Volt 2.0: Ruess "It will leap-frog... the competition"

Although, obviously, the typical use case for the 2016 Volt is to use the engine no more than 10-20% of the miles driven. The rest is on US average electricity at a carbon equivalent of 54 mpg gasoline. Or, usually even better when driven in the many areas with lower carbon grid power, with optional utility renewable power, or with rooftop solar. The Volt, as an electric plugin, can efficiently use renewable energy sources unlike the CT200h or even the Mirai in many cases today.

 

That's not clear. The fueleconomy.gov emissions calculations are based on eGRID2012 V1.0 which is actually based on 2009 emissions reports. California renewable generation has been growing rapidly since then. One projection said that renewable electricity generation would approximately double in California between 2009 and 2015.

It's quite possible that the fueleconomy.gov full upstream combined gas+electric emissions based on battery size EPA Utility Factors adjustments would show the same or lower California CO2 emissions for a 2016 Volt as a 2016 Mirai using H2 from steam reformed natural gas plus 33% renewable H2. The Volt will likely be about the same or lower CO2 emissions by 2020 when the 33% renewable electricity target is reach and then grows to 50% in 2030.

For example, the 2013 NREL H2 pathways study says about 250 g CO2 per mile for 100% steam reformed H2 on a 67 MPGe fuel cell vehicle like the Mirai.

So, with 33% renewable it would be 250 * .67 or 167 g per mile. The 2016 Volt is also probably around 167 g per mile using the old eGRID numbers for California (130 g per mile in EV alone).

You like to use a Toyota graphic which implies 200 g CO2 per mile for a car like the Mirai. I don't think the detailed fueleconomy.gov numbers have been published yet for the Mirai (or the new Volt) so we have to guess in the interim.

If we assume that lower Toyota number, then it would be 200 g at 67% or about 135 g per mile (at state-funded H2 stations). Once the eGRID numbers catch up with actual 2020 California retail grid emissions it is quite possible that the 2016 Volt combined gas+electric emissions estimate will fall to about the same ~140 g per mile level.

When Mirai is fueled with 100% steam reformed NG H2, which it probably will be at non-state CA stations or at stations at other states, it will likely emit higher CO2 than today's fueleconomy.gov 2016 Volt gas+electric emissions of ~215 g per mile on US average electricity and those Volt results will continuously get better as the national grid cleans up and as the eGRID emissions database catches up to actual same-year emissions.

 

The US Congress failed to renew the law which gave fuel cell vehicles an $8,000 credit so the law automatically expired. The $7,500 battery credit is covered by a different law.

Mirai still qualifies for a $5,000 rebate in California along with the $2,500 state rebate for BEVs or $1,500 rebate for PHEVs.

Automakers Face New Challenge as Fuel Cell Car Tax Credit Dies | Edmunds.com

 

Thanks for the link, I hadn't read that article before.

That graphic isn't terribly helpful because it doesn't tell us what kind of H2 is assumed for the Mirai (100% H2 from NG, or with 33% renewables?) and it doesn't tell us what model year Volt is being considered and what efficiency is assumed for it (the article was before GM's final 2016 Volt EPA numbers). It also doesn't tell us what electricity emissions are assumed.

I'm looking around to see if I can clarify what data the LA Times graphic is actually based on.

 

The answer is.... The Mirai result shown in the LA Times graphic assumes 46% renewable H2 and the Volt result is based on the 2015 model year. CA electricity is assumed using eGRID.

If this chart were redone with 33% renewable H2 and the 2016 Volt EPA estimates then the numbers would presumably be substantially different even without adjusting the California electricity CO2 emissions to match this year's actual emissions instead of the emissions from several years ago.

 

The 2016 Volt tailpipe plus upstream emissions have just been added to fueleconomy.gov today. They are consistent with my earlier predictions on this thread here:

Volt 2.0: Ruess "It will leap-frog... the competition"

And here:
Volt 2.0: Ruess "It will leap-frog... the competition"

Here's a comparison chart for CO2 grams per mile for the California and U.S. average grid electricity (based on 2009 data) plus EPA gasoline estimates. The Prius PHEV and the Volts have CO2 estimates based on their SAE/EPA Utility Factor which is an estimate of the typical mix of electric versus gasoline miles based on the vehicle's battery EV range -- bigger batteries result in a smaller ratio of gasoline engine use. The Utility Factor estimates have been derived from and validated against real-world driving patterns.

CA US city/combined/highway
230 270 40/38/36 2016 Fusion Energi
218 218 51/48/50 2015 Prius
200 220 51/49/50 2015 Prius PHEV
180 250 35/37/40 2015 Volt
160 220 43/42/42 2016 Volt
140 200 xx/39/xx 2015 BMW i3 REX

Note that the 2016 Volt now has the same national average CO2 emissions estimate as the Prius PHEV.

 

Okay. I'm waiting....

 

Dennis was implicitly referring to CO2 when he wrote "clean" consistent with some of his earlier postings. I called that out specifically in a reply post on this thread and he did not disagree that CO2 upstream emissions were the "clean" target he was referring to.

In any case, tailpipe plus upstream CO2 emissions are the only detailed calculated comparison available to us on fueleconomy.gov for vehicles that mix gasoline and electric energy sources.

 

Huh? The numbers I listed are hybrid-mode gasoline mpgs and they are correct.

Perhaps you are thinking of the 2016 Volt's EV range.

 

Mirai on NG H2 is probably around 210-215 g per mile using combined EPA and UCS estimates. I don't see any upstream emissions estimates for Mirai on fueleconomy.gov yet.

So, on NG H2 the Mirai might be 2-5% lower CO2 than the 2016 Volt on a Utility Factor mix of US average grid plus gasoline.

However, we should keep in mind that the average grid CO2 emissions data is 6 years old and in the meantime the national average coal use in the grid has been plunging. Back then in 2009, coal made up 45% of the fuel mix for the U.S. grid. As of spring 2015, coal's fuel mix percentage on the U.S. grid has now dropped to 30%.

See:
SNL Mobile: Data Dispatch

So, the 2016 Volt's actual national CO2 emissions today are probably significantly lower than the 220 g per mile reported by fueleconomy.gov.

Mirai on 33% renewable plus NG H2 in California (as required by state regulations in state-funded H2 stations) would therefore likely get around 142 g per mile at best (using UCS estimates) versus the 2016 Volt's 160 g per mile estimate on CA grid electricity plus Utility Factor gasoline use.

So, Mirai might be 11% or so lower CO2 on that comparison. But again, those underlying CA grid numbers are 6 years old and renewable grid levels have been dramatically improving since then -- from about 15% to 25% with a target of 33% by 2020 so the 2016 Volt in CA might be not far from the Mirai's CA ~142 g per mile today.

At the moment, CA-funded H2 stations are initially projected to have 45% renewable H2 (so, more than required). But, if a Volt is driven more on EV than the EPA estimate or is charged up with higher renewable electricity than the average CA grid then the 2016 Volt might easily match or improve on the Mirai's emissions at 45% renewable.

Basically, the 2016 Volt is roughly equivalent on CO2 emissions with the Mirai nationally on mostly NG H2 and in California within the next few years with 33-45% renewable H2. Yet the Mirai costs almost twice as much, requires a lot of new and expensive refueling infrastructure, and the H2 itself is more expensive per mile driven.