Energy prices.

[S-Rail]

Anything to do with government and computers is fraught with danger, there is already talk of speed limits by satalite direct to vehicles so billing for miles could be next step, see what Norway are going to do they have high EV take up

And funnily enough they just brought in a bunch of new laws regarding vehicle mods , of which included an Anti-Tampering” section , can see how that is needed when some clever wiz will work out how to reprogram cars to show less miles …

20 years when some people said about the whole Big Brother thing , others laughed …..

 

[willie.macleod]

I worked it out recently that a Tesla model S which is the most efficient electric car available works out about the same as running a normal diesel car at around 45mpg - taking all fuel taxes out of the equation.
Electric cars seem cheap because you aren't paying tax - yet!

The Tesla model S certainly isn't the most efficient electric car available - 3.9 miles per kWh, I got better figures in my old Leaf today! Much depends on how you drive the car. Hyundai seem to be able to turn out cars that can realistically do closer to 5 miles per kWh.

A kWh of electricity is around 30p, so fuel costs for model S comes in around 8p a mile.

Diesel here is £1.80 a litre or thereabouts, so £1.80*4.55=£8.19 a gallon. Divide that by 0.08 and you need a diesel car that can do over a hundred miles to the gallon to come close to equalising the fuel cost of the electric option.

Now, if you filled up on rapid chargers at 60p/kWh I can understand how the numbers are a lot closer but why make things worse than they are? Folk only use the expensive charging options where they have to and take the minimum they need to get home/to a cheaper option. I can fill up at the nearest rapid for 25p/kWh and if you are a heavy user you will go onto a economy 7 tariff or similar and charge off peak at lower costs still.

If taxes go up on electric cars (which they inevitably will) then it is likely to be some form of pay per mile charges which might as well be implemented for all road users such as in congestion schemes. Too easy for the general public to capture their own using solar/wind or transfer it through unmetered means. The cost of electricity cannot go up much more as we are so dependant on electricity for so much in the way of cooking/heating/lighting and the move away from gas to electric will only be slowed down if electricity skyrockets again.

My 100mpg 125cc motorbike is not as efficient as my Leaf - it uses more energy (44kWh) to travel 100 miles although it turns a large amount of that stored energy into heat and noise. If my Leaf can travel the same distance using 30kWh carrying 4 passengers and cargo with fewer emissions then why should it be taxed more? I already pay a fortune to HMRC per month including road taxes for multiple petrol and diesel vehicles. I'd be upset if my newest and cleanest vehicle cost the most to run - electric cars need to drop in price and running costs have to be affordable or we will end up with a situation in a few years where those in the lower income brackets are simply priced out of their cars. That would be a disaster in so many ways and decimate rural communities further.

 

[daleyd]

The Tesla model S certainly isn't the most efficient electric car available - 3.9 miles per kWh, I got better figures in my old Leaf today! Much depends on how you drive the car. Hyundai seem to be able to turn out cars that can realistically do closer to 5 miles per kWh.

A kWh of electricity is around 30p, so fuel costs for model S comes in around 8p a mile.

Diesel here is £1.80 a litre or thereabouts, so £1.80*4.55=£8.19 a gallon. Divide that by 0.08 and you need a diesel car that can do over a hundred miles to the gallon to come close to equalising the fuel cost of the electric option.

Now, if you filled up on rapid chargers at 60p/kWh I can understand how the numbers are a lot closer but why make things worse than they are? Folk only use the expensive charging options where they have to and take the minimum they need to get home/to a cheaper option. I can fill up at the nearest rapid for 25p/kWh and if you are a heavy user you will go onto a economy 7 tariff or similar and charge off peak at lower costs still.

If taxes go up on electric cars (which they inevitably will) then it is likely to be some form of pay per mile charges which might as well be implemented for all road users such as in congestion schemes. Too easy for the general public to capture their own using solar/wind or transfer it through unmetered means. The cost of electricity cannot go up much more as we are so dependant on electricity for so much in the way of cooking/heating/lighting and the move away from gas to electric will only be slowed down if electricity skyrockets again.

