Shocking : Tesla Model S gets 26.5 mpg

In CA, the state publishes data submitted by oil companies, among other entities, about how much natural gas (and coal, but that's kind of rare) is used for onsite co-generation. As far as I can tell, the oil companies used to include info on how much of the natural gas was dedicated to onsite operations (all steam/some electricity), and how much was exported to utilities (remaining electricity), which is how the state could publish information on how much natural gas was used in oil extraction. The total output of the co-generation plants is still published, but the amount that's exported to the grid isn't, at least as far as I can tell. This makes it impossible to determine how much natural gas is currently used for oil extraction. I'm also not sure if this accounts for all nat gas used on site, or just when it's used for sufficiently large (MW+?) co-generation.

 

That's spot it. It's something like ~1kWh of electricity, and enough natural gas to generate another ~4kWh of electricity in a CC plant.

The accurate statement would be "The electricity and natural gas used to make a gallon of gasoline could also provide ~5kWh (or w/e the specifics are) of electricity."

 

...possibly, uncertified, and for one of the most, if not THE most, highly energy intensive refinery in the USA, after assigning to the refinery upstream energy debits before the refinery even received the crude oil. Probably assuming 100% conversion of upstream natural gas BTU heat value into kWhrs. Probably for the worst day if the year.

On this basis there might be a smidgen of truth. But the number is usually quoted as the amount of electricity each refinery in the USA consumes.

The truth is refineries use a tiny amount of electricity, with a few California outliers possible. Nobody sits around and calculates kWhr per gallon because its such a tiny number. As soon as we start talking Kwhr per gallon it's just automatically something an environmentalist concocted to make a political (and probably non-truthful) point.

 

We are far from the right thread for this but here is a energystar report on electricity and ghg from other sources at the refineries on page 22 and 27

http://www.energystar.gov/sites/default/files/tools/ENERGY_STAR_Guide_Petroleum_Refineries_20150330.pdf

The figure shows that the main fuels contributing to the emission of CO2 are still gas, natural gas and coke. Still gas comes with the oil, but can be separated and sold as propane, butane and its other constiuants, but its cheaper to burn some of this than sell it and buy more natural gas. The coke is a waste product similar to sulfur coal, which needs to get burned, burried, or exported to countries that don't care about the sulfur (either good scrubbers on coal power plants, or lots of sulfur pollution. Only the natural gas and electricity could really be used elsewhere.

 

Nice find! I never though to look for EnergyStar reports on refineries. Dishwashers and refrigerators, yes, but refineries?

It's a long report do I have to read through it over the weekend

You make a good point that of all the process fuel inputs to refining the only parts that would be available for EV charging if we stopped refining gasoline would be the natural gas, steam, hydrogen, purchased grid power, and coal. All of that makes up less than half of the energy being used in refining gasoline.

Convert the rest into electricity at 50% conversion overhead (best case) and your talking 1.25 - 1.5 kWh of electricity or thereabouts per gallon of gasoline manufactured to power an EV instead of powering an ICE. In order to crank that up to the 5 kWh being claimed you would need to get or generate another 3.5 kWh or so of electricity.

I'm very dubious that you can get that from looking at extraction (in)efficiency or distribution much less keep the combined total upstream CO2 emissions in alignment with the 5 pounds estimated by GREET.

I know less about typical or average extraction energy and energy sources than I do about refining. I will have to spend some quality time learning more about that in the next few days

So far I remain doubtful about the overall case that roflwaffle is cooking up.

 

That's accurate, but it's not the whole story. Refining and extraction are where the energy come from. And the electricity/steam used in extraction is more energy intensive than what's required for refining (I wanna say it's 70/30 extraction/refining).

 

Check my math but if it took 7 kw per gallon that means a big TX refinery would need 3 x 1200 MW nuke reactors to run.

 

According to this source;
Big Spring Refinery | alonusa.com
Big Spring refinery in Texas does 73,000 barrels per day. Times 340 days/year (leaves a few weeks out for maintenance) - that's nearly 25 million gallons/year. Presuming 7kWh's per gallon (of energy), that'd be 175 million kWh's ... or, per hour, 22,000 kW's constant energy necessary to make all petro-goodies ... or put anorher way - roughly 400x more than many home's maximum 'energy' draw? That doesn't seem too far fetched, but it's way past my bed time - so check my math.
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That's likely CA specific b/c we have so much heavy crude that requires a lot of steam to get flowing and a lot of electricity to pump out, which is why there's a lot of co-generation. We don't have big nuclear reactors, just big natural gas plants.

To help assuage your doubts, Check out the GREET breakdown for gasoline (E10) energy content. Nat gas is a little less than 20% of petro energy inputs. Which puts it at ~5.8kWh/gallon of E10, and ~2.6kWh of electricity delivered to a consumer's home using yearly CC averages (45%) for CA nat gas plant efficiency (I think 50% is a bit high). The greet model also includes coal, which would provide another ~.25kWh in a lower efficiency coal plant.

