Electric VS petrol and diesel - without taxes...
Discussion
I've heard people say on the forums the only reason electric cars are cheaper to run than petrol diesel equivalents is the high taxes on fuel. I've been wondering about this for a while, so have taken a look at how much tax is on fuel and what difference it would make (as I'm a nerd and like spreadsheets).
Here's my working out if you are interested:
From http://www.petrolprices.com/the-price-of-fuel.html
In pence per litre:
So taxes proportions are:
Making petrol about 151% tax on the base cost, and diesel 142%. Ouch.
So with no taxes it would cost
A quick glance at some current cars MPGs tells me 50mpg is a typical figure for midsize petrol cars and 60mpg for Efficient diesels.
So to convert MPG to £/miles…
Now to compare that to a car charged on totally green electric...
I've chosen Good Energy to show that it is possible to run a non fossil fuel based car - cost competitively. They cost tiny bit more than the Big 6 - but not in all cases. Good Energy still need to make a profit, but they only buy their electrons to stick on the grid from renewable suppliers 99.4% of which involves not burning anything (Solar, wind, and water power). Only 0.6% is electrons made by burning biogas to power a generator.
http://www.goodenergy.co.uk/switch/where-our-energ...
Taking an i3 and assuming a worse case 0.35kWh/Mile (official is 0.3). I'm assuming you'll buy one that isn't just inside your daily commute range so you can use the heater and put your foot down and nip through amber lights once in a while.
From http://www.goodenergy.co.uk/switch/our-tariffs/goo...
These are the average figures across all of the supply regions from Good Energy... (noted how hard it is to get actual standing charge and unit rates from the big 6!?)
Inc VAT (@5%)
Exc VAT
The executive summary is that with current taxes cars running cost in pence per mile is:
So electric cars are cheaper to run without any fuel taxes but Economy 7 would be a must have to remain cost competitive.
Whilst we still have fuel duty (and presumably always will) it's still cheaper to charge a car using peak rate electric than buying petrol or diesel.
But you'd be foolish to do this regularly as it doubles the cost of your electric. It does mean that if you need to commute 80 miles each way and charge at work, it's not a deal breaker compared to buying a diesel.
Here's my working out if you are interested:
From http://www.petrolprices.com/the-price-of-fuel.html
In pence per litre:
Petrol | Diesel | Description |
---|---|---|
47.85 | 51.97 | Product |
57.95 | 57.95 | Duty |
22.15 | 22.98 | VAT |
5.00 | 5.00 | Retailer/delivery |
132.95 | 137.90 | Forecourt Price |
So taxes proportions are:
52.85 | 56.97 | Actual Costs |
80.10 | 80.93 | Tax Cost |
1.51 | 1.42 | Tax as a proportion of the costs |
Making petrol about 151% tax on the base cost, and diesel 142%. Ouch.
So with no taxes it would cost
47.85 | 51.97 | Product |
5.00 | 5.00 | Retailer/delivery |
52.85 | 56.97 | p/litre |
---|
A quick glance at some current cars MPGs tells me 50mpg is a typical figure for midsize petrol cars and 60mpg for Efficient diesels.
So to convert MPG to £/miles…
Diesel | Petrol | Description |
---|---|---|
50 | 60 | miles per gallon |
4.546 | 4.546 | litres per gallon |
10.998 | 13.198 | miles per litre |
0.090 | 0.075 | litres per mile |
12.088 | 10.448 | p/mile taxed |
4.805 | 4.316 | p/mile no tax |
Now to compare that to a car charged on totally green electric...
I've chosen Good Energy to show that it is possible to run a non fossil fuel based car - cost competitively. They cost tiny bit more than the Big 6 - but not in all cases. Good Energy still need to make a profit, but they only buy their electrons to stick on the grid from renewable suppliers 99.4% of which involves not burning anything (Solar, wind, and water power). Only 0.6% is electrons made by burning biogas to power a generator.
http://www.goodenergy.co.uk/switch/where-our-energ...
Taking an i3 and assuming a worse case 0.35kWh/Mile (official is 0.3). I'm assuming you'll buy one that isn't just inside your daily commute range so you can use the heater and put your foot down and nip through amber lights once in a while.
