Well, clearly not as we all know that cycling's infinitely cheaper in most respects, however..
Since justifying the purchase of my Fuji for utility rides earlier in the year I've been keeping a record of the journeys I do that otherwise would have been done in the car; and how much I've saved in petrol.
So far, two months in and I'm winning to the tune of anywhere between £13 and £19 saved in fuel... heady stuff indeed!
The process did set me wondering about the actual, energy cost of cycling - when offsetting a ride against fuel we all make the assumption that the riding's free, when of course energy is expended to propel my ample frame through the air - and like everything else in our grotty, consumptive society this costs money.
My faithful Civic typically manages around 45mpg; so at £1.65 per litre this is about 16.5p/mile. According to the internetz 1 litre of petrol contains around 31 Megajoules (MJ) of energy, so at around 10 miles / litre each mile is costing me around 3.1MJ. Conversely, on the bike I seem to average around 50Kcal (or around 210KJ) per mile. So... in terms of energy efficiency, it takes about fifteen times less energy to drag my arse to the shop on the bike than it does in the car.
This leads us on to the question of how much the energy expend on the bike is costing. Apparently one 50g Mars bar - at around £0.60 street value - contains about 230kcal of energy. On paper enough to propel me around 4.5 miles at a cost of around 13p/mile.
Taking a more relevant food choice, a decent grilled noshup in the house of Wafter might consist of 2x eggs (150g, £0.50, 150kcal), 2x slices of hippie GF bread (50g, £0.50, 150kcal) and 3x fat butcher's sausages (200g, £1.50, 450kcal). That's a total of around 750kcal for £2.50 outlay, or around 300kcal /£1 / 17p/mile.
Of course none of this takes into account the intricacies of physiological efficency (for every 1 mars bar consume you might output 0.7 mars bars worth of physical effort) or other sources of error (bite me, it's been twenty years since I had to write a proper paper).
Likewise, of course it also fails to take into account the other benefits of cycling (reduced immediate pollution, maintence and sunk vehicle cost; both financial and material).. plus of course the infinitely reduced desire to jump in front of a train post-ride; from which some us benefit.
In summary, absolutely not a reason to discourage anyone from the joys of utility riding; but perhaps a sobering reminder that despite how some of us try to escape we're all caught in the hamster wheel one way or another
Since justifying the purchase of my Fuji for utility rides earlier in the year I've been keeping a record of the journeys I do that otherwise would have been done in the car; and how much I've saved in petrol.
So far, two months in and I'm winning to the tune of anywhere between £13 and £19 saved in fuel... heady stuff indeed!
The process did set me wondering about the actual, energy cost of cycling - when offsetting a ride against fuel we all make the assumption that the riding's free, when of course energy is expended to propel my ample frame through the air - and like everything else in our grotty, consumptive society this costs money.
My faithful Civic typically manages around 45mpg; so at £1.65 per litre this is about 16.5p/mile. According to the internetz 1 litre of petrol contains around 31 Megajoules (MJ) of energy, so at around 10 miles / litre each mile is costing me around 3.1MJ. Conversely, on the bike I seem to average around 50Kcal (or around 210KJ) per mile. So... in terms of energy efficiency, it takes about fifteen times less energy to drag my arse to the shop on the bike than it does in the car.
This leads us on to the question of how much the energy expend on the bike is costing. Apparently one 50g Mars bar - at around £0.60 street value - contains about 230kcal of energy. On paper enough to propel me around 4.5 miles at a cost of around 13p/mile.
Taking a more relevant food choice, a decent grilled noshup in the house of Wafter might consist of 2x eggs (150g, £0.50, 150kcal), 2x slices of hippie GF bread (50g, £0.50, 150kcal) and 3x fat butcher's sausages (200g, £1.50, 450kcal). That's a total of around 750kcal for £2.50 outlay, or around 300kcal /£1 / 17p/mile.
Of course none of this takes into account the intricacies of physiological efficency (for every 1 mars bar consume you might output 0.7 mars bars worth of physical effort) or other sources of error (bite me, it's been twenty years since I had to write a proper paper).
Likewise, of course it also fails to take into account the other benefits of cycling (reduced immediate pollution, maintence and sunk vehicle cost; both financial and material).. plus of course the infinitely reduced desire to jump in front of a train post-ride; from which some us benefit.
In summary, absolutely not a reason to discourage anyone from the joys of utility riding; but perhaps a sobering reminder that despite how some of us try to escape we're all caught in the hamster wheel one way or another
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