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CA requires batteries to be warrantied for 10 years and 150k miles. Manufacturers will build them to exceed this requirement to avoid warranty claims. 200k miles seems like a reasonable expectation for the lifetime of a battery, or any car in general.
That is PZEV, not ZEV cars. The Bolt is 8 years 100,000 miles. However your 200,000 mile expectation is a lower limit IMO. There are plenty of Bolts well over 100,000 miles on their first battery going strong.
 
That might be, I'll need to run the numbers to see. We'll need to wait and see just how many miles a battery is typically used before a car is junked. It could be so, but it is yet to be seen, even though there are some high-mileage EVs around, we don't know yet what the typical case will be.
That might be????? It is EXACTLY what it is!!! The 150,000 km is already nonsense as many Bolts easily reached this number without large amounts of battery failure. Maybe if we were talking passively cooled Nissan Leafs I would agree with that 150,000 km number. I still don't agree with that 1 paper that says a battery takes between 150 kg to 300 kg (1 to 2 g / kWh / km for 150,000 km of battery lifespan) to make 1 kWh of battery. The average numbers are 70 kg to 110 kg (0.47 to 0.73 g / kWh / km for 150,000 km of battery lifespan) according to many sources. But you can't make your point using average data, you need to use that 1 paper for your argument. Below is data to show that the 150,000 km value is nonsense.


I am going to do your crazy calculation comparing your old Volt to a Hyundai Ioniq BEV using your calculation. You can't deny this :p

A lithium-ion car battery has a life cycle CO2 cost of about 1.5 g CO2 / kwh / km. (1)
The Hyundai Electric has a 28 kWh battery, so the CO2 cost is ~ 1.5g CO2 / kWh * 28 kWh / km * 1 km / 0.62 mi = 67.7 g CO2 / mi. = 0.0677 kg / mi.
The Volt has a 16 kWh battery, so the CO2 cost is ~ 1.5g CO2/kWh * 16 kWh / km * 1 km / 0.62 mi = 38.7 g CO2 / mi = 0.0387 kg / mi.

The Hyundai Electric has an MPGe of 136, or 25 kWh / 100 miles.
The Volt has an MPGe of 106, or 31 kWh / 100 miles.

For Oregon, the carbon intensity of electricity is ~ 0.11 kg / kWh. (2)

Hyundai Electric CO2 / 100 miles: 25 kWh / 100 mi * 0.11 kg / kWh + 0.0677 kg / mi * 100 mi = 9.52 kg / 100 miles.

Volt CO2 /100 miles
: I'm using your typical use of 66.5% EV mode. So, the Volt will travel 66.5 miles in EV mode and 33.5 miles in hybrid mode. EV mode CO2 cost is 31 kWh / 100 miles or 20.615 kWh / 66.5 miles * 0.11 kg CO2 / kWh = 2.26 kg CO2 / 66.5 miles for the electricity. The life-cycle battery cost is 100 mi *0.0387 kg / mi =3.87 kg. Then there will be 33.5 miles of hybrid mode at 42 miles / gal. So 33.5 miles / 42 mpg = ~0.8 gallons. 1 gal = 8.9 kg CO2 (3). so 33.5 miles produces 0.8 g * 8.9 kg = 7.12 kg CO2 / 33.5 miles. Total CO2 cost of 100 miles = 2.26 kg + 3.87 kg+ 7.12 kg = 13.25 kg / 100 miles.

Please let me know what I did wrong with your calculations? It seems that the Hyundai Electric wins by a lot.
 
For heavy use a BEV is superior, but people don't drive like me. I put 40,000 miles on my car every year. The longer you drive a BEV, the better it gets. In my situation a BEV is superior considering I drive in California, have solar panels, and have a 130 mile commute every day. For me a BEV is much better for the environment than a PHEV, please prove me wrong about my situation.
Just stating the obvious, but are you charging your car with energy stored from your solar? If not, and you are charging at night, then you really have to see where your night time energy is coming from...
 