My 100mpg 125cc motorbike is not as efficient as my Leaf - it uses more energy (44kWh) to travel 100 miles although it turns a large amount of that stored energy into heat and noise. If my Leaf can travel the same distance using 30kWh carrying 4 passengers and cargo with fewer emissions then why should it be taxed more? I already pay a fortune to HMRC per month including road taxes for multiple petrol and diesel vehicles. I'd be upset if my newest and cleanest vehicle cost the most to run - electric cars need to drop in price and running costs have to be affordable or we will end up with a situation in a few years where those in the lower income brackets are simply priced out of their cars. That would be a disaster in so many ways and decimate rural communities further.

I think what he did was took all the taxes off the fuel (though not the circa 18% green levy and VAT you pay on electric , which should have been done to make it fair) and worked out it would be equivalent to 40 odd mpg, but purely on price - though on pure energy input as you say most calculations seem to suggest EVs are in the hundred odd mpg equivalent range.

 

[willie.macleod]

That's not entirely accurate.

If you factor in electricity generation and charging losses (except when charging with an idealised charger), the power used to move an EV and a hybrid diesel vehicle a unit distance is much the same.

There are theoretical circumstances in which a hybrid diesel is more efficient than an EV, for instance when utilising regenerative braking in city driving or exhaust gas recovery during sustained high speed driving.

If we take my situation, the energy used by my electric car is coming from three 0.9MW wind turbines a mile away. Where's the diesel and petrol coming from that I fill up other vehicles with? Where was it drilled? Where was it refined? The journey alone to get it to my tank from the hole in the ground is mind boggling. Remember I can reclaim 10% of my energy through regeneration. In town drivers will have a far higher % regen.

Those turbines alone are producing more than enough energy for the local area. We have far more generation capacity here than we can use and they keep spinning as we are a suitable windy location. Charging and grid transmission losses are there, but nothing compared to what you are talking about drilling/refining/shipping oil. The whole idea that a diesel vehicle comes close to an EV in efficiency in a whole picture scenario is one that I find hard to believe. Think of all that energy lost due to heat in your diesel engine - more than 50%? Burn it in an CHP station and use that heat wisely and efficiently. Use the electricity to power the car.

We need better control of the grid for managing increased levels of EVs, once we properly integrate V2G and remote switching of chargers we can improve grid efficiency and load balancing. Enable users to set their own charging preferences based on time of charge/grid capacity/desired range etc.

 

[premmington]

The Tesla model S certainly isn't the most efficient electric car available - 3.9 miles per kWh, I got better figures in my old Leaf today! Much depends on how you drive the car. Hyundai seem to be able to turn out cars that can realistically do closer to 5 miles per kWh.

A kWh of electricity is around 30p, so fuel costs for model S comes in around 8p a mile.

Diesel here is £1.80 a litre or thereabouts, so £1.80*4.55=£8.19 a gallon. Divide that by 0.08 and you need a diesel car that can do over a hundred miles to the gallon to come close to equalising the fuel cost of the electric option.

Now, if you filled up on rapid chargers at 60p/kWh I can understand how the numbers are a lot closer but why make things worse than they are? Folk only use the expensive charging options where they have to and take the minimum they need to get home/to a cheaper option. I can fill up at the nearest rapid for 25p/kWh and if you are a heavy user you will go onto a economy 7 tariff or similar and charge off peak at lower costs still.

If taxes go up on electric cars (which they inevitably will) then it is likely to be some form of pay per mile charges which might as well be implemented for all road users such as in congestion schemes. Too easy for the general public to capture their own using solar/wind or transfer it through unmetered means. The cost of electricity cannot go up much more as we are so dependant on electricity for so much in the way of cooking/heating/lighting and the move away from gas to electric will only be slowed down if electricity skyrockets again.

