For the last couple of months I’ve been measuring the energy consumption of my electric bike. Most days I cycle to and from work, a distance of about 4.9 km each way with an elevation difference of about 110 m. I mostly use the electric assistance for the climb, although given a strong headwind I’ll use it on the flat. Each time I charge the bike up I’ve been noting down the distance travelled and the electricity required for a full recharge. Below is a graph of the total electrical energy used against the total distance travelled for the months March – April 2011.
📷
The regression line has a slope of 0.022 KWh/km. So for 1KWh of electricity I am travelling about 45 Km, or to put it another way I’m getting a consumption of 2.2 KWh per 100 Km . Supposing for a moment that I’m filling the bike up with petrol (energy content 35 MJ/l) this would convert to about 0.23 l of petrol per 100 km or about 434 km/l (2.2 KWh = 2.2 * 3.6 MJ = 2.2 * 3.6 /35 l of petrol).