I don't really trust any of these "well-to-wheels" calculations because they are very complex with answers strongly dependent on the assumptions. Imagine accounting for all the CO2 emissions produced by making a battery: extracting the raw materials, transporting, refining, transporting, processing, transporting, fabricating parts such as separators, case,...on and on. Then consider making an ice, the exhaust, and fuel delivery for a phev - extracting the iron ore, transporting, smelting, extracting the alloying elements, transporting...furnaces to make the steel...on and on. Many, many steps and highly variable depending on many factors. In such a case the result depends strongly on the assumptions used. If you don't sweat every detail of the calculation you don't know what the final number really represents. Beyond that, should you also account for the energy that went into (and the resulting emissions) building the factories that make the batteries and their parts, the engines and their parts? If so, how do you estimate a per unit cost in emissions? What assumptions do you use for total units that will be produced, and what effects that assumption? It goes on and on...
 
I don't really trust any of these "well-to-wheels" calculations because they are very complex with answers strongly dependent on the assumptions.
I think that the big benefit of these kinds of analyses is to remind us that it's not just driving efficiency that counts. But in terms of using them for comparison purposes - yeah, you've got to be very careful not to put more trust in them than they deserve.

The big takeaway is that, like any other vehicle or other manufactured object, driving or using it longer reduces the impact of the purchase cost and all of the harm caused in its manufacture.
 
That might be????? It is EXACTLY what it is!!! The 150,000 km is already nonsense as many Bolts easily reached this number without large amounts of battery failure. Maybe if we were talking passively cooled Nissan Leafs I would agree with that 150,000 km number. I still don't agree with that 1 paper that says a battery takes between 150 kg to 300 kg (1 to 2 g / kWh / km for 150,000 km of battery lifespan) to make 1 kWh of battery. The average numbers are 70 kg to 110 kg (0.47 to 0.73 g / kWh / km for 150,000 km of battery lifespan) according to many sources. But you can't make your point using average data, you need to use that 1 paper for your argument. Below is data to show that the 150,000 km value is nonsense.


I am going to do your crazy calculation comparing your old Volt to a Hyundai Ioniq BEV using your calculation. You can't deny this :p

A lithium-ion car battery has a life cycle CO2 cost of about 1.5 g CO2 / kwh / km. (1)
The Hyundai Electric has a 28 kWh battery, so the CO2 cost is ~ 1.5g CO2 / kWh * 28 kWh / km * 1 km / 0.62 mi = 67.7 g CO2 / mi. = 0.0677 kg / mi.
The Volt has a 16 kWh battery, so the CO2 cost is ~ 1.5g CO2/kWh * 16 kWh / km * 1 km / 0.62 mi = 38.7 g CO2 / mi = 0.0387 kg / mi.

The Hyundai Electric has an MPGe of 136, or 25 kWh / 100 miles.
The Volt has an MPGe of 106, or 31 kWh / 100 miles.

For Oregon, the carbon intensity of electricity is ~ 0.11 kg / kWh. (2)

Hyundai Electric CO2 / 100 miles: 25 kWh / 100 mi * 0.11 kg / kWh + 0.0677 kg / mi * 100 mi = 9.52 kg / 100 miles.

Volt CO2 /100 miles
: I'm using your typical use of 66.5% EV mode. So, the Volt will travel 66.5 miles in EV mode and 33.5 miles in hybrid mode. EV mode CO2 cost is 31 kWh / 100 miles or 20.615 kWh / 66.5 miles * 0.11 kg CO2 / kWh = 2.26 kg CO2 / 66.5 miles for the electricity. The life-cycle battery cost is 100 mi *0.0387 kg / mi =3.87 kg. Then there will be 33.5 miles of hybrid mode at 42 miles / gal. So 33.5 miles / 42 mpg = ~0.8 gallons. 1 gal = 8.9 kg CO2 (3). so 33.5 miles produces 0.8 g * 8.9 kg = 7.12 kg CO2 / 33.5 miles. Total CO2 cost of 100 miles = 2.26 kg + 3.87 kg+ 7.12 kg = 13.25 kg / 100 miles.

