EV Insight CO2 estimate out by a factor of 10

The conversion I use is 1 kWh is equivalent to around 0.225 kg of CO2. My annual electricity usage (2456 kWh), in my estimation, results in about 560 kg of CO2 emissions. Obviously the conversion factor varies depending upon the source of the electricity. The 0.225 kg/kWh figure was an average for 2024.

Thanks for the reply BeePee. I agree with your estimate for CO2 emissions for EV’s.  The problem I think I have identified is at the other end.

I drive around 1000 miles a month. To save 1,700 kg CO2 compared to a Fiesta doing 1000 miles that car would have to emit over 1.7kg CO2 per mile. The worst of the latest Fiestas produce 114g/km CO2 or 182 g/mile. Over 1000 miles that’s 182 kg CO2. So I can’t have saved 1,700 kg.

Using your figures I estimate my EV, which uses about 220kWh to do 1000 miles. That figure is from my meter and includes charging losses (it’s a Hyundai Ioniq, they’re amazingly efficient). Using 225 g/kWh that gives emissions of 49.5 kg. So I make my estimated CO2 reduction to be 130 kg.

[If I may digress for a moment. I should have said that’s 130kg plus or minus 30kg. I deliberately didn't give the result as 182-49.5=132.5 because that suggests an accuracy that isn’t there. For one thing I used my average of 4.6 m/kWh for the whole year whereas in a warm month it’s more like 5.5. Also, while it’s proper to use the 225g/kWh figure, the consumption is from smart chargers which are strongly biased towards using lower carbon electricity. The real figure will be much lower but I don’t know of any reliable estimates. My guess is in the range 100-150 g/kWh for what it’s worth]

Anyway back to the point. Please don't think I am being critical. I think it’s great that you include these figures. What I am trying to say is that (for the reasons given) there is very likely an oversight somewhere in the calculation for the CO2 emissions for the petrol car you are using for comparison.

I’m sorry if it’s uncomfortable that I have to do this rather publicly. I am trying to be constructive. I hope you agree it undermines what you want to achieve by producing these numbers - lower carbon emissions, less climate change etc. - if the numbers themselves are not reliable. 

Morning ​@springswood and thank you for your post.

No need for any apologies, we value feedback from our customers for everything - it’s vital for us to give the best possible customer experience 😁.

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