My carbon footprint calculations

For clarity, I will explain how i am calculating my One Tonne of Carbon per Year lifestyle and what is my starting point.

Life is Art

I made the decision at 17 years old (1979) not to get a drivers licence. This means I have never owned a car and don’t drive. I organise my life around being car-free. As I have learnt more about the carbon footprint of flying, I have made the choice to be flight-free too. I could not even consider living on net carbon zero, without making these decisions.

My daily budget of 2.74Kg per day needs to be considered. At first I thought my choices were fairly low carbon, but simple things like washing up on an gas boiler, taking the tube or bus, eating cheese, buying anything air freighted, quickly consumes a large proportion of my net zero carbon daily budget. So I now dig a bit deeper into my choices and am learning to be more creative about how to enjoy life within that budget. My fridge is constantly switched on and represents 64g CO2 per day. A++fridge 94kwh per year x UK electric grid 250g kwh divided by 365 days = 64g per day

Transport options

The food I consume will be calculated separately to transport per the mile options. So just to let you know I won’t be separately carbon calculating swimming, walking, sex, cycling, gardening, dancing, singing, DIY, cleaning or brain activity! I have a 3 year old bicycle which will be used far more. And I will also walk further to conserve my budget. This is why

Walking – 0g per mile (I will be calculating food consumed separately)

Cycling – 3g per mile (I will be calculating food consumed separately)

Cycling Taxi – 36g per mile

Average London underground – 68g per mile ( Mike Berners-Lee)

London half full hybrid Routemaster bus journey – 46g per mile (Mike Berners- Lee)

Full 90 seater electric bus in the UK – 6g per mile

Intercity Standard class rail – 80g per mile (Mike Berners-Lee)

note: some electrified trains in France as little as 22g per mile

Shared e-scooter app – 202g per mile

Average car journey – 530g per mile (Mike Berners-Lee)

Rush hour or congested car journey – 1.2kg per mile (Mike Berners-Lee)

New car – 8-50 tonnes of embedded carbon (Mike Berners-Lee)

Data options

Data has an ‘invisible’ carbon footprint. 80% of all data transferred online is video data, with nearly 60% of that being online video, meaning streaming videos stored on a server and viewed remotely, via sites like Netflix, YouTube or Vimeo.

I don’t watch netflix or Vimeo but occasionally I watch YouTube and regularly watch iplayer. I need to reduce my consumption of data to keep within one tonne of carbon per year (net carbon zero) so I have bought a 2nd hand personal DVD player at 0.018 kWh (negligible carbon) and will borrow DVDs from my local library I have also invested in a 2nd hand wind up radio.

I tweet and email. I write blogs. I am not on Facebook but I use search engines. I read articles online. All of this needs to be calculated. Roaming data 3G 4G is much more carbon intensive than broadband wifi and device choice adds to the carbon footprint as indicated here by the carbon trust

Data carbon footprint of watching a football game of 90 minutes

Tablet on broadband – 0.06 – 0.38kg

Smartphone on broadband – 0.06-0.38kg

Tablet on 3G – 3.7kg

Smartphone on 3G -3.6kg

Plasma TV (42″) – 0.48kg

LCD TV (32″) – 0.35Kg

LED TV (45″) – 0.31Kg

Desktop PC on broadband – 0.42-0.75Kg

Laptop on broadband – 0.08-0.40Kg

Data carbon footprint of text, mobile phone call social media, search engines, email and browsing

Tweet – 0.02g

email – 4g – 50g – Mike Berners-Lee

google search – 0.2g

servers and network – 50g per hour

iplayer video on demand – 88g per hour

1GB of data uses about 5kWh of electricity

The carbon footprint of my blog

The average web page is now 2.9MB, over 30 times the size of the average web page in 2003. Data translates into energy and carbon emissions, so as designers and developers we can have a huge impact on emissions by designing more efficient web pages. I will try and minimise the carbon footprint of this website by

  1. Using less images and no video
  2. Compressing images and keep to black and white
  3. Delete unused files, pages and websites
  4. If in doubt, leave it out

Note: At the time of writing the UK electric grid is 250g per kWh

I am using Mike Berners-Lee book ‘How Bad are Bananas: The Carbon Footprint of Everything’ because the calculations are transparent and comprehensive