My 100mpg 125cc motorbike is not as efficient as my Leaf - it uses more energy (44kWh) to travel 100 miles although it turns a large amount of that stored energy into heat and noise. If my Leaf can travel the same distance using 30kWh carrying 4 passengers and cargo with fewer emissions then why should it be taxed more? I already pay a fortune to HMRC per month including road taxes for multiple petrol and diesel vehicles. I'd be upset if my newest and cleanest vehicle cost the most to run - electric cars need to drop in price and running costs have to be affordable or we will end up with a situation in a few years where those in the lower income brackets are simply priced out of their cars. That would be a disaster in so many ways and decimate rural communities further.

Your quote "My 100mpg 125cc motorbike is not as efficient as my Leaf".

I got a 108cc Honda AFS110 wave. Really shocked me the above.

I don't disbelieve you - but I would have never have thought that.

 

[Mr Fro]

If we take my situation, the energy used by my electric car is coming from three 0.9MW wind turbines a mile away. Where's the diesel and petrol coming from that I fill up other vehicles with? Where was it drilled? Where was it refined? The journey alone to get it to my tank from the hole in the ground is mind boggling. Remember I can reclaim 10% of my energy through regeneration. In town drivers will have a far higher % regen.

Those turbines alone are producing more than enough energy for the local area. We have far more generation capacity here than we can use and they keep spinning as we are a suitable windy location. Charging and grid transmission losses are there, but nothing compared to what you are talking about drilling/refining/shipping oil. The whole idea that a diesel vehicle comes close to an EV in efficiency in a whole picture scenario is one that I find hard to believe. Think of all that energy lost due to heat in your diesel engine - more than 50%? Burn it in an CHP station and use that heat wisely and efficiently. Use the electricity to power the car.

We need better control of the grid for managing increased levels of EVs, once we properly integrate V2G and remote switching of chargers we can improve grid efficiency and load balancing. Enable users to set their own charging preferences based on time of charge/grid capacity/desired range etc.

As you state, if we all have our own renewable source of electricity then EV is a clear winner.

Unfortunately we do not and the majority of the electricity in the UK is derived from fossil fuel. There's an illustrative graph somewhere in this thread.

From memory, UK generation is on average around 50% efficient at converting the energy from the prime source (fossil, biomass, hydro, nuclear etc) to electrical energy once losses are accounted for. These data are readily available at the gov.uk website.

EV charging efficiency is on average 78% (from memory). This figure is below the efficiency figures published by car manufacturers because the majority of people don't have access to the idealised charger used during the manufacturer's test procedure (surprise). Again, there are plenty of peer reviewed documents available.

A high efficiency diesel engined car can convert 40 - 45% of the energy in the fuel to motive power so as you will appreciate, it's not a huge jump to the ~50% efficiency of UK electricity generation.

The theoretical case I alluded to earlier was from an offshoot of a piece of research I conducted to show the benefits of EV over ICE. My expectation was to demonstrate the inefficiencies of ICE when compared to EV but the data analysis proved otherwise. This led me to model the effect of exhaust energy recovery and/or regenerative braking using the WLTP as a modelling tool. The result was that a high efficiency diesel engined car could be slightly more efficient in certain scenarios than the average EV when equipped with waste energy capture technology.

The argument around having to dig up/extract/refine petrol and diesel is somewhat nullified by the UK electricity generation being heavily dependent on fossil fuel. The extra penalty of refinement and transportation to the filling station is pretty much lost in the noise.

 

[premmington]

As you state, if we all have our own renewable source of electricity then EV is a clear winner.

Unfortunately we do not and the majority of the electricity in the UK is derived from fossil fuel. There's an illustrative graph somewhere in this thread.

From memory, UK generation is on average around 50% efficient at converting the energy from the prime source (fossil, biomass, hydro, nuclear etc) to electrical energy once losses are accounted for. These data are readily available at the gov.uk website.

EV charging efficiency is on average 78% (from memory). This figure is below the efficiency figures published by car manufacturers because the majority of people don't have access to the idealised charger used during the manufacturer's test procedure (surprise). Again, there are plenty of peer reviewed documents available.

A high efficiency diesel engined car can convert 40 - 45% of the energy in the fuel to motive power so as you will appreciate, it's not a huge jump to the ~50% efficiency of UK electricity generation.

