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BEV emmissions
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Great Ape:An electric motor is more efficient than a petrol motor
A BEV is about the same efficiency as an efficient ICE car
It's more efficent, and can be much more efficient, if we clean up our grids. It's already spitting out less CO2 by your own numbers.Nobody care about the efficiency of an electric motor Vs a petrol motor
You see, I, and may others, do. You speak very much like someone who has never driven an EV. Why would most people want to carry around a mini power station with all that noise and maintenance, when a nice quiet efficient electric motor and battery can do the job as well, or better? Reminder, I'm a petrol head and EV driver, I enjoy my petrol car, but school run mum should be nowhere near one.Please highlight where I have said this
Let me save you some time... nowhere
You count against in your 'calculations and estimations' never for.But it is true all a hybrid runs on is petrol
A hybrid can be higher or lower efficiency Vs a pure ICE car it depends on the design of the two
Bingo. Electrical storage makes a hybrid more efficient than an ICE. Electrical storage in an EV, however, is somehow not allowed to count!!Sure but this is an empty statement because we car talking about cars and primary energy efficiency. Not about one part of the system. It's like me saying the electric motor on the window of the corolla is more efficient than the electric motor on the window of the Zoe....so what?
It's really not an empty statement. The fuel source moves, and can be changed to be cleaner. I can't go around installing solar, hydro, wind everywhere, but the government can.That is a measure of carbon emmissions not efficiency
Sure, but it was a comparison you brought up, I had to fix your figures, and you've moved onto a different metric, 'efficiency'. I've already stated that petrol is a brilliant, energy dense liquid. It's very 'efficient', as in lots of kWh, per litre or whatever. But more than half of that is thrown away as heat, sound etc. That's not what I call 'efficient'. The EV, powered by a clean grid is more efficient. You'll tell me 'the grid' is filthy, I say, clean it up!Energy efficiency is not the same as carbon emmissions
At least understand that before you go further
BEVs are roughly the same energy efficiency
In the UK they are a little less carbon emmissions
In most the word they are more carbon emmissions
Does that clear things up?
Sure, efficiency isn't emmissions, got it. Again, you brought up the carbon emmission numbers, which I argued with, and we've been talking about efficiency. The electric motor is more efficient than the ICE. FACT. Bring fuel into it. ICE power station only? Same emmissions. Bring renewables in, fewer emmissions.
A BEV is NOW more efficient than an ICE. It's only getting more efficient as grids clean up.and 5-20% charging a car and
We agreed on 90% charging efficiency.5-10% converting that DC to AC to kinetic
You've already been told that any inefficiencies you choose to dream up (and you've had a good few cracks) are already included in the m/kWh figures you're getting from the REAL USERS you insisted upon. Stop double counting.
SolarchaserAs an aside of sorts, the leaf is generally seen as a small car.... it's really not.
I call Leaf a Focus sized car - that's the 'small family car' category.
silverwhistleThanks for the account of actual experience with an EV. I'm waiting for SH prices to soften or more battery owned Zoes to become available
Sorry, there are very few around, they carry a significant price bump over the rented ones, obviously, and there will be even fewer 40kWh ones, vs demand. Renault need to get boatloads of battery rented Zoes landed on them, with no-one wanting to buy them (so no rental income), to make them do something about it.0 -
Renault need to get boatloads of battery rented Zoes landed on them, with no-one wanting to buy them (so no rental income), to make them do something about it.
Precisely. And with Renault apparently abandoning the lease model with the ZE50, that scenario is now much more likely.
Loving your work, by the way. :cool:Scott in Fife, 2.9kwp pv SSW facing, 2.7kw Fronius inverter installed Jan 2012 - 14.3kwh Seplos Mason battery storage with Lux ac controller - Renault Zoe 40kwh, Corsa-e 50kwh, Zappi EV charger and Octopus Go0 -
Sure but this is an empty statement because we car talking about cars and primary energy efficiency. Not about one part of the system. It's like me saying the electric motor on the window of the corolla is more efficient than the electric motor on the window of the Zoe....so what?
It's really not an empty statement. The fuel source moves, and can be changed to be cleaner. I can't go around installing solar, hydro, wind everywhere, but the government can.
This is just for fun, but might make people stop and think a bit.
Whilst the electric motors on both cars might be the same efficiency, be they an ICEV or BEV , we should consider (as you say) the fuel source.
For the ICEV, that will be the petrol, through the engine, then a power takeoff through the alternator and on to the window (or even via the battery too). If we assume for arguments sake that both window motors are 100% efficient (or any other figure, it's irrelevant), then the BEV will be operating the window at around 100% efficiency from the onboard fuel, whilst the ICEV will be doing it at something like 5-10% efficiency from the onboard fuel source. The same applies to the radio, lights, window defrost, etc..