From http://www.goodenergy.co.uk/switch/our-tariffs/goo...
These are the average figures across all of the supply regions from Good Energy... (noted how hard it is to get actual standing charge and unit rates from the big 6!?)
Inc VAT (@5%)
p/kWh | p/mile | |
---|---|---|
15.97 | 5.59 | Peak Rate |
8.30 | 2.91 | Economy7 |
Exc VAT
p/kWh | p/mile | |
---|---|---|
15.22 | 5.33 | Peak Rate |
7.91 | 2.77 | Economy 7 |
The executive summary is that with current taxes cars running cost in pence per mile is:
Petrol | Diesel | Economy 7 | Peak Rate | |
---|---|---|---|---|
12.1 | 10.4 | 2.9 | 5.5 | With Fuel Taxes |
4.8 | 4.3 | 2.8 | 5.3 | Without Taxes |
So electric cars are cheaper to run without any fuel taxes but Economy 7 would be a must have to remain cost competitive.
Whilst we still have fuel duty (and presumably always will) it's still cheaper to charge a car using peak rate electric than buying petrol or diesel.
But you'd be foolish to do this regularly as it doubles the cost of your electric. It does mean that if you need to commute 80 miles each way and charge at work, it's not a deal breaker compared to buying a diesel.
TransverseTight said:
Diesel | Petrol | Description |
---|---|---|
50 | 60 | miles per gallon |
4.546 | 4.546 | litres per gallon |
10.998 | 13.198 | miles per litre |
0.090 | 0.075 | litres per mile |
12.088 | 10.448 | p/mile taxed |
4.805 | 4.316 | p/mile no tax |
16p/kwh seems pricey... Think I'm on about 12incl vat.... My ev is on 0.3/mile.... My last 3l diesel was meant to do 40plus mpg, but we struggled to get 27 average.
You're not taking into account the fact that most ev use is relatively short distance local trips..... My use is several 3-5m trips during the course of a typical day.
Your normal ice car (especially modern turbo diesels) are poor on fuel over these distances.... I rarely got better than 30mpg in a ice car over these distances. Ice engines only really get the 50-60 mpg if driven over much longer distances, or on motorways etc.
So... Please refresh using 12p/kwh and 30mpg.... That would be more representative of my situation, and probably the same for a lot of other ev users.....
You're not taking into account the fact that most ev use is relatively short distance local trips..... My use is several 3-5m trips during the course of a typical day.
Your normal ice car (especially modern turbo diesels) are poor on fuel over these distances.... I rarely got better than 30mpg in a ice car over these distances. Ice engines only really get the 50-60 mpg if driven over much longer distances, or on motorways etc.
So... Please refresh using 12p/kwh and 30mpg.... That would be more representative of my situation, and probably the same for a lot of other ev users.....
Interesting to see the electricity rate variations. I'm on 16.6p / kwh during day, and 6.4p overnight.
My EV seems to have a lifetime average usage so far of 271 wh/mile. This might seem low'ish but its got a relatively small frontal area so the Cda is low, and 90%+ of the time its moving at a steady speed - you cant accelerate all the time !! However the opening post reckons on 350 wh/mile average which is high and in Tesla Model S 2-ton EV territory.
99% of the time mine is topped up at night, and even though its 'free' on the move I rarely ever bother unless I really am doing a 300-400 mile journey, which is about once per year.
I'm getting 1/0.271 = 3.69 miles per Kwh. At 6.4p per Kwh, that means its costing 1.73 pence per mile. In other words 10,000 miles annually is costing just £173 ... which works out at about 1.5 tanks of petrol in my petrol car. Daft or what ?
We also have an aging Audi A6 Tdi with a lifetime average of 44mpg and 190,000 miles on the clock. Diesel round here is currently £6.31 per gallon. So that works out at 14.3 pence per mile. According to Govt stats, the average MPG in the UK for family cars is currently 34mpg, or approximately 18 pence per mile.
There's also the small matter of another car here with a ludicrously low average of around 14mpg, so that's working out at a whopping 45p per mile, and all its sub 100mph performance figures are thoroughly hammered by the EV.
In conclusion:- our very efficient diesel car is still 8 times more costly per mile than the EV, and the petrol monster costs 26 times more per mile to run.