The theoretical case I alluded to earlier was from an offshoot of a piece of research I conducted to show the benefits of EV over ICE. My expectation was to demonstrate the inefficiencies of ICE when compared to EV but the data analysis proved otherwise. This led me to model the effect of exhaust energy recovery and/or regenerative braking using the WLTP as a modelling tool. The result was that a high efficiency diesel engined car could be slightly more efficient in certain scenarios than the average EV when equipped with waste energy capture technology.

The argument around having to dig up/extract/refine petrol and diesel is somewhat nullified by the UK electricity generation being heavily dependent on fossil fuel. The extra penalty of refinement and transportation to the filling station is pretty much lost in the noise.

This debate is going to go for long while..

But @Mr Fro makes a good arguement above

​

 

[willie.macleod]

Your quote "My 100mpg 125cc motorbike is not as efficient as my Leaf".

I got a 108cc Honda AFS110 wave. Really shocked me the above.

I don't disbelieve you - but I would have never have thought that.

I'll say this for Honda, their newest CB125F is another step up - it is supposedly a true 150mpg, so I wouldn't beat that with the Leaf (if I am travelling 1 up and have no cargo!)

Your AFS is probably on par with the Leaf, I'd have thought it would do a bit more than 100mpg?

 

[premmington]

I'll say this for Honda, their newest CB125F is another step up - it is supposedly a true 150mpg, so I wouldn't beat that with the Leaf (if I am travelling 1 up and have no cargo!)

Your AFS is probably on par with the Leaf, I'd have thought it would do a bit more than 100mpg?

The AFS - will do (and I have checked). About 120mpg - dragging me about - the full 100kg fat boy.

Most of the journeys I do - are short and thru housing estates and town roads. Thru the gears mostly.

I would think on a level run with a "skinny" person on it - with no hills and no wind with tyres pumped up/chain adjusted and oiled - it may even hit near 150mpg.

AFS is Euro3 with a CAT. When you take the plug out - you can see how well it meters the fuel into it. True evolution of the C90.

 

[willie.macleod]

EV charging efficiency is on average 78% (from memory). This figure is below the efficiency figures published by car manufacturers because the majority of people don't have access to the idealised charger used during the manufacturer's test procedure (surprise). Again, there are plenty of peer reviewed documents available.

I appreciate what you are saying and I'm sure we will agree on many matters, however I can't let the 78% charging efficiency figure go. That can be disproved very quickly and easily by those of us who meter our EVs energy usage both at that wall and in the car. To get a figure that low you are looking at either a level 1 EVSE using 120v charging at ~10A, something nobody in this country does or you are using the figures for a Renault Zoe which has a particularly interesting charger design which helpfully allows it to pull 22kWh from widely available 3 phase charging posts as it incorporates the motor windings in its design at the cost of poor single phase charging efficiency. Your average home charger is a 240V 7kWh unit and that should get an efficiency of around 90% in most EVs.

 

[daleyd]

Taking renewables and nuclear into account then over half our electricity is not actually generated from fossil fuels.

 

[Mr Fro]

I appreciate what you are saying and I'm sure we will agree on many matters, however I can't let the 78% charging efficiency figure go. That can be disproved very quickly and easily by those of us who meter our EVs energy usage both at that wall and in the car. To get a figure that low you are looking at either a level 1 EVSE using 120v charging at ~10A, something nobody in this country does or you are using the figures for a Renault Zoe which has a particularly interesting charger design which helpfully allows it to pull 22kWh from widely available 3 phase charging posts as it incorporates the motor windings in its design at the cost of poor single phase charging efficiency. Your average home charger is a 240V 7kWh unit and that should get an efficiency of around 90% in most EVs.

I'm sure you are right in what you're saying about your own circumstances however, you are a very small data set.

When you consider large the national situation then the situation is different. Bear in mind I've not looked at the research for a year so it'll be a year bit I recall charging efficiencies from ~ 50 - ~90% with the average being ~78%. Also, how are you measuring your efficiency? Is it what the charger tells you or are you measuring consumption before the charger and in the car?

