beer

Since energy is a topic of conversation in our office, and I have been doing some bicycle commuting, it suddenly became important to have a table of transportation energy use.

Conclusions:

• Bicycle wins the efficiency contest.
• Electric car could win the efficiency contest if you fit 5+ people in your car.
• Escalating that war, the tandem would probably be the next weapon of choice.
• Trains are pretty good (no surprise), and perhaps could get better with regenerative braking.

Assumptions:

• Bicycle uses 50 kcal/mile
• 747 90 mpg (FAA figure is lower,but…)
• Electric car: .25 kwh/mile (from Tesla  if you trust software ‘geniuses’  posing as a car company, or if you trust the old fashioned car company GM, their ‘Volt’ appears to be .34 kW-h/mile)
• <rant> Tesla presents data like a software vendor (no surprise).  Their claim a 70amp @220 volt charger, running for 3.5 hours charges the battery fully (capacity listed as 55kw-h). Energy = efficiency (always less than 1.0) x 70 x 220 x 3.5 = 53.9. Clearly credibility = 1/ efficiency </rant>
• SUV 15 mpg
• Train (swiss) .082kwh/passenger-mile
• Pint of beer has 220 kcal
• kcal (kilocalories) are the kind we eat (aka Calories with a big ‘C’)  Yep, our system of measurement is THAT stupid. Small calories x1000 = Calories =  kilocalories.

Conversion Notes:

• It’s assumed that all liquid fuels have the same energy content as gasoline: 36.6 kwh/ gallon.
• Liquid fuels have crappy energy conversion, unlike electricity which can be 100% efficient.