Checking the carbon footprint of the National Grid

[MB]

I've written an online application that allows you to check the carbon footprint of the National Grid. The data feed is updated every five minutes and monitors the carbon footprint and the grid utilisation, and reports on what sort of power station is producing the energy (coal, gas, nuclear, etc.)

The system then recommends whether it is a good time to plug your car in to charge up or not.

There are tremendous fluctuations over a full 24 hour period - I've seen the carbon footprint go as high as 635g/kWh and drop as low as 270g/kWh. It depends on how much electricity is being demanded by the country - at the moment because its January and very cold, demand is higher than normal.

It all makes interesting reading. I'll be doing a mobile phone version of the application next month.

I'd appreciate any feedback.

http://www.owningelectriccar.com/nation ... ctric.html

[andylaurence]

Currently, it's showing 587g/kWh. That means, if my car did 5km/kWh, I'd be contributing similar emissions to a BMW 116d. That's a lot higher than I expected! I'd be better off with a Citroen C1 or a Mini Diesel than an EV today.

[ChrisB]

I'd appreciate any feedback.

Ah you've been playing with th NETA data then MB

I've seen a similar site doing this else where, what data point do you use to say its OK plug your EV in

ChrisB

[jonny]

Dont forget the CO2 to distill that fuel and for getting it to the petrol station.

Of course I guess then you have to account for tranmission losses and colombic efficiency of the battery.

Interesting to see those figures though.

[MB]

Currently, it's showing 587g/kWh. That means, if my car did 5km/kWh, I'd be contributing similar emissions to a BMW 116d. That's a lot higher than I expected! I'd be better off with a Citroen C1 or a Mini Diesel than an EV today.

Oh no you wouldn't. The chances are your ev is doing more than 5km/kWh. A lot more. Also, the figures that manufacturers quote for their cars doesn't exactly tell the whole story.

My Mitsubishi iMiEV is currently doing about 9km/kWh and my G-Wiz is doing around 10km/kWh. That is based on my driving too and from work, and that is a mixture of city centre driving and dual carriageways.

Take into account that although the manufacturers figures for an economical petrol/diesel car are often around the 100g/km mark, that isn't what you'll get in the same conditions that I'll get my measurements for my EVs. Real figures are likely to be 25-30% higher.

You need to be aware that the CO2/km calculations are based on 'tank to wheel' figures, not 'well to wheel' figures. If you take into account the extraction of oil from the ground and refining, the figures look very different again.

I've been doing a lot of research into this area, including some practical tests, measuring real world efficiencies of petrol and diesel cars and comparing them with electric cars. The results will be announced next month with the launch of my new book.

With regards to the figures I publish on that web site - they do take into account average transmission losses and the average carbon footprint for the supply of the raw materials and delivery to the power stations. So although it is an average, you're getting the full picture and not just the emissions from the power stations divided by the amount of electrickery they're producing.

[andylaurence]

It's a great resource. It's surprising to me that the figures are so high. I've no idea how many miles I'd get to one kwh but I do know that whilst your GWiz gets 10km/kWh, it doesn't get to anywhere near the national speed limit. I don't know which cycle they use to evaluate the CO2 emissions. Is it based on the combined cycle? Still, if you're only driving short distances at low speed, there's no doubt that an EV is both cheaper and makes better use of the energy it's supplied.

[geekygrilli]

Hi Mike

Very good information, nice and clear. As Chris B asks; at what point have you said its Ok to charge?

I remember when I was building my car I had a look at this information. I found that a coal fuelled power station produces approx 800g/kWh.

If my car used 250Wh/mile of electricity produced by coal, it'd be producing 200g/mile of CO2....more than my diesel Berlingo - I got a bit depressed at that point!

Best regards

Christopher

[timpootle]

You need to be aware that the CO2/km calculations are based on 'tank to wheel' figures, not 'well to wheel' figures. If you take into account the extraction of oil from the ground and refining, the figures look very different again.

I think that covers the disparity you have seen.

[MB]

Thanks for the feedback, guys. I really appreciate it.

Based on what has been said here, I decided I needed to have another go at the page in order to explain more clearly what the fuel savings actually are.

Go and have another look - I've added a new table on the bottom right hand side that shows what the carbon footprint is for an electric car based on charging the car using the current electricity supply, expressed as g/km, and then compared this to a number of different small petrol and diesel cars you can currently buy.

Here's the link again: http://www.owningelectriccar.com/nation ... ctric.html

My calculation as to whether or not now is a good time to charge up depends on various factors, including the current carbon footprint, the time of day, the grid utilisation and a prediction as to what is going to happen next based on observations from previous days. It also takes into account how much power is being generated by hydro and wind. It is not a simple algorythm.

[ChrisB]

Go and have another look - I've added a new table on the bottom right hand side that shows what the carbon footprint is for an electric car based on charging the car using the current electricity supply, expressed as g/km, and then compared this to a number of different small petrol and diesel cars you can currently buy..

Theres no Berlingo/Pug 106 in the list MB

My calculation as to whether or not now is a good time to charge up depends on various factors, including the current carbon footprint, the time of day, the grid utilisation and a prediction as to what is going to happen next based on observations from previous days. It also takes into account how much power is being generated by hydro and wind. It is not a simple algorythm.

So its your own algorythm ???

Must admit I've yet to see the system saying I can plug my EV in to charge without causing a imminent gloabal disaster but I expect its late at night early hours of the morning.

ChrisB