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The True Impact of EVs
Roger Bryant
378 Posts

An interesting piece from The Engineer comparing the whole life energy costs of a Polestar and the equivalent petrol Volvo. There are obviously a number of assumptions that can be challenged but it tends to support my current view that replacing my 13 year old diesel with  an EV does not yet make sense.



The comments also raise some interesting points.

8 Replies

You might like to have a look at the recording of the webinar we ran last month, entitled ‘Schrödinger’s Car, are Hybrids a Real or Imaginary solution ?'  Our presenter, Nick Molden, a leading figure in the field of measuring vehicle emissions, showed the results of real-life testing of vehicles, which differ markedly from some of the official figures.  The conclusions and implications are interesting !

The link to the video on YouTube is here : 


3 Posts

Although I agree with the urgent need to switch production of new cars to EV's, my understanding is that currently buying a 2nd hand petrol has less environmental impact than buying a new EV.

It is interesting to watch the recording of the Surrey Webinar on Hybrid vehicle emissions, which deals with the whole-life carbon cost.
The link to the video is : 
8 Posts

Thanks for the talk, that was excellent.

In my view a couple of areas missed:

If most drives are less than 5km (i.e. 3m) then people should walk or cycle unless time obviates it.

SUVs cause problems in car parks which results in additional CO2 emissions from other cars.

A hybrid  car also charges the battery when coasting downhill or braking. Any CO2 involved in the charging of the battery is recovered (abit) when the battery is used.

As a petrolhead, I'm a fan of Harry's Garage U Tube videos, so please forgive my bias and take a look at.

Whilst I favour electric vehicles in heavily populated cities where local pollution is a known cause of serious health issues the argument for banning ICE vehicles completely is flawed.  Various studies have estimated the carbon break-even mileage of an EV to be between 50,000 and 100,000 miles and ironically this is about the same as the average mileage of cars before they are scrapped.  On top of that, EVs are not zero emission, as Harry explains, since they rely on electricity which is mostly generated by burning fossil fuels - depending on where you live the carbon emissions of an EV vary roughly between 40% and 110% of the equivalent ICE vehicle.  Fair enough, if all electricity generation was zero emission, which it may eventually be, then there is a credible argument for supportiing EVs.  But with the ever increasing need for electricity to charge EVs, this is not likely to happen by 2030.  Even the newly approved Rolls Royce nuclear power plants are unlikely to be available by 2030 and we all know, wind generators don't really help, as conventional power stations are all running at sub-optimal efficiency ready to pick up the slack when the wind drops.

I was angry when the UK government advocated and even supported the purchase of diesel cars over petrol because I know that the pollution from diesel vehicles is worse.  And, in usual fashion, when they finally realise the error, there is talk of subsidy for people to replace diesel cars but no compensation for those who chose to incur the extra cost of buying petrol cars.  I wonder how long it will take for them to wake up to the mis-information about EVs.

3 Posts
Whilst it's always interesting to listen to alternative views on YouTube, ultimately I think we should be listening to the scientists. Having said that, here's a video from an American petrolhead evaluating the environmental impact of EV's vs ICE's:
8 Posts

My first car (petrol), in the 80s, did about 30 miles per gallon. I now have a Toyota Hybrid that can do 1 mile on battery. With this car, I can do just over 60 miles per gallon of petrol. The best I have achieved is 64 miles per gallon. This is a massive improvement. If we could further improve the efficiency of petrol based hybrid cars by around 40% then we could achieve our CO2 targets. The alternative would be to replace petrol with hydrogen but keep hybrid cars.

When I was working it did around 6,000 miles per year. I generally keep a car for 10 years from new as that is when, in my experience, problems start. This is 60, 000 miles in total. Now I am retired, I try to walk most places and only use the car for further away places. This means I use the car around once per month and cover around 2,000 miles per year. I fill up with petrol 3 or 4 times per year.

When driving, I try and avoid accelerating up hills while achieving the road speed going down hill. If I am at speed, then I use the down hill to rechange the battery by coasting. For example, on motorways I try and overtake lorries going down hill. At junctions, I try and start breaking quite early so that, again, the battery charges up.

I watched the Schrodinger's Car video. That seemed to be based on a large amount of research, i.e. science.

8 Posts

Is anyone with knowledge talking to the government about this?

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