How will the Chevrolet Volt be better than a Toyota Prius plug-in hybrid?

I guess it is difficult to obtain the recent data huh? I agree, that's how government works. At least, EPA is coming up with a way to truly compare the carbon footprint between gas only (hybrids included) vs. plugin cars (two or more fuel sources) with the beyond tailpipe emission calculator.

The data may be 5 years old but it is better (more accurate) than ignoring the fuel production emission/efficiency and simply focus on EPA vehicle efficiency.

We produce about a third of oil we consume. I would think if we consume coal at the rate of we do of oil, we'll probably need to import as well. We need to diversify energy sources which plugin vehicles are the key to achieve it. I also think the key to succeed is to get there honestly and with integrity -- else there will be backlash.

Prius PHV is a perfect example of a carefully crafted plugin balancing out all the benefits and drawbacks.

It is news to me. Do you have a link/source?

 

Here is a recent study done by Argonne National Lab that also shows that there is no synergy between wind and coal.

Grid realities cancel out some of wind power’s carbon savings | Argonne National Laboratory

Another reason to focus on the grid average.

 

Volt copied it straight from TRW hybrid design.

Both Toyota and Ford hybrids have the input and output in reverse of TRW / Volt design.

 

13kW at 62mph for Prius sounds about right.

Yes, Prius PHV should get 130-140 MPGe if it is driving with just the electricity. Remember, this is only vehicle efficiency regardless of fuel production. Blending in with gas would drag the vehicle efficiency (MPGe) down. However, Prius PHV was designed to optimize beyond tailpipe emission, not just vehicle efficiency.

 

Do you bother to actuall read the articles.. or just the headlines.
The study does NOT show "No synergy", they don't even discuss synergy. (I would, however, agree there is no synergy, because the word means a combination that is more than the sum of its parts, and there is no reason to expect synergy in the grid).

Though your final statement is more about the overall emissions in the grid, not synergy, so let's look at that.

Here is their chart on CO2 production as wind is added.


The article concludes:

The point of the article, which is was generally known/accepted, is that if you add 100MW of wind, you don't quite get 100MW of savings of Coal CO2 production. The study is a simulation to help quantify the actual gain, as you add more wind. Its also important to note that their other article address how to use predictive forcasting to reduce the thermal cycle losses.

 

Perhaps I didn't state it well. We both are saying the same thing.

Wind does lower the CO2 output despite the additional inefficiency it introduced to the coal plants.

Therefore, I reinforced the idea of using the collective grid CO2 average rather than focusing on the green power cert you are supporting.

 

Which patent/trw design are you saying the volt matches? Please provide a citation.

I've stuidied many and the closest to the HSD or the Volt is
Patent US3861484 - HYBRID VEHICULAR POWER SYSTEM - Google Patents
but neither volt or HSD are a direct mapping of that design --- there are lots of ways to reconfigure what is where in an epicyclic design.

 

Yes wind, when used in large quantities does not have a 1-1 reduction in carbon.. (note the paper is looking at what happens with wind is in very high total percentage. In smaller quantaties, say under 20%, its nearly linear and almost 1-1. But one adds wind in the 30-40% of total load range it can cause places that use coal to become less efficient. The paper is more about what can happen when wind gets that much.. right now its much lower. Colorado is only at 9%, though we have goals for 20%.

As I said, the paper was showing that as wind penetration grows it could be a problem and in their second article, they show how using predictive controls can address much of that.

Nothing in either of their papers says to use the grid average for an individual's impact.

 

I lost the link to the source that said TRW design had the input/output in reverse of HSD. I had assumed that since Volt has the input/output in reverse of HSD as well, TRW and Volt must be the same. I searched for it again and found a different source.


It describes exactly how TRW hybrid connected to the planetary gearset:


– ICE drives the planetary SUN gear
– The “speeder” (generator) M/G connects to the carrier
– The “torquer” (motor) M/G is connected to the ring gear via an
additional gear ratio.
– Ring gear output shaft transmits summation power to the vehicle
driveline.

Comparing with MT illustration of Prius and Volt (below). The input/output of TRW design matches that of the Volt. However, the component arrangement is different.

So why did you knowing bashed Toyota and accused Prius of "copying" the TRW design?

 

You cannot make claim of reducing your carbon footprint by that amount of electricity you used in your Volt.

See #7:

As pointed already, the amount of wind electricity pumped into the grid does not equal the carbon saving due to the inefficiency introduced.

You are doing a direct claim. You need to claim to indirect emissions.

#10 suggests you use the subregion emission from eGRID. It is the same data the Beyond Tailpipe Emission calculator uses. For Colorado, that's 330 g/mi with renewable included.

 

The TRW is not exactly the same as either the Prius of the VOlt.

The ICE in the Volt is on the ring gear, the drive shaft is on the planet carrier. For charging, the volt does not split the ICE via the epicyclic gears with the sun turning backwards, rather it has a direct couple between the ICE and the generator which is then coupled with the ring gear. The ICE is not directly (only indirectly via the generator) connected, which is important if it is going to support series mode.

The prius design is more similar to the TRW in that the Prius design has the "torquer" () connected via added gearing between the ring, MG and the drive train. The prius design, like the TRW, uses negative splits from the ICE into MG1 to go battery recharge as well as obtain the The only PRIUS vs TRW difference is the switching of the ICE to the carrier vs the sun.