Anyway, I'll dig out my paper today to give a better response to you and @daleyd .

 

[RaceDiagnostics]

Surely chargers must be highly efficient, greater than 90%, or they would melt from the heat generated.

They are all in effect switch mode power supplies which are very efficient.

The inefficiency is manifested in how that energy is stored and deployed once it's in the car.

 

[atomant48]

I'm sure you are right in what you're saying about your own circumstances however, you are a very small data set.

When you consider large the national situation then the situation is different. Bear in mind I've not looked at the research for a year so it'll be a year bit I recall charging efficiencies from ~ 50 - ~90% with the average being ~78%. Also, how are you measuring your efficiency? Is it what the charger tells you or are you measuring consumption before the charger and in the car?

Anyway, I'll dig out my paper today to give a better response to you and @daleyd .

It’s an interesting area this efficiency. I’ve never thought about it but I’d be pretty upset if 20% of the diesel I paid for went out onto the forecourt. That said I suspect the measurement of the efficiency is subjective - for example my EV does a lot of things in the background particularly while it’s charging so it might not be so much a case of watts in vs watts in the battery?

 

[Munkul]

I’ve never thought about it but I’d be pretty upset if 20% of the diesel I paid for went out onto the forecourt.

What about the 50-60% of the of the diesel that you paid for which goes straight into the sky while you're trying to get it to push you along?

I've always been operating on older and more cynical figures for ICE vs electric, but the last few pages have opened my eyes a bit to be honest. I had NOT realised how supendously efficient per KW an electric car can be when you work it out in KWh per mile (or miles per KWh which I didn't think was possible!)

Still limited on storage capacity though. That's my sticking point.

 

[Gareth J]

I'm sure you are right in what you're saying about your own circumstances however, you are a very small data set.

When you consider large the national situation then the situation is different. Bear in mind I've not looked at the research for a year so it'll be a year bit I recall charging efficiencies from ~ 50 - ~90% with the average being ~78%. Also, how are you measuring your efficiency? Is it what the charger tells you or are you measuring consumption before the charger and in the car?

Anyway, I'll dig out my paper today to give a better response to you and @daleyd .

I asked previously but can't recall if you mentioned it or not, did you also factor in losses for diesel/fuel from well to tank as well as the inefficiencies associated with filling a battery vehicle?

https://www.google.com/url?q=https://publications.jrc.ec.europa.eu/repository/bitstream/JRC85326/wtt_report_v4a_april2014_pubsy.pdf&sa=U&ved=2ahUKEwj6rv7exNT3AhVOTsAKHXA0A68QFnoECAkQAg&usg=AOvVaw2W29B1xXVOXbsY_praGO9C

For diesel, it's about an extra 0.2MJ/MJ(final).

 

[Mr Fro]

Extracts from paper:

Assuming the average actual real-world fuel economy of petrol ICEV as 35.94 miles/gallon and diesel ICEV as 42.93 miles/gallon (Sprintmonitor.de, 2021). From this the power used per unit distance can be calculated:

As of the January 2021, there were 56 commercially available fully electric vehicles . The average manufacturer published energy consumption of these is 173 Wh/km and 36.9 gCO2/km:

Experimental data has been produced showing charger efficiency from 49% to 77% (Kieldsen, et al., 2016) and 85.7% (Sears, et al., 2014). This is from the plug to the car.

The authors attribute these figures to value engineering of charging equipment to create readily affordable units rather than those capable of high efficiency. Further to this, Sears et al. state that “Under-dimensioned components cause higher heat dissipation that makes cooling necessary, which is an additional power consumption” meaning that in order to optimise charging efficiency, it is necessary to correctly specify components and software to reduce energy losses.

