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No Longer Just A Toy For The Rich!

Is it REALLY for everyone?

Check out the last paragraph, genius or crazy, would you use this?

http://www.telegraph.co.uk/motoring/green-motoring/10889737/I-bought-a-T...

Go Robin Hood!!

I wonder if he really has ordered 30 Model S cars for his limo service? Sounds like a cool service he plans to offer - much nicer than being picked up in an old town car.

Found this interesting youtube in the comments section...
https://www.youtube.com/watch?v=BQpX-9OyEr4
relates to how much electricity is used to refine oil.

Correct me if I am wrong but is not 4.5 KWHr of electricity roughly 15 miles in my MS? If it is, it would seem refining gas chews up just about all the mileage an average car gets from a gallon of gas. This number does not seem right/reasonable.

They try to say it balances out because more than just gasoline is produced from the refining of crude oil... Natural gas, Diesel, Kerosene, Gasoline, precursors for plastics, and a whole range of lubricant materials. Remember, gasoline wasn't chosen to power vehicles because it was the best solution. It was chosen because it was an unwanted throwaway byproduct of refining oil, considered dangerous waste, and was thereby cheap to use. The automotive industry just made the best of what they had to work with... and have been forever tied to the petroleum industry ever since.

Interesting that the average car uses 500 gallons of gas per year and that takes 2,250 KW of power to make
(4.5 KW/gal X 500=2,250KW)! That is about 8,000 miles for the MS(2,250/85x306). If the 4.5 KW of power used per gallon of gasoline is correct, the argument that electric cars are just coal burners is completely invalid!
Because the MS is so much more efficient than burning gas it starts to look possible this is correct.

There is a lot of heat used in the cracking process and electricity is the only safe source of heat given the volatility of the environment I suspect. Perhaps some one here is well informed on the cracking process.

Seems within the realm of possibility for me!

I think the net reality of it is what is important. What does the refining industry look like when there is less demand for gas? Is 4.5KWHr of power saved for every gallon not used? Can a less refined oil product destined for gas be used to displace electric power (safety concerns aside)?

I kinda wish there was an unassailable buried resource to mile driven comparison. The problem with discussions are that different agendas use different facts. I've learned not to crap where I sleep which I guess puts me in the environmental camp for those that need to label. I really do not care for labels and simply strive to understand the facts so that I can take reasonable position.

About 0.1-0.2 kWh of electricity is used to refine a gallon of gasoline from oil. The 4-7 kWh per gallon numbers commonly cited refer to total energy, not just the small subset that is electricity. The vast majority of energy used to refine oil is thermal, and comes from burning byproducts from oil refining (from the oil itself) and burning natural gas.

The report we saw was from England and may not be the same energy sources for heating as in North America. Either way the amount of energy coming from oil byproducts is more likely less friendly to the environment than electricity since at least some comes from hydro and nuclear. We need some expert analysis, there may be some useful information for counter acting the claims of the anti electric car lobby.

I'm a chemical engineer who works in oil refining. I also own a Tesla Model S and offset most my home and EV electric power use with rooftop solar PV.

The video made in England repeated the same false claim about 4.5 kWh of electricity to refine a gallon of gasoline that one often sees in the US. Except sometimes the claim is 6.5 or 7.5 kWh of electricity per gallon. This mistake is made because most people see kWh and automatically assume it's electricity. In fact kWh is a unit of energy, and energy comes in forms other than electricity.

Most energy consumed in oil refineries comes from burning petroleum coke and light hydrocarbon gases that are byproducts of oil refining conversion processes -- these fuels are derived from petroleum. The next largest source of energy used in oil refining is natural gas that is burned. Oil refineries have many furnaces (you can see the stacks) producing the thermal energy required to operate refinery processes. The amount of thermal energy produced in those furnaces dwarfs the amount of electricity consumed.

Natural gas is also used to make hydrogen through steam-methane reforming. Hydrogen is consumed in hydrotreating and hydrocracking processes in oil refineries.

The electricity used in oil refining is about 0.1-0.2 kWh per gallon. Many oil refineries produce their own electricity with on-site co-generation plants.

Thanks for that, CalDreamin!

CalDreaming, If you used the energy being consumed to refine crude oil how much electricity could be made with the same amount of fuel. Seems sort of silly to not consider fuel being burned as an energy cost of making the fuel. Energy is energy. So how much energy is used to create gasoline as an energy source.

If you are looking at cradle to grave energy use it doesn't matter if the fossil fuel is burned to create the heat or burned to create the electricity to then create the heat. It takes energy to refine oil. Where the energy comes from is just a process question.

I always thought that this was the obvious advantage of EVs.

Its not a trade off between oil and coal.

Its the fact that EVs use 75% less energy to run.

Hence an EV in West Virginia run on 96% coal still has less emissions than a standard ICE engine.

If oil refineries weren't operating, some but not all of the energy used to refine crude oil would become available to make electricity.

Much of the energy used by oil refineries is made from burning byproducts of oil refining. The energy from the petroleum coke and light hydrocarbon gases that refineries make and burn would not be available for other purposes. This would still be tied up in the crude oil, and buried underground.