____________________________________
Bonus statement :-
A UK gallon of petrol has 44kwh energy stored chemically and costs about £6.30, whereas an EV can drive approx 162 miles on the same amount of energy for about £2.80 worth of night time electricity.
Or put another way, for the cost of a gallon of fuel, the EV can drive approx 365 miles.
____________________________________
Another view point is "what if your house has Solar PV on the roof ?". If you have paid a rip off solar installer to put 4kw on your roof for around £7k to £9k, the feed in tariff you will currently get is 15p / Kwh typically yielding about £500-600 per year. In other words, you indirectly get PAID about 4p a mile to drive an EV. Also, to drive 10,000 miles a year fuelled by solar in the UK will require a modest PV installation of around 3.5kw, so a typical 4kw set-up will entirely offset the energy needs for charging your EV.
If you really really wanted to make a point about your eco credentials, or are off-grid, you could put your own 4kw system up for around £2k (trade price for new panels in the UK inc vat..), buffer the energy with a modest lead acid battery bank and charge you car direct from sunlight (when its sunny ...). But if you are grid connected its still way way cheaper to just top it up at night.
My EV seems to have a lifetime average usage so far of 271 wh/mile. This might seem low'ish but its got a relatively small frontal area so the Cda is low, and 90%+ of the time its moving at a steady speed - you cant accelerate all the time !! However the opening post reckons on 350 wh/mile average which is high and in Tesla Model S 2-ton EV territory.
99% of the time mine is topped up at night, and even though its 'free' on the move I rarely ever bother unless I really am doing a 300-400 mile journey, which is about once per year.
I'm getting 1/0.271 = 3.69 miles per Kwh. At 6.4p per Kwh, that means its costing 1.73 pence per mile. In other words 10,000 miles annually is costing just £173 ... which works out at about 1.5 tanks of petrol in my petrol car. Daft or what ?
We also have an aging Audi A6 Tdi with a lifetime average of 44mpg and 190,000 miles on the clock. Diesel round here is currently £6.31 per gallon. So that works out at 14.3 pence per mile. According to Govt stats, the average MPG in the UK for family cars is currently 34mpg, or approximately 18 pence per mile.
There's also the small matter of another car here with a ludicrously low average of around 14mpg, so that's working out at a whopping 45p per mile, and all its sub 100mph performance figures are thoroughly hammered by the EV.
In conclusion:- our very efficient diesel car is still 8 times more costly per mile than the EV, and the petrol monster costs 26 times more per mile to run.
____________________________________
Bonus statement :-
A UK gallon of petrol has 44kwh energy stored chemically and costs about £6.30, whereas an EV can drive approx 162 miles on the same amount of energy for about £2.80 worth of night time electricity.
Or put another way, for the cost of a gallon of fuel, the EV can drive approx 365 miles.
____________________________________
Another view point is "what if your house has Solar PV on the roof ?". If you have paid a rip off solar installer to put 4kw on your roof for around £7k to £9k, the feed in tariff you will currently get is 15p / Kwh typically yielding about £500-600 per year. In other words, you indirectly get PAID about 4p a mile to drive an EV. Also, to drive 10,000 miles a year fuelled by solar in the UK will require a modest PV installation of around 3.5kw, so a typical 4kw set-up will entirely offset the energy needs for charging your EV.
If you really really wanted to make a point about your eco credentials, or are off-grid, you could put your own 4kw system up for around £2k (trade price for new panels in the UK inc vat..), buffer the energy with a modest lead acid battery bank and charge you car direct from sunlight (when its sunny ...). But if you are grid connected its still way way cheaper to just top it up at night.
Edited by Carparticus on Tuesday 5th August 11:45
isleofthorns said:
16p/kwh seems pricey... Think I'm on about 12incl vat.... My ev is on 0.3/mile.... My last 3l diesel was meant to do 40plus mpg, but we struggled to get 27 average.
You're not taking into account the fact that most ev use is relatively short distance local trips..... My use is several 3-5m trips during the course of a typical day.
Your normal ice car (especially modern turbo diesels) are poor on fuel over these distances.... I rarely got better than 30mpg in a ice car over these distances. Ice engines only really get the 50-60 mpg if driven over much longer distances, or on motorways etc.
