Creative Scientist

How bad are bananas?

The first step in order to change is to realize the need for change. Thinking about carbon footprint for a little while, I started making minute changes last year largely based on randomly gathered ideas I had about what is carbon efficient or not.

To progress further, I needed data. A good friend told me about this book How bad are bananas that comprises a hundred different items and their footprints. It turns out only some of my ideas were correct, and that my correctness was not correlated with my confidence level; I got surprised.

This is a must-read to whom want to dive a little bit deeper in the world of carbon footprint, and will provide easy yet powerful steps to reduce one energy consumption.

As for me, I realize that my random small efforts help, but a more thought-about plan would probably bring better results. Below are a couple of noteworthy information that will be extended in the future.


  • Base unit is carbon dioxide equivalent CO2e than encompass all greenhouse gas and normalize their impact
  • UK average 13tons/Co2e/person/year

    • Author propose to reduce to 10tons as need only small effort and would make situation better for the planet
  • My current small efforts

    • Shower every other day
    • Commute by bike and public transportation
    • I had no car until 2019
    • No beef or lamb
    • Reduce long distance transport
    • Avoid plane where possible
    • Use single-blade metal only razor blade
    • No packaging for soap and shampoo
    • Planned additional ones
    • Low car use, maybe 3000miles per year
    • Reduce dairy, no milk in coffee, oat milk in tea
    • Measure and offset carbon footprint of car, train and plane
    • Offset by paying for charity planting trees
  • Notes

    • This book is about carbon footprint only, there are many more dimensions when making life choice including pollution, efforts needed and other side-effects
    • ME –> It is all about reducing the day-to-day consumption as exceptional events are both very hard to quantify and rare
  • Food

    • Banana actually quite good at 480g Co2e/kg, no packaging, little farming energy, good nutritional content
    • Apple avg. 550g Co2e/kg - 60g for local seasonal, 271g UK apple, 185g New Zealand!
    • Fresh tomatoes in season 500g Co2e/kg but 20kgs Co2e/kg not in season!
    • Strawberries 600g Co2e/kg in season, 2.7kgs Co2e/kg otherwise
    • Orange 500g/kg but juice 3kgs Co2e/kg
    • Rice plantations emits methane, 20x more carbon footprint than potatoes
    • Only yearly available fresh fruit not grown artificially: bananas, apple, orange, pineapple
    • Conclusion is eat local and in season!
  • Electronics

    • Small TV 1hr/day 32kgs Co2e per year, not much
    • ME –> Apple laptop 2015 was 710kgs Co2e, 2019 model is 222kgs Co2e
    • Personal laptop 2hours per day about 200kgs Co2e per year if 2015 laptop kept 4 years
    • Plug power meter is only about £10, need to get one for more precise measurements
  • Hot drinks

    • Coffee/tea + water 40g Co2e
    • Coffee/tea + Milk 70g Co2e
    • Large cappuccino 235g Co2e
  • Nappies 550kg Co2e per child, washing reusable nappies not better for carbon

  • Plastic bags do not matter - 5bags/week for a year is equivalent to 1 cheeseburger or about 15kms in a car, about 2.5kgs Co2e