Both are different from TRW, its just that the Prius is closer. But I was not trying to bash Toyota, I made the comment in response to a post by Telmo that said the Volt copied the Prius.. and I was saying the prius design was just as much "copied" (in the way telmo used the term) from the TRW.

 

Point well takened.

Thank you,

DBCassidy

 

First of all EPA Claim Guideline #7 makes it clear you CAN claim to be reducing your footprint it that paragraph ends with

I did not make a direct emission claim, it was all indirect

Here is the post/claim I made

Clearly my claim was not direct, it was alway indirect in that I was talking about buying green energy and renewable generation. You were talking about "upstream" emissions which are, by definition, indirect. I replied in kind. Direct emissions are those my vehicle makes on its own. Which is Zero for the battery but not for the ice.

You are misunderstanding the point of #10 in the claims table. It is explicitly saying to "Use Emissions & Generation Resources Integrated Database (eGRID) utility subregion emissions rates when calculating carbon equivalencies." That is, it is saying that to estimate much carbon savings I can claim, if I want to claim I've reduced my carbon footprint by XX tons of CO2, then I need to compare the CO2 in my area. By buying renewable green energy in CO I can say, by those guidelines, something like I'm reducing the indirect carbon generation by 330g/mile.


BTW, you may notice that in my original post on what my upstream was I used 15% efficiency in terms of fossil fuel. I used a much larger number than would be true for 100% wind, which uses no fossil fuel except in manufacturing, because I realize there are increase efficiency losses in the grid because of the way wind must be integrated (i.e. I already accounted for the type of losses you were trying to get at in some of your previous posts).[/quote][/quote]

 

eGRID2012 is now available with 2009 data. However, Beyond Tailpipe Emission calculator has not been updated to use eGRID2012 data. It should be updated shortly, hopefully.

I compared the US total CO2e from 2007 and 2009 data (p.1 table).

2007 Total output emission of Carbon dioxide equivalent (CO2+CH4+N2O): 1,299.66 lbs/MWh
2009 Total output emission of Carbon dioxide equivalent (CO2+CH4+N2O): 1,222.29 lbs/MWh

The improvement is 6.3%. 2009 data translates to 554.4 gram of CO2e per kWh generated. Which means driving Volt on pure electricity would emit 204.3 g/mi. That's an improvement over 217.3 g/mi from 2007 data.

Volt's gas miles will remain the same at 299 g/mi. The composite of gas and electric should improve slightly from the current 260 g/mi. I would guess 250 g/mi the best case -- which is still higher than 50 MPG no-plug Prius at 222 g/mi.

Hopefully eGRID2013 would have 2012 data. I am still waiting for EPA to add Prius PHV numbers in the Beyond Tailpipe Emission calculator.

 

Since we are talking about power-split transmission history again, here is a link to an earlier thread where I pointed out that Toyota's HSD is essentially identical to a design described in a GM patent covering clutch-less one mode input-split transmissions way back in 1995 before Toyota filed their first HSD patents in the U.S. and before the original Japanese Prius came out in 1997.

Does GM REALLY want to phase out the Volt? | Page 9 | PriusChat

So, one could say that Toyota "copied" the design covered in GM's patent. It's interesting that GM chose not to sue Toyota and, obviously, Toyota never approached GM as they did with Ford even though the input-split idea is embodied as a subset of the two-mode GM transmission which was first sold in 2003 for busses and large trucks and later adapted for SUVs and pickups.

Back then, GM was just not serious about competing in the small car market in the U.S. and I believe hybrids were slow to be adopted in Europe. Now that GM is getting serious about mid-size and smaller cars again (Cruze etc.) I fully expect GM to come out with a one mode HSD-like transmission since a two-mode is unnecessarily complex and expensive for smaller cars.

 

Limit claims to indirect emissions. Your organization should be careful when making claims of emissions reductions. If you are buying renewable electricity or RECs, you are reducing your indirect emissions. Indirect emissions are those resulting from electricity generation that an organization buys from an electricity service provider. An organization buying green power can claim to be reducing its carbon footprint, but cannot claim to be reducing its total emissions to the atmosphere.​

All this is saying is that you can't claim the RECs for lowering your direct emissions, like generators and vehicles. It is also a lead in to #8, where it covers that a REC may not include other cap and trade pollutants, like NOx.​

 

That part about pollutants is very important and left out of most analysis. Where cap and trade policies exist, NOx, SO2, and particulate emissions are not decreased by renewables, or increased by electricity demand except in rare cases. These pollutants are dependant on the cap and other regulations instead. Using more non-renewables means more pollution control devices must be paid for or heavily polluting plants closed down. That is why in these states using renewables does nothing to reduce the unhealthy electrical emissions, and using more power does not increase them. Power source choice does change use of fossil fuels and ghg.

 

I love the new "ignore" function on this site. Once activated it's like the poster never existed.

 

Yes, Interestingly it even removed their quoted text.. I was confused by your post for a second.. had to unignore (I was guessing you meant DB, but was not sure) to see if that is what you meant (and if you were ignoring me;-)


But ignored folks are still are mentioned in likes.

 

Me too! It is a nice feature

DBCassidy