The counterargument would be for heating, as the ICEV will make some use of one of the waste products (heat). Though for cooling the BEV wins again, both via electric fans, and/or A/C.Mart. Cardiff. 8.72 kWp PV systems (2.12 SSW 4.6 ESE & 2.0 WNW). 20kWh battery storage. Two A2A units for cleaner heating. Two BEV's for cleaner driving.
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
Martyn1981 wrote: »This is just for fun, but might make people stop and think a bit.
Whilst the electric motors on both cars might be the same efficiency, be they an ICEV or BEV , we should consider (as you say) the fuel source.
For the ICEV, that will be the petrol, through the engine, then a power takeoff through the alternator and on to the window (or even via the battery too). If we assume for arguments sake that both window motors are 100% efficient (or any other figure, it's irrelevant), then the BEV will be operating the window at around 100% efficiency from the onboard fuel, whilst the ICEV will be doing it at something like 5-10% efficiency from the onboard fuel source. The same applies to the radio, lights, window defrost, etc..
The counterargument would be for heating, as the ICEV will make some use of one of the waste products (heat). Though for cooling the BEV wins again, both via electric fans, and/or A/C.
The fuel efficiency to charge the car is only 27-38% efficient from power station to battery
That is to say 62-73% of the primary energy to charge the battery is lost as heat along the way
What remains is used efficiently but this original loss makes BEVs not very efficient taking all steps into account
When you do the sums you find a litre of petrol in an efficient ICE gets about the same mileage as a litre of petrol in a power station to charge a BEV
The counter argument is...well BEVs can be charged by wind or solar
And the counter argument to that is... well the world's big grids aren't close to zero fossil fuels and won't be for a long long time0 -
The fuel efficiency to charge the car is only 27-38% efficient
That is to say 62-73% of the primary energy to charge the car is lost as heat along the way
What remains is used efficiently but this original loss makes BEVs not very efficient taking all steps I to account
When you do the sums you find a litre of petrol in an efficient ICE gets about the same mileage as a litre of petrol in a power station to charge a BEV
The counter argument is...well BEVs can be charged by wind or solar
And the counter argument to that is... well the world's big grids aren't close to zero fossil fuels and won't be for a long long time4kWp (black/black) - Sofar Inverter - SSE(141°) - 30° pitch - North LincsInstalled June 2013 - PVGIS = 3400Sofar ME3000SP Inverter & 5 x Pylontech US2000B Plus & 3 x US2000C Batteries - 19.2kWh0 -
I fully get what you're saying about the emissions of a BEV at this moment in time. However, the lead time required to change the fleet to predominantly electric vehicles means we have to start now to have an outside chance of getting over 50% by 2030. The grid can play catch up ... but at least every extra kWh of green energy will have a home.
I understand what you are saying but what you and most people don't get is that the grid changes very slowly
Germany went from 5% renewables in 1995 and they hope to be 65% renewables in 2030
That is just a 1.7% conversation per year and Germany is a very wealthy country
The grid doesn't change fast
Let's say the average car lasts 15 years before it gets too tatty and is recycled
That means a BEV in Germany will be at least for the next 10 years coal powered predominantly and likely for the whole 15 years. It will result in more CO2 than an efficient hybrid
Also there is heating to solve
You don't need BEVs to integrate more green into the grid
Heating is bigger and 'easier' to solve
What makes more sense a £30 smart resistance heater to soak up excess wind or a £30,000 BEV to soak up excess wind?
Not only does the grid need to spend the next 10-20 years doing its ~1.7% a year conversation
It needs to spend another 10-20 years electrifying heating
Once all that is over BEVs might make sense
In fact even then they don't
Because a plug in hybrid with 30 miles can achieve 99% of miles electrified there isn't a necessity to go to 300 mile pure BEVs to cover the remaining 1%0 -
Looking more recently at Germany Google search says they were 17% in 2010 and aim to be 65% in 2030 that is a change of 2.4% per year
If the same rate can be maintained that means the German grid can be close to 100% net renewables in 2045 and this is assuming there is no significant electricity demand growth
If heating and transport is electrified on a large scale can they maintain 2.4% conversion per year?
And this is assuming the Germans actually hit their 2030 targets...they look like they will miss their 2020 targets and things will only get harder0 -
The UK plan is very significant if the UK can add a further 30GW of offshore wind in the 2020s that would be a conversion of 3.3% a year which is much more than Germany is planning but still only 3.3% a year... and not many countries have shallow offshore sites with good wind speeds
The Germans have started to protest against wind and grid expansion and their 2020 targets are going to be missed.