Now, the kicker is, those are just FF inputs for E10. I imagine refineries, and maybe extraction ops to a lesser extent, use electricity generated by nuclear/renewables, which aren't included in the GREET model. I emailed to confirm, but my guess is that even at the national level, ~2.9kWh/gallon of electricity from the ~6.6kWh of FF energy inputs isn't the whole story b/c GREET doesn't look at renewable/nuclear inputs, just at FF inputs.

And, like I've said before, since CA extracts so much heavy crude, ~4kWh/gallon for nat gas is accurate, which has been supported by data publish by the state. On top of that, CA RFG has ~10+% less energy than E10, but uses something like 98% of the natural gas, so even if it doesn't use more natural gas in absolute amounts, a gallon of RFG doesn't move a car as far as a gallon of E10, which further skews things.

When compared to regular unleaded gas (RUG), my guess is that the nat gas/electricity/coal (in some places) used could also generate enough electricity to move an EV ~10+ to ~20+ miles depending on the EV and type of gasoline.

 

OK but 73000 is like really small player in TX I am thinking we got some 300,000 barrel per day gasoline joints out there.

 

I feel like we have gotten off topic here. I started a new one for refinery energy here.
Refinery energy consumption | PriusChat

It looks like in 2010 refineries purchased 44 TWh of electricity, and used 62 TWh, generating the difference on site.

 

My impression is that any real disagreements at this point are about oil extraction rather than refineries. And, more specifically, how much electricity could you generate for use in charging an EV if you chose not to extract the oil and refine a gallon of gasoline.

As far I can see, everyone is agreeing that grid electricity use by refineries is quite small and is in the range of 0.2 - 0.3 kWh per gallon or thereabouts.

 

It's mainly an issue because some, not all, EV activists like to misquote the info as use is as a weapon to argue in favor of EV's. Nissan actually used it in their first Leaf brochures, but quickly yanked it out of there. Usually the info is used incorrectly, and I should just let the activists go off into technical la la land. It only hurts the cause to exaggerate.

 

It is really low for eagleford or bakkan fracked oil, but very high for oil sands production. Oil sands may reduce production with the now very lower oil prices, but here we have mining to gas station of about 13 kwh / gallon if all the natural gas was turned into electricity. Lots of good number here, and it assumes lower keystone energy values, it costs more to truck and train the syn oil as we do now.
The Oil Sands’ Surprising New Nemesis: Plug-in Vehicles - HybridCars.com

 

I think the CA figures were ~.5kWh, but more or less I think everyone's on the same page.

The thing is, portraying all the energy inputs of gasoline as just the electricity refineries use is a straw-man if someone is comparing EVs to conventional cars.

In that case, you would need to look at all the energy inputs for gasoline, which includes electricity/nat gas for extraction and electricity/nat gas for refining.

 

I think you've hit the nail on the head. It's not just that Nissan used only refining, assuming they did, but that everyone jumped on that as inaccurate, which is OK, and then ignored how much energy is used everywhere else, which is not OK.

If someone at Nissan had just said "produce" instead of "refine" and focused on how much electricity could be delivered to a consumer's home, they'd be right. Maybe a little high, but at least ballpark.

 

It's interesting to see the (huge) difference between upstream CO2 emissions for conventional oil vs. oil sands but to understand the big picture we should use average values for extraction and refining.

I'm still looking but I've found some interesting but slightly dated US national data. Here's a breakdown for 2005 of the global warming gas emission from each stage between extraction (#1), transportation to the refinery (#2), refining (#3), transportation to the pump (#4), direct use in a vehicle engine (#5).

The bottom line is that emissions during refining for gasoline are slightly greater than further upstream extraction and transportation emissions. Overall, the emissions are roughly consistent with the GREET numbers I cited earlier for direct use of gasoline vs upstream emissions:

http://www.netl.doe.gov/energy-analyses/pubs/PetrRefGHGEmiss_ImportSourceSpecific1.pdf

 

Here's a breakdown for the energy use used in oil extraction circa 1997 by one of the leading academic experts. Newer data is unfortunately hidden behind a paywall.

It looks like 70-75% of the energy comes from natural gas but it isn't clear how much of that gas is purchased vs being extracted from the well along with the crude oil.

California's oil extraction appears to be more energy intensive than the national average but that's not surprising since a very large percentage of the active California wells are in old oil fields that have been pumped dry over decades. I saw a statistic somewhere that over 59% of California wells are producing less than 10 barrels a day.

Looked at in context with the global warming emissions table I just posted, it seems clear that at least in 1997 the electricity use in oil extraction was quite small per gallon of gasoline -- maybe another 0.5 - 0.75 kWh per gallon?

[ignore the weird link title...]
Download Limit Exceeded

 

What's the article title? I might be able to access it.

 

I don't recall offhand. I think it was a newer paper by Cutler Cleveland.