Prius v (in 10 weeks) Outsells Chevy Volt for 2011

The PEF was an adjustment for CAFE standards which are not directly about the best way to measure energy useage,, they are a mixed estimation incentive. In defining that they examine, (in the 90's) the U.S. average fossil-fuel electricity generation efficiency, and just used that. In their justificaiton published in the Federal register
Federal Register, Volume 65 Issue 113 (Monday, June 12, 2000)
They even admit

Therefore, DOE has continued to use the value of Eg =
0.328 in light of: (1) the commentors' clear desire to place a higher
priority on timely publication of a final rule, than on performing
additional technical analyses; and (2) since the fossil generation
component will dominate the marginal electrical generation efficiency
for many years.
​

They decided not to go back and address the issues of renwables, and just move forward with "fossil fuels" dominated number and ignore things like cost of distribution for gas even though they include the distribution cost for electricity.

Realistically, since the EV side was already getting a bonus bump (the full formula divides by .15 as a "fuel content factor"), it was not a killer issue and people let it pass. If pushed to change the .328 they would likely have just adjusted the .15 to keep the ratio the same.. (since is seems there was a political agenda driving things). But they did not want to adjust the .15 because it was tied to prior rules.


So the PFF needs to be used as a whole formula, not just cherry picking the numbers you like out of context.

Note the PFF data was from the 1990's. The grid has gotten much cleaner since then. Consider the following chart from EIA showing how much renewable and nuclear has added.



Renewable energy is more difficult to include as some people think "efficiency" measures efficiency against what we could get (e.g. a current wind generator only extracts x% of the wind energy.. ), others, including me, focus on fuel used.


Note even there its based on what was generated, not what could have been used. It has been reported the 2010 the US idled 25TeraWatts of Wind energy, because it easier to idle wind at night compared to other generators. That biases the answers in terms of fossil fuel, but also means the incremental power needs of EVs at night could be almost all satisfied by renewables. 25TW is about 700 Million gallons of gas equivalent, that the country just threw away never to see again. I think that number is high, but even if only half it was included in the renewable side and coal use reduced the efficiency would be even higher. But since its not generated (just idled) its not in the EIA data.. and some people actually use that to argue wind is less efficient because it "wasted" that energy. (There is a lot of polotics around energy because of the money involved.)

For info on the curtailed wind energy see
25 TWh of Wind Power Idled in 2010 in US – Grid Storage Needed | CleanTechnica


Combing back to your question on how to compute it, for how I believe you can compute it more accurately including renewable energy,
See my post
http://priuschat.com/forums/prius-h...46-mpg-hwy-under-19-000-a-25.html#post1452680

 

We use MPG/MPGe because they are measure of efficiency on a standardized test. I agree its a weak test, but its still the best test we have.

What data do you suggest? There is no standardized reporting of Prius gas usage, just self-reported data, which is generally subject to the self-reporting bias.. those taking that much effort tend to be more efficient. Voltstats.net is more automated but stil subject to a self-selection bias. But even with the that bias data, its 4-6% below EPA.

I don't really want to argue about the rest of their products. I'm not a GM fan, just a Volt and EV supporter. But its ironic to talk about cherry picking then to cherry pick your examples. Toyota's top selling car is the Camry with combined 26 and Corolla with 29.

 

Even if Volt sales "flounder" at the recent sales pace of 10,000-20,000 a year it will be selling at about the same pace as almost every hybrid model other than the Prius. Although that would be lower than the sales targets announced by GM I wouldn't consider that to be a failure. Realistically, it is scary new technology, politically controversial, and more expensive than average and that generally means lower sales at least for the first several years.

I hadn't noticed how low the sales numbers are for non-Prius hybrids until very recently. Here are the cumulative sales lists for 2011 and 2010:
December 2011 Dashboard: Sales Still Climbing | Hybrid Cars
December 2010 Dashboard: Year End Tally | Hybrid Cars

 

I have been actively following gm-volt.com since 2007 and have read most of what was posted there during the last several years including the comments on the front page articles while Lyle Dennis was still writing them.

I am also one of the earliest Prius owners in the U.S., having ordered my 2001 and 2004 cars at the earliest opportunity and having received each of them about a week after john1701a picked up his (according to his web log). I still own them although other family members often drive them now. They are awesome cars. I think I would have been sensitive to Prius bashing.

