What is our limit?

What is our limit?

Monday, September 14, 2015

What is our carbon footprint?

This week, i chanced upon a book that proved to be an interesting read - 'How bad are bananas' by Mike Berners-Lee in 2010.
(Retrieved from Google images)

Basically, the book gives readers a sense of the carbon impact of everything we do and think about, or rather a carbon instinct. He mentioned that the average UK person currently has an annual carbon footprint of around 15 tonnes (which is equivalent to 15 thousand kilograms worth of carbon). I thought that this book was rather insightful and hence for this post, i'd cover some of the more interesting activities that he has mentioned :)

  • Drying your hands

Zero CO2 letting them drip
3g CO2 using an Airblade
10g CO2 using a paper towel
20g CO2 using a standard electric drier

Ever wondered how you should dry your hands after visiting the public toilet? A hand dryer or a paper towel ? As you can see, a hand dryer that produces heat emits double the carbon emissions as compared to a paper towel. The reason why a standard drier produces comparatively more carbon emissions is because it always take up a lot of energy to heat things. Personally, i'd just wipe it on my clothes :p

  • A plastic carrier bag
3g CO2 with very lightweight variety
10g CO2 with standard disposable supermarket bag
50g CO2 with heavyweight, reusable variety

That would actually be 2.5kg per year if you use five standard bags per week: about the same as one large cheeseburger. 
Better alternatives that can function as a plastic bag are rucksacks, wheelie baskets, or reusable bags (that has to be efficiently used and not be disposed of easily)
  • A paper carrier bag
I always had the impression that paper bags produce lower carbon as compared to plastic (ever since Mcdonalds started using paper carrier bags instead of plastic ones), but it turns out that i was wrong. The paper industry is actually highly energy intensive. In fact, if we were given a choice between plastic and paper, the plastic one is a better alternative.

12g CO2 if recycled and lightweight
80g CO2 if it is an elaborate bag from mainly virgin paper as supplied by many clothing retailers

The author also mentioned that unless we recycle our paper bag, it is likely to end up in the landfill, where it will rot and emit more CO2 and even worse, methane. Typically, there will be around 500g of greenhouse gas emissions per kilo of paper buried.

  • A shower
90g CO2 ( 3 minutes, efficient gas boiler, aerated shower head)
500g CO2 ( 6 minutes in a typical electric shower)
1.7kg of CO2 (15 minutes in an 11-kilowatt electric power shower)

If you have high-carbon shower habits, there could be half a tonne per year to be saved here - equivalent to a return flight from London to Madrid. Apparently, an aerated shower head helps to make less water feel like more. In theory, it would help to save water and carbon without you having to forgo any comfort.

  • Burger
A burger actually produces much more carbon emissions than what you think - think twice before you eat one!!

1kg CO2 for a veggieburger
2.5kg CO2 for a 4-ounce cheese burger

Animal produce tends to be more carbon intensive than vegetables and grains because animals consume a lot of energy just to keep themselves warm and move around. Beef and dairy farming also poses a problem as cows, like sheep, are ruminants. These animals give out methane, a greenhouse gas 23 times more potent than CO2. 
Demand for meat also provides an incentive for deforestation because it raises the demand for grazing lands.

(Retrieved from http://sustainontario.com/wp2011/wp-content//uploads/2011/01/Hughes-Steven-Food-.jpg 
(Unfortunately there is a discrepancy of the numerical quantity between the picture and the book, but i hope the picture gives you a clearer picture of how much carbon emissions the production of a burger gives off)

That said, maybe we should all turn vegetarian ??? haha just kidding, i can't turn away from meat just yet...but i guess i'd cut down on my beef intake from now onwards .. 

  • Leaving the lights on
90kg CO2 on a low-energy bulb for 1 year
500kg CO2 on a 100 watt incandescent bulb for 1 year

Having an average of one bulb turned on unnecessarily at any one time is almost certainly quite common - some people even sleep with their lights on because they are scared of the dark! As for public places such as toilets, i suggest that we invest in better technology such as the automatic light sensor to reduce such wasted carbon emissions.

And exactly how bad are bananas? You'll have to read the book yourself to find out! 
Till next time, 
Mu Rong

Mike Berners-Lee (2010) How bad are bananas? Great Britain. Profile Broks LTD.

1 comment:

  1. Haha, I really liked reading this post! It was interesting in terms of how you gave insight on how our daily activities such as just simply drying our hands or eating a cheeseburger could actually produce so much carbon dioxide in the process. Especially for the use of plastic bags in supermarkets, I think that most people still do not bring their own recyclable bag to supermarkets because it might be inconvenient or they are just lazy, resulting in unnecessary use of plastic bags. Sometimes, heavy items such as rice could also result in the use of double plastic bags, or that fresh produce such as meat would have to be placed separately from other groceries. I feel that in curbing this "problem" of using plastic bags in supermarket, maybe singapore could model other countries such as Malaysia, where on Saturdays, they would not provide any plastic bags at all and people would have to either bring their own bag or pay for the plastic bags. Even in Hong Kong, they have recently started charging 50cents for a plastic bag. (yet in singapore, it is charged at 10cents). One possible solution could be to raise the price of plastic bags, so that the higher price would deter people from taking plastic bags and encourage them to bring their own bags in the future.