The purchased electricity and the natural gas that refineries consume would become available if refineries weren't using them.

Annual EIA stats for all oil refineries in the US (2012)
Purchased electricity = 44,635 million kWh
Natural gas = 843,228 million ft3
http://www.eia.gov/dnav/pet/pet_pnp_capfuel_dcu_nus_a.htm

The EIA says that 127 kWh electricity is produced per 1000 ft3 of natural gas (on average)
http://www.eia.gov/tools/faqs/faq.cfm?id=667&t=2

So 107,090 million kWh of electricity per year could be made from the natural gas that refineries otherwise consume, in addition to the 44,635 million kWh of electricity refineries purchase each year.

@CalDreamin, are you saying that the 4.5 KW is wrong amount or that only a small part of the 4.5 comes from electricity?

If 4.5 KW is reasonable estimate of the amount energy needed to make a gallon of gasoline then it is a moot point whether the energy is produced with electricity or burning fossil byproducts. A lot of CO2 is generated creating the energy to make gasoline which then is burned at an annual average of 500 gallons per vehicle which generates about 9,000 pounds of CO2. The question I am trying to get an answer to is how much CO2 per gallon of gas is generated just to make it. We have a god idea what is generated when it is burned. We need to add them together to get actual CO2 emissions from automobiles. And this does not include the gas burned in order to deliver all that fuel through the distribution system.

Perhaps someone like you could develop a CO2 estimate per gallon during manufacture and someone might know something about distribution, and numbers are already available for light vehicle CO2 emission. So we just need to add it up. Might surprise everyone!

EdwardG, somewhere around 4.5 - 7.5 kWh per gallon is the right number for total energy consumed, but electricity is only a small part of that.

EPA has the stats you are looking for on their http://www.fueleconomy.gov/ website. When looking up an ICE car, select the Energy & Environment tab and then under Greenhouse Gas Emissions select Tailpipe and Upstream GHG. The upstream component covers the production and refining of oil, and distribution of gasoline. Tailpipe and Upstream combined is the well-to-wheels GHG emissions.

2014 Prius
179 g/mile CO2 (tailpipe)
43 g/mile CO2 (upstream)
222 g/mile CO2 (tailpipe + upstream)

2014 BMW M5
554 g/mile CO2 (tailpipe)
138 g/mile CO2 (upstream)
692 g/mile CO2 (tailpipe + upstream)

http://www.fueleconomy.gov/feg/Find.do?action=sbs&id=34489&id=33662&#tab2

In both cases the upstream CO2 is 24-25% of tailpipe CO2.

For EVs, the fueleconomy website directs you to another page where you need to enter a zip code so it can look up regional grid CO2 emissions per kWh of electricity.

2014 Tesla Model S 85
250 g/mile CO2, U.S. average grid (tailpipe + upstream)
150 g/mile CO2, California average grid (tailpipe + upstream)
http://www.fueleconomy.gov/feg/Find.do?zipCode=94595&year=2014&vehicleId...

For those of us who have solar PV, on a net basis our well-to-wheels CO2 g/mile driving an EV can be a lot lower than the EPA calcs.

@CalDreamin, thanks for that info. I got the average (about 500 gal/yr and 9,000 pounds CO2 emissions)from the site but did not realize all that other great stuff was there. I assume the Tesla CO2 using the (tailpipe + upstream) is really only upstream. Can't be any attributed to tailpipe that I am aware of.

Thanks again!

E.G.

Since much of the energy is produced from byproducts of the refining process, it should be discounted, unless those byproducts would have been extracted and exploited anyway. They're "free", from the POV of the refining process itself.

@brian....sure they are free but burning them for heating produces CO2 which we are all trying to reduce. There is a lot of reasons to burn these by products but none of them are about reducing CO2 emissions. Just pointing out the argument that Electric Cars are just coal burners is folly! From above:

2014 BMW M5
554 g/mile CO2 (tailpipe)
138 g/mile CO2 (upstream)

As you can see this car has 25% of the CO2 (138/554) is from upstream (manufacture and delivery of gas) so the argument that about 30% of the electric car energy is from coal (depending on your grid) is Irrelevant. Most people won't know that the automobile fuel has a similar upstream CO2 footprint as electricity on many electric grids. In addition Tesla is 8 times more efficient using energy but haven't figured how that impacts the issue yet.

No, the CO2 issue is entirely bogus. The only documented effect to date is the greening of arid areas and significant increase in agricultural productivity. The century-long slow warmup after the Little Ice Age is actually slowing down. Hope it resumes.

No, Brian H is completely bogus; you can crap in your food and live a healthy life.

@brian, that kind of logic makes it pointless to discuss it with you!

It is better to state the 4.5-7.5Kwh of energy as "Equivalent emissions" since the fuel is still burned and creates emissions...

Also some of these refineries do not have to follow the strict emission guidelines of grid based power plants. Not all of them are as clean in what they burn to make the steam/heat to refine the fuel...

Brian H.... I believe that You are just wrong... Period...


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