Sears et at. also states “A power converter with an efficiency of 95 % have a decrease in efficiency of 10 % when operating at half the nominal power”. It is apparent that in order to be able to advertise minimal charging duration, it is necessary to have a high charging capacity i.e.,43kW (63A, 400V) “rapid chargers”. The availability of these charging points is relatively low with only 21.3% of publicly available charging points being able to support ≥63A (Department for Transport, 2021_h). Thus, the majority of charging that will take place, especially for those who charge at home using a standard 13, 16 or 32 amp connection, will incur significant charging losses due to being below the designed peak efficiency of the charger.

If the experimentally derived charger efficiency data are applied to the manufacturer energy consumption figures, the energy usage “from the grid” can be calculated:

Furthermore, the major source of electricity generation in the UK is from burning fossil fuels, namely oil, gas and coal (Department for Business, Energy & Industrial Strategy, 2020_a) (Figure 5). The thermal efficiencies of these generating plant are shown in Figure 6. When the thermal efficiency data are normalised to generation source data, the net efficiency of UK generating plant equates to 43.29%. The rest of the fuel energy is lost to conversion, transmission and distribution. (Digest of United Kingdon Energy Statistics (DUKES), 2020_b).

The total net efficiency for all electricity sources (including renewables) is 45.85%. Factoring the conversion efficiency from primary source i.e., fuel to plug, the net power usage for EV can be calculated:

Given that EV energy consumption data are gathered from manufacturer published test procedures such as the WLTP rather than real-world driving scenarios, it is reasonable to use the same data for ICEV vehicles which show 50.5 mpg for petrol ICEV and 57.9 mpg for diesel ICE (The International Council on Clean Transportation, 2018) and thus, 526.2 Wh/km and 503.92 Wh/km respectively. It is therefore immediately apparent that even in the best case of high charger efficiency, EV are only marginally more energy efficient per unit distance than diesel ICEV when the primary energy source is considered. Note that for this example, the energy required to move the primary fuel to it’s destination of use e.g. electricity plant or petrol station is not considered in the calculations, nor are the energy requirements of building plant and vehicles as they are outside the scope of this research.

I then go on to outline different methodologies of waste energy recovery including testing and evaluation procedures and apply the theoretical (yet realistic) outcome to a theoretical diesel engined car. I then calculate the effect of these technologies on the average power requirements to move it. RB = Regenerative Braking, EER = Exhaust Energy Recovery.

I then compare the power consumption of the "best case" for ICE + waste energy capture against the average EV manufacturer data, charger loss normalised data and calculated "primary source" data.

We see that once primary fuel for electricity generation and charger losses are taken in to account, that both urban and extra urban diesel hybrid models are favourable in terms of power consumption.

Anyway, that's about the nub of it. Apologies if it's a bit disjointed as I've just snipped out the top level stuff.

Interesting what you posted about energy losses @Gareth J . I've not read the report but I imagine that 20% loss isn't unreasonable. It would be interesting to see where these losses occur and how they impact the net power consumption of ICE and EV.



Edit: I don't seem to be able to delete the three images above (repeats) so I've just made them really small.

 

[Gareth J]

Interesting what you posted about energy losses @Gareth J . I've not read the report but I imagine that 20% loss isn't unreasonable. It would be interesting to see where these losses occur and how they impact the net power consumption of ICE and EV.

My point being, that you seem to have accounted for a lot of those losses when looking at BEVs, but not included them for Petrol/Diesel fuel. The colours of the charts give rough breakdowns of energy expendatures. The most energy intensive listed as "production and conditioning at source" (I read that as getting the oil out and leaving the guff behind) and "transforming near market" (I read that as refining).

 

[Gwil]

Where are people buying these solar PV panels (let alone cheap), seems to be slim pickings down here in the south west on eBay!

The diy chain Leroy Merlin have been offering 350w panels at 150 euros here. There's also a place in the UK called (I think) Bimble Solar.

 

[julianthegypsy]

The diy chain Leroy Merlin have been offering 350w panels at 150 euros here. There's also a place in the UK called (I think) Bimble Solar.

Bimble, I believe, do second hand panels. They do have an excellent reputation among the off grid community and I see them recommended frequently. They may do new panels too, I haven't checked their website for ages.