Our perceptions differ. I don't recall much Prius bashing there other than the usual generalized xenophobia. What I recall was enthusiasm for the Volt concept and lots of discussion and speculation about Volt features or related technology like Lithium batteries.

I recall John posting there many times over the years. I think I recall you posting there as well for awhile although I don't see any results from googling and don't see you there as a current forum member (were your comments purged?).

I think the common perception there was that you and John were "smug" Prius fanbois who were trolling there by trashing GM and the Volt as a way of defending the Prius (although it didn't really need much defending).

I hope I'm not viewed as a troll over here. I find the discussion here a bit more lively than gm-volt. I've been posting here recently because I've sometimes noticed a lack of information about the Volt. I'm also interested in sharing and learning information related to the PiP (which looks likely to be a great car for many drivers) and other plugin hybrids.

 

GALLONS and KWH per distance. There's nothing complicated about that. The measure of MPG tells almost nothing about actual efficiency.

Listed were the 2 next most efficient choices available, nothing picked. Remember, the point is to replace the current top-sellers.

Who said failure? There are lots of vehicles that only sell at niche quantities. In fact, that can be a category of praise. The question is, how will Volt break out beyond that level to become mainstream?
.

 

Another bias in the voltstats.net mpg data is that most of the cars in their database joined after November 9 so their overall average mpg is being lowered by a disproportionate amount of their data being logged under cold Winter temperatures.

Also, the cars which are driven almost entirely on battery power may end up reporting CS mode mpg which is dominated by the Volt occasionally starting the engine in CD mode at ambient temperatures under 26F to assist with cabin heating. Even though little gasoline will be used by these cars, they may report unusually low mpg numbers that are not characteristic of actual gasoline consumption while driving under CS mode.

 

Sadly, if you support a competitor's vehicle, you automatically get put into that trolling category. Guilty until proven innocent is really a pain to overcome. It can be done, of course. But try correcting misinformation along the way, you're doomed. And those in favor of Volt dropped so much bait, it was impossible to resist.

I was hosed right from the start anyway, questioning how such a system could deliver 50 MPG after depletion with a 40-mile range all for under $30,000. It didn't make any sense, especially having already studied all the hybrid designs so extensively.

No matter what you said, it was spun to sound like you were defending Prius. Then when I asked about the effects of winter, it really hit the fan. They believed there was simply no way the cold would drop efficiency that much... yet, that's exactly what happened.

Efficiency competition should be traditional vehicles. But with such a high base price on Volt, it's easy to see promotion of Prius PHV as negative for Volt.

So, what should we do now?
.

 

MPG and GPM are just transforms (inverse) except when G=0.
MPGe to kWh/mile (for just EV mode) just multiply by 34.2.
Neither of this is a change in data, just in the representational basis.

The different basis does not allow one say anything more about efficiency. Its the same data in different forms.

The point of MPG and MPGe was to put them on a common basis to allow easier comparisons, especially when considering blended operation. When blending energy sources, the blending percentages matter a lot.

 

Compare Side-by-Side

Shows combined 36 kWhr / 100 miles for 2011 Volt in EV and 190 g/mi CO2 in this area.

for comparo, 34 kWh/100 mi for Leaf and 120 g/mi in 94587 area code.

Did someone mention there's no kWh/mi rating for Volt?

Obviously what many are ticked about is Volt's appetite for premium gas and emissions when the party is over ... and the price .. and me for not being able to sit in the back of one (worse than backseat of my Accord Coupe)

 

It would be good to see some of this type of discussion over on gm-volt.com People there need to know the facts just as much and be able to defend their position.


I've no power at either place so cannot magically solve any problem. I'm sure there are some here that consider me a pain. (I hope I'm not views as a troll as I don't post things to get a response-- i respond to post which then starts a discussion. )

What should "we" do now.. If you've been banned at gm-volt write to a moderator and ask to be allowed back. or tell me who banned you and I'll PM them to allow you back in. (I've been banned from sites and let back in . If your IP is banned, you might try this nice open-source thing called TOR.. it protects your privacy in very nice ways, including your IP address.