Please let me know what I did wrong with your calculations? It seems that the Hyundai Electric wins by a lot.
Sorry, I haven't had time to reply yet, but give me a bit more time. I appreciate all you input.
 
That might be????? It is EXACTLY what it is!!! The 150,000 km is already nonsense as many Bolts easily reached this number without large amounts of battery failure. Maybe if we were talking passively cooled Nissan Leafs I would agree with that 150,000 km number. I still don't agree with that 1 paper that says a battery takes between 150 kg to 300 kg (1 to 2 g / kWh / km for 150,000 km of battery lifespan) to make 1 kWh of battery. The average numbers are 70 kg to 110 kg (0.47 to 0.73 g / kWh / km for 150,000 km of battery lifespan) according to many sources. But you can't make your point using average data, you need to use that 1 paper for your argument. Below is data to show that the 150,000 km value is nonsense.


I am going to do your crazy calculation comparing your old Volt to a Hyundai Ioniq BEV using your calculation. You can't deny this :p

A lithium-ion car battery has a life cycle CO2 cost of about 1.5 g CO2 / kwh / km. (1)
The Hyundai Electric has a 28 kWh battery, so the CO2 cost is ~ 1.5g CO2 / kWh * 28 kWh / km * 1 km / 0.62 mi = 67.7 g CO2 / mi. = 0.0677 kg / mi.
The Volt has a 16 kWh battery, so the CO2 cost is ~ 1.5g CO2/kWh * 16 kWh / km * 1 km / 0.62 mi = 38.7 g CO2 / mi = 0.0387 kg / mi.

The Hyundai Electric has an MPGe of 136, or 25 kWh / 100 miles.
The Volt has an MPGe of 106, or 31 kWh / 100 miles.

For Oregon, the carbon intensity of electricity is ~ 0.11 kg / kWh. (2)

Hyundai Electric CO2 / 100 miles: 25 kWh / 100 mi * 0.11 kg / kWh + 0.0677 kg / mi * 100 mi = 9.52 kg / 100 miles.

Volt CO2 /100 miles
: I'm using your typical use of 66.5% EV mode. So, the Volt will travel 66.5 miles in EV mode and 33.5 miles in hybrid mode. EV mode CO2 cost is 31 kWh / 100 miles or 20.615 kWh / 66.5 miles * 0.11 kg CO2 / kWh = 2.26 kg CO2 / 66.5 miles for the electricity. The life-cycle battery cost is 100 mi *0.0387 kg / mi =3.87 kg. Then there will be 33.5 miles of hybrid mode at 42 miles / gal. So 33.5 miles / 42 mpg = ~0.8 gallons. 1 gal = 8.9 kg CO2 (3). so 33.5 miles produces 0.8 g * 8.9 kg = 7.12 kg CO2 / 33.5 miles. Total CO2 cost of 100 miles = 2.26 kg + 3.87 kg+ 7.12 kg = 13.25 kg / 100 miles.

Please let me know what I did wrong with your calculations? It seems that the Hyundai Electric wins by a lot.