So this gives you an idea of speeds
Somewhere around 1.7% to 3.3% a year for committed countries with okay-good resources
Electrifying heating could double electricity demand
That alone would take 30 years to cover with wind power at the significant UK 2020s deployment rate
Ignoring any difficulty in grid or storage expansion
The child response is...just go faster
But things don't work out that easily
Significant infrastructure is never quick
Having said all this I don't see this as a failure I just accept it will take a very long time0 -
The UK plan is very significant if the UK can add a further 30GW of offshore wind in the 2020s that would be a conversion of 3.3% a year which is much more than Germany is planning but still only 3.3% a year... and not many countries have shallow offshore sites with good wind speeds
The Germans have started to protest against wind and grid expansion and their 2020 targets are going to be missed.
So this gives you an idea of speeds
Somewhere around 1.7% to 3.3% a year for committed countries with okay-good resources
Electrifying heating could double electricity demand
That alone would take 30 years to cover with wind power at the significant UK 2020s deployment rate
Ignoring any difficulty in grid or storage expansion
The child response is...just go faster
But things don't work out that easily
Significant infrastructure is never quick
Having said all this I don't see this as a failure I just accept it will take a very long time4kWp (black/black) - Sofar Inverter - SSE(141°) - 30° pitch - North LincsInstalled June 2013 - PVGIS = 3400Sofar ME3000SP Inverter & 5 x Pylontech US2000B Plus & 3 x US2000C Batteries - 19.2kWh0 -
The UK plan is very significant if the UK can add a further 30GW of offshore wind in the 2020s that would be a conversion of 3.3% a year which is much more than Germany is planning but still only 3.3% a year... and not many countries have shallow offshore sites with good wind speeds
Thought I'd comment on this as it is either a trick meant to mislead, or a complete failure to comprehend?
So, is 3.3% a small number, yes I suppose.
Is 3.3%pa a small number, no, not at all.
Is 3.3%pa everything, no, just the off-shore wind element.
So let's look at 3.3%pa over 10yrs, that would be, oh tricky maths, let me get my calculator ...... 3.3 ....... add your age ...... divide by the first number you think of ....... reverse 3.3 ....... and I think it's roughly 33%?
So, in the last decade we've gone from around 5% RE, to about 35% RE, and in the next decade we will hopefully add something like 37% (of current leccy demand (30GW off-shore wind @ 50cf / 40GW average UK demand)) just from off-shore wind alone.
Think about that, just a sniff of on-shore wind, PV, bio-energy and we'll be at about 80%.
As for cars (coming back to the BEV thread), we'll probably see a net increase in demand of about 10%, spread over 25yrs (0.4%pa average) if we get to 100% BEV sales in 10yrs plus the additional 15yrs to displace all the old ICE's.
Obviously the figure will be higher when we include commercial vehicles, but that's no problem, the more ICE to BEV's the more instant wins from the reduction in energy consumption and emissions.
Heating is a bigger problem, but again we need to consider energy in, which is gross FF, v's the roughly 3 COP of heat pumps running in the UK.
And then we need to include common sense and logic. Is there any scaleability issues regarding RE, nope, none at all. If we want to accelerate deployment we can, especially as costs are now approaching subsidy free, and the public awareness of both RE and AGW are growing rapidly.
Lastly, regarding the rather silly comment of off-shore wind and shallow waters, and ignoring the development of floating PV, which is going very well, can I remind folk of 'reality' again, and point out that whilst the UK has great off-shore wind potential, most countries aren't going down this route, and global calculations of RE generation always suggest PV as the main source, typically around 70%+ of global RE supply, and most countries can and will generate leccy from PV at far lower costs than the UK will from off-shore wind.
So nations will make best use of the RE that best suits them, be it wind, hydro, PV etc etc..
For those interested, be very careful when listening to comments about Germany and the rate of RE deployment v's CO2 reductions.
They are transitioning to RE at a very rapid rate, however, a lot of the RE generation is replacing nuclear generation, and they have increased leccy exports to Europe.
This graphic shows what they have achieved:
Obviously, as they start to run out of nuclear to displace, then their reductions on coal and lignite generation will accelerate. Again, German RE v's German CO2 reductions can be misleading if we don't look at the bigger, and long term picture of what they are doing and have achieved already.Mart. Cardiff. 8.72 kWp PV systems (2.12 SSW 4.6 ESE & 2.0 WNW). 20kWh battery storage. Two A2A units for cleaner heating. Two BEV's for cleaner driving.
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0
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