Also if you want to avoid being banned, its better to respond to posts rather than start provocative threads with grand claims. I try not to post on priuschat (or mynissianleaf or ecomodler or other car sites) about the volt unless its in response to other posts.. I'm not here to push an agenda as much as to keep the facts straight and engage in intellectual discussions. And when I see errors in fact at gm-volt.com I'm quick to point them out there too.

There are various prius threads at gm-volt try posting some stuff under
Electric Car Competitors
if its presented as a discussion, and not just a put trollish down, I'll staunchly defend your right to present, even if I disagree with your statements.


If you talk about efficiencies of Prius PHV and make meaningful comparisons I'll be discussing it with you and defending your right to discussion. If you show up and say the volt is a failure I'll be calling you a troll, and then debating with facts. Even at that extreme I'll defend you (while point out to people its probably a trolling exercise). I've defended the rights of trolls for years.. they help with the education process.

 

MPG doesn't inform you how many GALLONS were actually consumed, which makes comparisons extremely misleading. There is no indication of sample size either.

Not only doesn't that inform you how many KWH were actually consumed, that muliplier doesn't include real-world factors like temperature, speed, wind, traffic, passengers, cargo, etc.
.

 

Seem to be a disconnect here. Earlier you said you wanted

Gallons per distance, which is what you said you wanted, does not say how many gallons used either.

Pure Gallons/kWh used is useless for comparison as it depends on how much the person drives and they also don't include real world factors like temp, speed, wind, traffic. If you want all the factors then you want a multi-dimensional surface of efficiency vs the many parameters, i.e a BSFC like chart on steroids). I have no problem with 10dimensional functions for optimization problems, but good luck getting people to understand that.


I agree sample size is a problem, but until cars can all auto-report it will continue to be a problem.

 

You provide a quantity and a distance. For example, my Prius used 1,061 gallons to travel 53,264 miles. How can that be misunderstood?
.

The request was to simply add KWH to the GALLONS for whatever distance you are reporting. It tells others how much you've spent on fuel.
.

 

This estimated (by who?) .54 efficiency losses does it include upstream losses?

BTW, your signature says "86 mpg(e) for last 90 days", I suspect it is 90 days before Halloween (your last fill-up) isn't it?
If so, it's a bit misleading as last 90 days were mostly winter.

 

Reporting collected data avoids all assumptions and bias.

You can also include conversions.
.

Huh? Knowing the KWH quantity allows the person to apply their own rate.

We've been doing this for over a decade with GALLONS, knowing the price of gas would inevitably go up later.
.

 

The .54 was my estimate and includes upstream for fossil fuel, but not for renewables (not sure what upstream means for other). The upstream for fossil and oil refining does not include building the plants.. just the fuel upstream energy costs which for renewables is none.
For nuclear I never found a good direct estimate of energy used to produce the fuel for reactors, but estimated it using 15-65 gCo2/kWh from full lifecycle analysis (from Fthenakis, Vasilis, Kim, Hyung Chul, 2007. Greenhouse-gas emissions from solar electric- and nuclear power: a life-cycle study. Energy Policy 35, 2549–2557.) I'm putting this into a paper that I expect to publish later this year.

There are anti-nuclear and anti-renewable folks that look to define efficiencies in terms of theoretical potential (so nuclear is only 33%, wind 35%, etc..), and then argue they are more efficient than coal/gas plants. However, I believe its best done interms of fossil fuel burned.




The 90 days in my signature was 9/21 to 12/21, my last estimate when I updated my signature to remove my old "fuely" image (which was annoying others and way out of date by then..). Measuring gas does not take a fill up as the voltstats.net data show gas in tank accurately.

You are right I should update it and put in dates so its clear..
Done..

 

I disagree, KW pricing is too complex for a single number to convey price. In CA it depends on your tier (how much other energy you use) and time of day when you use it. And real costs should include infrastructure and other costs. Almost no one that does not already own an EV can/will figure out the rates, and even many EV owners have a hard time.

But to satisfy your sense of appropriateness, I've updated my signature to include what you asked as well as what I think people really want to know.

 

I think if there is enough demand, infrastructure will come up to meet the demand.

I expect utilities to get in to the game in a big way to "grow" their business.

 

Yes - what I meant was, 3 hours driving - 15 minutes recharge for the same price as an ICE now costs.