Sorry it has taken a while to get back. After reading through the Swedish report I have done new calculations using a battery production CO2 cost of 72 kg / kWh. The Swedish study didn't include recycling costs as before of 15 kg / kWh which I think is important and must be added in, bringing the total CO2 production cost to 87 kg / kWh. I am also using the CO2 cost of electricity production of 0.5 kg / kWh as this is typical for the U.S. I also use an 8-year life for the battery since at least one study determined this was the expected lifetime before battery degradation functionally requires a replacement. You will probably disagree with this but lacking more informed information, I think this is appropriate, regardless of whether some EV owners have been using their cars longer. I also assume the typical yearly mileage of 15,000. I use 11 kg CO2 emissions / gallon of gas to account for full cycle costs. I have taken your report that Volt owners drive about 66.5% in EV mode and the rest in hybrid mode. I then put all this in a spreadsheet so I could run different scenarios easily. None of this accounts for the cost of producing and recycling the rest of the vehicle. Using these numbers, the Bolt does indeed come out ahead of the Volt, but not by much: 0.015 kg / mile. This does makes me feel a bit better about my choice to buy a Bolt, especially since the PNW has an electricity cost of just 0.11 kg / kWh. However, for people living in 12 states that have an electricity cost of 0.7 kg / kWh, the Volt comes out ahead. Also, for Volt owners who drive 83% of the time in EV mode, they will also do better. Somewhat depressing is the case for a 25 mpg gas car which gives a lifetime CO2 emissions from operation of just 12 tones CO2, just 7 tons more than a Bolt. Given that the per capita CO2 emission in the U.S. is about 15.5 tons / year, this is less than 6 months or normal living for one person. Driving an EV doesn't seem to be a very efficient way of reducing personal CO2 emissions, and the difference of 0.4 tons of lifetime emission of CO2 between a Bolt and a Volt is just a week and a half of one persons usual emissions. If you are counting on the grid getting cleaner, don't. The latest EPA data shows that electricity generation from low CO2 sources is currently 35% but this increases in 2050 to only 43%, a pitiful improvement. Within the lifetime of an EV, the grid won't change much at all. One last note: if the battery size increases to more than 110 kWh, the PHEV is the winner. Of course, those who put more than 120,000 miles on their battery will have a lower CO2 cost / mile.

27991
 
Problem converting kg to lbs in the last line. The numbers for total lifetime emissions should be

Bolt: 24.2 tons CO2
Volt: 26.2
Gas Car: 58 tons

The takeaway: EV and PHEV are pretty close and which is better depends on CO2 in electricity generation, size of the battery and how much a PHEV is driven n EV mode. But, the big gain is achieved with any electrification. For the given case, just switching to a PHEV reduces CO2 emissions by 55%. Changing to an EV reduces CO2 emissions by only another 3.4%, which is not much more considering the greater inconvenience of an EV. The 2 ton lifetime reduction amounts to less than 7 weeks of per capita US CO2 emissions.

Increasing the use to 20 years, 300,000 miles, makes the PHEV emit 23% more CO2 than the EV, an extra 12 tones CO2, less than 4% of per capita CO2 emissions.

Another way of looking at this is that in the given scenario, an EV does worse for the first 6 years and then gains an edge over the PHEV.

For low mileage drivers, say 6000 miles per year, an EV requires 9 years to break even with a PHEV. For PHEV drivers who drive more around town and drive 85% of the time in EV mode, almost 20 years will be needed for the EV to come out ahead.
 
Another way of looking at this is that in the given scenario, an EV does worse for the first 6 years and then gains an edge over the PHEV.
The size of the battery and how it is made is the biggest factor of CO2 emissions for a BEV. I am actually a huge fan of longer range PHEV's that can get 50 miles of range that can cover over 90% of an individuals driving. With the Volt being discontinued, what is the longest range PHEV? The Prius Prime/Hyundai Ioniq both get about 25 miles of all electric range. New cars like the Subaru Crosstrek PHEV get 17 miles of range. I am not liking this new type of PHEV. I think 50 miles of all electric range should be the number for a PHEV. These new PHEV's will be treated like hybrids and over 60% of driving will be on gas. The Volt with 53 miles was the best PHEV out there and it wasn't close!
 
Problem converting kg to lbs in the last line. The numbers for total lifetime emissions should be

Bolt: 24.2 tons CO2
Volt: 26.2
Gas Car: 58 tons

The takeaway: EV and PHEV are pretty close and which is better depends on CO2 in electricity generation, size of the battery and how much a PHEV is driven n EV mode. But, the big gain is achieved with any electrification. For the given case, just switching to a PHEV reduces CO2 emissions by 55%. Changing to an EV reduces CO2 emissions by only another 3.4%, which is not much more considering the greater inconvenience of an EV. The 2 ton lifetime reduction amounts to less than 7 weeks of per capita US CO2 emissions.

Increasing the use to 20 years, 300,000 miles, makes the PHEV emit 23% more CO2 than the EV, an extra 12 tones CO2, less than 4% of per capita CO2 emissions.

Another way of looking at this is that in the given scenario, an EV does worse for the first 6 years and then gains an edge over the PHEV.

