Started October 2009. Charts updated June 2017
I'm playing with the CarbonZero household calculator to calculate the monthy greenhouse gas emissions for our household.
The calculator asks for either a monthly or yearly value for various consumption types:
The end result for September 2009 was: 172 kg estimated total CO2e emissions. They provide the ability to instantly buy high quality New Zealand based offsets for $28.75 per tonne (1000 kg) [as at 4 Feb 2015]. [The market price for NZU carbon credits is much lower, but that's for bundles of 100 units or more of variable quality. CarbonZero is one of the few (only?) places you can buy single NZU carbon credits.]
Then I added in data for every month going back to January 2004.
What is most useful about this exercise is the graph below. The spikes are almost all car related - holidays to see friends and relatives. In January 2009 my business had a cash-flow crises so we went cycle touring rather than drive to family. Then in June-July a friend lent us their grunty car and we enjoyed the convenience - a lot.
In 2011 a close family member had cancer which resulted in us travelling a lot more - so our transport related emissions went way up.
In January 2014 we went on a two week, 2319 km driving holiday around the South Island resulting in 551 kg CO2e emissions. A bit of a carbon blow out. For comparison; return flights to Sydney for the three of us (4446 km each) would have resulted in 3078 kg CO2e emissions.
In February 2014 I got an electric commuter bicycle which my public transport use. Over the previous few years I had been catching the bus/train home frequently with my folding bike.
Note: the above graph is per adult. Our son is 7 years old so his carbon is all our responsibility.
The table below gives emissions per person - that's to make it easier to compare against the country based emissions data. However - that's an unfair comparison because the CarbonZero measurement leaves out food and other consumption.
|Year||Our household kg CO2-e emissions||Our kg CO2-e emissions per person|
|Country||kg CO2-e per person|
Source: http://en.wikipedia.org/wiki/List_of_countries_by_greenhouse_gas_emissions_per_capita) 2005 data. Note that these country numbers are just the national total carbon emissions (including agriculture and industry, etc) divided by the population. I don't know what the average New Zealand household emissions are - so it's a bit unfair to compare them.
There are a lot of qualifications needed at this stage:
I don't mind if the calculator is not perfect at this stage, and I don't mind that my previous data was lacking. It's a step in the right direction. The more I do this the better at it I'll get.
My next steps:
I'm not sure where Mr Spratt got these numbers from - the Australian number doesn't match up with the IEA number in the chart above. And he doesn't say if he's talking about carbon emissions or CO2 equivalent emissions. I'd love to have a robust estimate of the global capacity to absorb carbon. I'll keep looking.