A few weeks back I made the wager in a light-hearted Facebook discussion that my electric car was cheaper on a 15 mile round trip than jogging that same distance powered by Jaffa Cakes. (The discussion made more sense if you were there.)
Why Jaffa Cakes ? Well, ‘cos my fine, feathered Irish friend happens to be obsessed with them. Go figure.
So here are the maths, proving once and for all that Electric Car > Jaffa Cakes.
I’ve done over 1,500 electric miles in my Zoe now, and have settled into an average consumption of 3.8 mpkWh (miles per kilowatt-hour). This is a combination of Eco-mode careful driving and foot-down enjoying-electric-torque screw-the-range-anxiety driving.
My current electricity provider charges £0.0809 per kilowatt-hour (8.09p) at the night-rate tariff (when I normally charge). I am considering moving over to green energy company Ecotricity with an even lower night tariff of 6.53p, with the added benefit of all electricity being generated from wind, sun and sea – but for the purposes of this calc, we’ll stick with the 8.09p tariff.
This gives us a very easy calculation for the 15 mile round trip:
15 miles / 3.8 mpkWh * 8.09p = 32p
Easy peasy – it cost me £0.32 for the trip in my electric Renault Zoe, at mid-market prices without even using the cheapest green electricity provider available. The round trip (with pickup stop) took me 26 minutes.
So, how much to do this powered by Jaffa Cakes ?
Let’s work on a rather leisurely pace to accommodate my Jaffa-cake-munching mate, giving him a whole 3 hours to complete the trip, at around 12 minutes per mile. Using the RunnersWorld calories burned calculator, this 15 mile jog over 3 hours should elicit a calorie burn rate of 126.71 calories per mile, for a total calorie cost of 1,901 calories.
Jaffa Cakes’ UK site kindly informs us that each Jaffa Cake munched will provide a wholesome 46 calories per cake (in addition to the standard delicious, taste-bud-tickling goodness). Our nutritionally minded friends at Tescos concur.
So, we would need 1,901 / 46 = 41.32 Jaffa Cakes to complete the arduous journey on foot (assuming a 100% efficient digestive system and no energy consumed by actually consuming the Jaffa Cakes – chew slowly mate).
Said Irish Jaffa Cake fanatic also runs a Jaffa Cake price tracking site (I kid you not), providing a handy reference to the live Jaffa Cake market price. At the time of writing, the best deal (per-cake pricing) on Jaffa Cakes would be the Twin Pack (24 cake) deal at Asda, going for the princely sum of £1.00 per twin pack.
Our cost of the trip powered by Jaffa Cakes would therefore be:
(£1.00/24) * 41.32 = £1.72
So there you have it. A mere £0.32 and 26 minutes in an electric car, and a wallet-busting £1.72 and 3 hours on Irish legs powered by Jaffa Cakes.
Clearly, electric cars are 5.39 times better than Jaffa Cakes.
I rest my case.