For low mileage drivers, say 6000 miles per year, an EV requires 9 years to break even with a PHEV. For PHEV drivers who drive more around town and drive 85% of the time in EV mode, almost 20 years will be needed for the EV to come out ahead.
What happens if we also account for the CO2 related to maintenance of the gas engine in Gas Cars and PHEV?
 
The size of the battery and how it is made is the biggest factor of CO2 emissions for a BEV. I am actually a huge fan of longer range PHEV's that can get 50 miles of range that can cover over 90% of an individuals driving. With the Volt being discontinued, what is the longest range PHEV? The Prius Prime/Hyundai Ioniq both get about 25 miles of all electric range. New cars like the Subaru Crosstrek PHEV get 17 miles of range. I am not liking this new type of PHEV. I think 50 miles of all electric range should be the number for a PHEV. These new PHEV's will be treated like hybrids and over 60% of driving will be on gas. The Volt with 53 miles was the best PHEV out there and it wasn't close!
2021 RAV4 Prime will get about 50 EV miles.
 
The size of the battery and how it is made is the biggest factor of CO2 emissions for a BEV. I am actually a huge fan of longer range PHEV's that can get 50 miles of range that can cover over 90% of an individuals driving. With the Volt being discontinued, what is the longest range PHEV? The Prius Prime/Hyundai Ioniq both get about 25 miles of all electric range. New cars like the Subaru Crosstrek PHEV get 17 miles of range. I am not liking this new type of PHEV. I think 50 miles of all electric range should be the number for a PHEV. These new PHEV's will be treated like hybrids and over 60% of driving will be on gas. The Volt with 53 miles was the best PHEV out there and it wasn't close!
The Honda Clarity has an EV-mode range of 48 miles, but is only available in California.
The RAV4 Prime will have an EV-mode range of 39 miles according to the press release I read.

The average miles driven per day is about 37. So either of these would handle the average driver. But I don't know what the mean daily miles driven is, and the average could be skewed by few drivers.

I agree that the lower-range PHEVs would not travel nearly as much in EV mode as higher-range models. The relationship between EV-mode range and percent of miles driven in EV-mode would be interesting to know. My guess is that a PHEV with 60 miles of EV range could allow 90% of EV driving for most people. For the upcoming RAV4 Prime, those who are diligent about keeping charged and driving 66.5% of the time as an EV would emit about 20% more CO2 than a Bolt over 120,000 miles. Not too bad. Compared with upcoming BEV SUVs, a PHEV could be even more favorable. But a BEV SUV with a 100 kWh battery is no better than a RAV4 Prime. As I mentioned before, most of the improvement over an ICEV is achieved with any decent amount of electrification. Those concerned about compromises with a BEV could change to a PHEV without that concern while achieving most of the benefit.
 
What happens if we also account for the CO2 related to maintenance of the gas engine in Gas Cars and PHEV?
My guess is that fluids (oil, transmission fluid, etc.) are mostly recycled and almost never burned. So contribution to CO2 emissions would be from the supply chain. Given the small amount of lubricating fluids compared with the amount of FF burned as fuel, I doubt that it would make much of an impact, less than a rounding error.
 
My guess is that fluids (oil, transmission fluid, etc.) are mostly recycled and almost never burned. So contribution to CO2 emissions would be from the supply chain. Given the small amount of lubricating fluids compared with the amount of FF burned as fuel, I doubt that it would make much of an impact, less than a rounding error.
How do you recycle oil?!? I am pretty sure that's a no-no. Or are you saying that when I went to oil change, I am buying the old oil from the last car - filtered through a coffee filter?
 
I don't. I deliver it to the recycling collection point. It can then be sent to remove contaminants by various means and results in a product almost identical to virgin oil stock. This can be done indefinitely. It is not done on site except in large industrial applications where a lot of waste oil is produced. Used motor oil from oil changes is collected and sent to an appropriate recycler. I wouldn't recommend using a coffee filter.
 
I thought there was some thing about heat and the chemical degrading... you sure it's that easy to regenerate motor oil?!?
 
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