combo is definitively much better than coal.

 

[lpickup]

You know what? I read that as "natural gas" but in terms of emissions they are prob about the same. I'll take the 66% wind though! This combo is definitively much better than coal!

It depends on what the source material for the "biogas" is. If it's animal waste or dead plant material, then that's fine. But if it's live plant material that they are harvesting to burn (usually this is in the form of trees) then the argument goes that the tree could've still absorbed additional CO2 if it wasn't killed.

However, I think usually when trees are harvested and converted to biomass, they are already being harvested for another purpose (i.e. lumber, paper) and they just take the less useful parts (twigs, leaves, small branches) and use those parts that would otherwise be wasted into biomass.

 

[Alric]

I looked into "biogas" and found this page from my provider

http://www.wppienergy.org/rep" onclick="window.open(this.href);return false;

Interestingly it says:

Biogas. Landfill gas is converted into electricity, significantly reducing methane (a greenhouse gas) and lessening air pollution.

And the wikipedia entry: http://en.wikipedia.org/wiki/Biogas" onclick="window.open(this.href);return false;

So I would think it is comparable to natural gas but much better than the alternative methane and NO2 production.

 

[DaveEV]

So I would think it is comparable to natural gas but much better than the alternative methane and NO2 production.

The alternative is typically burning it off with a flare converting the methane to CO2.

Capturing it, cleaning it up and mixing it with the natural gas supply is a popular thing to do to get some work out of it while burning it.

Here's a great example of one such setup locally: UCSD Installing 2.8 Megawatt Fuel Cell to Anchor Energy Innovation Park - January 3, 2011

 

[GotMyleaf]

I get frustrated with these studies because, after driving an EV daily, it's easy to see the cost, time and energy assocoated with ICE's. They are numerous.

I did a little research on the top-ten U.S. refineries (by production) and found that many of them have their own power plant on-site and that most of them ise natural gas.

Any process that uses so much electrical power that it makes sense to build a dedicated power plant is a clue as to how much power is required. Based on that evidence alone, I think that it is safe to say that the electrical used in the refining process should be added into the total emissions of a gallon of gas.

Ignoring such a huge factor invalidates any emissions calculation.