So... Please refresh using 12p/kwh and 30mpg.... That would be more representative of my situation, and probably the same for a lot of other ev users.....
I specifically chose Good Energy as I know they are not the cheapest - they are "worst case" assuning you want a carbon free motor. If not and saving money rather than CO2 is your goal you'll be even better off. You're not taking into account the fact that most ev use is relatively short distance local trips..... My use is several 3-5m trips during the course of a typical day.
Your normal ice car (especially modern turbo diesels) are poor on fuel over these distances.... I rarely got better than 30mpg in a ice car over these distances. Ice engines only really get the 50-60 mpg if driven over much longer distances, or on motorways etc.
So... Please refresh using 12p/kwh and 30mpg.... That would be more representative of my situation, and probably the same for a lot of other ev users.....
Noted - I messed up the 2nd table. I spotted the table feature on the forum after I pasted the raw text in from Excel. It looked naff so tidied it up with the tables.
I can't see the relevance of the having a set of results generated by using a "worst case" electricity contract, a 'best case' ICE fuel consumption figure and the crux of the whole matter, NO fuel duty!.
I imagine some people will sign up to an ECO contract to run their EV's, but I would think this is in the minority. I would imagine more would go down the solar panel route, if they are after zero-carbon transport.
The better 'tax' point to make (from my own perspective at least) is one from the real-world.
My my EV costs approx. 3.6p/mile - if you gross this up as salary (at 40% for simplicity), this is approx. 6p/mile out of gross earnings. From my short-journey ICE fuel consumption figures (approx 30mpg), this equates to approx. 21p/mpg net of income tax, or 35p/mile in gross salary.
In short, I need to pay income tax of 14p/mile just to put pay myself the money to put petrol in the tank - or nearly 6 times the equivalent income tax needed to run the EV!! In absolute terms, just the 14p/mile income tax is more than twice the total EV/mile cost!
As I also run the car as a company car, the additional benefits of having the company suffer the depreciation and running costs is very compelling. Roughly speaking, I expect the monthly cost to the company to pan out at between 250-340/per month over three years of ownership. Taking the bottom figure and assuming I was running the cost personally, this would equate to approx gbp166 per month in additional income tax. Given that I travel about 1000m a month, this would be an additional 16.6p/mile in income tax!!
Obviously, not everyone can run their EV's though a company, so the benefits are not universal. Also, you would have to take into account the current high levels of depreciation for personal buyers, as the tax benefits would soon be wiped out by the loss. An old X5 is probably cheaper to run! However, with low-mileage, non-battery lease Leafs up for early teens, the financial argument is surely swinging back in favour of EV's. I think the prices of the non-battery lease cars must surely start to firm up as more people do the sums.
All this assumes, of course, that your requirements suit an EV in the first place. The R-Ex i3 looks very interesting., but this time I'll wait for the initial depreciation to hit before I switch!
I imagine some people will sign up to an ECO contract to run their EV's, but I would think this is in the minority. I would imagine more would go down the solar panel route, if they are after zero-carbon transport.
The better 'tax' point to make (from my own perspective at least) is one from the real-world.
My my EV costs approx. 3.6p/mile - if you gross this up as salary (at 40% for simplicity), this is approx. 6p/mile out of gross earnings. From my short-journey ICE fuel consumption figures (approx 30mpg), this equates to approx. 21p/mpg net of income tax, or 35p/mile in gross salary.
In short, I need to pay income tax of 14p/mile just to put pay myself the money to put petrol in the tank - or nearly 6 times the equivalent income tax needed to run the EV!! In absolute terms, just the 14p/mile income tax is more than twice the total EV/mile cost!
As I also run the car as a company car, the additional benefits of having the company suffer the depreciation and running costs is very compelling. Roughly speaking, I expect the monthly cost to the company to pan out at between 250-340/per month over three years of ownership. Taking the bottom figure and assuming I was running the cost personally, this would equate to approx gbp166 per month in additional income tax. Given that I travel about 1000m a month, this would be an additional 16.6p/mile in income tax!!
Obviously, not everyone can run their EV's though a company, so the benefits are not universal. Also, you would have to take into account the current high levels of depreciation for personal buyers, as the tax benefits would soon be wiped out by the loss. An old X5 is probably cheaper to run! However, with low-mileage, non-battery lease Leafs up for early teens, the financial argument is surely swinging back in favour of EV's. I think the prices of the non-battery lease cars must surely start to firm up as more people do the sums.
All this assumes, of course, that your requirements suit an EV in the first place. The R-Ex i3 looks very interesting., but this time I'll wait for the initial depreciation to hit before I switch!
If more people started using your green tariff, two things would happen
1. There wouldn't be enough energy to go round
2. The company would get bigger bigger and cross the threshold whereby it starts having to pay the green levy to fund the subsidies it recieves. This would increase the cost of the electricity to you.
As an aside, why not compress the biogas and put in my LPG-powered Impreza?
1. There wouldn't be enough energy to go round
2. The company would get bigger bigger and cross the threshold whereby it starts having to pay the green levy to fund the subsidies it recieves. This would increase the cost of the electricity to you.
As an aside, why not compress the biogas and put in my LPG-powered Impreza?
Carparticus said:
We also have an aging Audi A6 Tdi with a lifetime average of 44mpg and 190,000 miles on the clock. Diesel round here is currently £6.31 per gallon. So that works out at 6.97 pence per mile. According to Govt stats, the average MPG in the UK for family cars is currently 34mpg, or approximately 18pence per gallon overall.
I think your pence per mile is somewhat incorrect there anyway when you said it was 4 times more costly..... 10mpg less average triples the pence per mile.....bit glaring ?Edited by JonnyVTEC on Tuesday 5th August 10:02
JonnyVTEC said:
I think your pence per mile is somewhat incorrect there anyway when you said it was 4 times more costly..... 10mpg less average triples the pence per mile.....bit glaring ?
[/footnote]
hah ! Good spot. [/footnote]
I somehow did an incorrect division on the diesel calculation, and corrected it above. The particular quote should now read :-
Carparticus said:
We also have an aging Audi A6 Tdi with a lifetime average of 44mpg and 190,000 miles on the clock. Diesel round here is currently £6.31 per gallon. So that works out at 14.3 pence per mile. According to Govt stats, the average MPG in the UK for family cars is currently 34mpg, or approximately 18 pence per mile.
Mr Taxpayer said:
If more people started using your green tariff, two things would happen
1. There wouldn't be enough energy to go round
2. The company would get bigger bigger and cross the threshold whereby it starts having to pay the green levy to fund the subsidies it recieves. This would increase the cost of the electricity to you.
As an aside, why not compress the biogas and put in my LPG-powered Impreza?
I used Green electric in the original calcs as it costs more than standard already l. I was looking at the worst case cost in the current market place. You can get nuclear mostly nuclear electric from edf if you ate near the interconnection or any other combination both cheaper than green electric tariffs. 1. There wouldn't be enough energy to go round
2. The company would get bigger bigger and cross the threshold whereby it starts having to pay the green levy to fund the subsidies it recieves. This would increase the cost of the electricity to you.
As an aside, why not compress the biogas and put in my LPG-powered Impreza?
So my point still stands. Even without fuel duty an green subsidies it is still cheaper to run an EV.
If you start adding what if scenarios and it gets too complicated. I could day what if they cut all green subsidies bur started putting a carbon tax on non green electric. Or what if russia fell out woth the EU cut the gas supply causing a price in the spike of electric generation so that renewables actually were cheaper without subsidy. All possible but not in the current market price.
Carparticus said:
JonnyVTEC said:
I think your pence per mile is somewhat incorrect there anyway when you said it was 4 times more costly..... 10mpg less average triples the pence per mile.....bit glaring ?
[/footnote]
hah ! Good spot. [/footnote]
My only interest in an EV (and it looks like I will be ordering the Mitsubishi Outlander PHEV this week)is the BiK rate for a company car which at 40% is £66 per month. If you are looking at a company car purchase then an EV is a good move I think.
For me, it will be my daily commute (20 miles) and I'll plug it in at work.
I will burn fuel in my other cars at the weekend and days when i get bored
For me, it will be my daily commute (20 miles) and I'll plug it in at work.
I will burn fuel in my other cars at the weekend and days when i get bored
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