Have you calculated your carbon footprint at home yet?
It’s early February and already this year, parts of Australia have seen devastating bushfires, dust storms, smoke haze, giant hail and now floods.
Even if you didn’t believe in climate change, this wacky weather is enough to convince you to adopt the precautionary principle.
Of course lots of architects have publicly proclaimed they’ll go much further than that, by joining Architects Declare and pledging to make their practices carbon neutral this year.
I’ve adopted the same goals and sailed through the January 30 Green Power target, because we are entirely solar powered at home (where I work).
So now, in line with the target to conduct a carbon audit by June 30, I’ve turned my attention to the other parts of our household carbon footprint, and want to share what I found out.
According to this report on 1.5 degree lifestyles (which aligns with the Paris agreement reduction targets), households can reduce 75% of their overall greenhouse gas emissions by tackling just three key areas.
These are:
fossil fuel consumption;
diet and nutrition; and
car and plane travel.
The third category offers our family the greatest scope for improvement because our biggest GHG cost in 2019 was from flights. We travelled home from London on January 16; to Bali for my Mum’s 70th in September, and then to Japan on 18 December.
There is no possible justification for taking three overseas trips in a just-over 12 month period, but we did.
The upside is that we can drastically reduce our flight-related GHGs this year by holidaying closer to home (I’ve already booked a week at the beach for January 2021).
So we’ll save:
7 tonnes of GHG from London to Perth x 4 people (one way)
5 tonnes for Perth to Tokyo (also one way); and
2.72tonnes for Perth to Bali return.
Which - at 14.72 tonnes - is almost the same as our total consumption from cars, food and nutrition and fossil fuels at home, combined (14.84 tonnes)
I also travelled for work twice; to Sydney and Melbourne for meetings and the #collectiveagency conference (1.27t) and to Brisbane and Sydney for workshops and meetings (1.11t).
At this stage, I don’t have plans to travel to the east coast in 2020 but that may change and I’ll try and combine several trips into one, and offset any travel.
(For these flight emissions calculations - and to offset - I use Carbon Neutral Charitable Fund)
Luckily for me, the Institute conference is in Perth this year, but that just displaces the carbon cost onto other delegates, who are flying here to attend. I haven’t worked out how to enjoy the social and professional aspects of meeting and conferencing with colleagues and clients, without the hefty carbon footprint yet.
Next; our cars.
My husband drives an i30 from our house to Welshpool each day, accruing about 10,000 kilometres a year (unfortunately the public transport options are dismal for his commute - I think it would be three buses to cover about 20km). The annual GHG cost from his car is about 1.54t.
I drive an XTrail and rack up about 6600 km a year for a cost of 1.27 tonnes. Last year, I started catching the bus-and-train into the city for client meetings, which I intend to keep doing this year, to reduce my overall kilometres travelled.
I usually walk my youngest son to school in the morning (the oldest rides a bike) although I do collect him in the car in the afternoon. If I can convince him to ride a bike to school, we can potentially delete that afternoon trip to reduce car use.
Then, our fossil fuel consumption.
I’d long suspected - and my calculations bear this out - that we generate more solar power that goes unused and is therefore exported to the grid than we import. We’re in credit for the past two years of data, and we’ve had solar PV for the past nine years, so we’ve made some good GHG savings there.
We also have gas, which fuels our hot water and stovetop. I was surprised to find our annual expenditure is 3254 kWh (or units of gas) which equates to 0.65 tons of GHG (here in WA - the figures are different in each state/territory). On that basis, I don’t think it’s worth converting to all-electric - which would include an induction cooktop and electric hot water system - before those appliances need to be replaced.
We also use wood for heating in winter - I’m not sure how much and need to perform the calculation based on our heater (an efficient Norwegian combustion stove). I think our insulation is very poor though, and I am worried about the amount of heat lost from that, and via leaky windows and doors. That’s not an easy fix in a 1980s double-brick house with a tile roof, and I’m happy to take any suggestions you might have!
I was surprised to learn that the third biggest household savings can potentially derive from diet and nutrition, and even more surprised to find out that transport and food miles a small impact in comparison with the agricultural impacts of certain foods. Meat and dairy are the most intensive sectors, because of the methane emissions.
I don’t eat much dairy - I’m intolerant to it - so for me, the short takeaway is to eat less beef, which has twice the GHG cost of lamb, and four times the GHG cost of pork, chicken and fish.
Source: Our World in Data
Switching away from beef - which we eat once or twice a week - to consume it less than once a fortnight is a no-brainer. And last night, my husband put peas in the (lamb) taco mince to stretch it further. We’ll also aim to have two fully vegetarian meals a week.
This graph shows the impact of five different types of diets, ranging from meat lovers to vegans.
Source: Shrink that Footrpint
So cutting down - or eliminating meat (especially beef) - has the single biggest impact on food-related greenhouse gas emissions, which account for 25% of emissions globally. Eating more plant-based foods - locally sourced where possible to reduce food miles - also helps.
Last year, I started buying pantry staples from a bulk food store, so I can use my own jars and eschew single use plastic, and I take what little soft plastic we have back to Coles to recycle (although I get that the jury is still out on the efficacy of this method).
And last week - as I was in the midst of these calculations - we opted to go to a Thai restaurant rather than ordering takeaway, because I hate those plastic containers!
Having determined what our 2019 carbon emissions were - about 29.56tonne for our family of four (based on the three sectors outlined in the 1.5 degree report, this doesn’t include clothes or other consumables, data and telecom costs, etc), I feel like we have a better roadmap now to reduce our emissions in 2020.
I’m very happy to share what I’ve learned if you’d like more information. I’m thinking about putting together a spreadsheet for people to conduct their own household audit, with links to calculators and data sources, so let me know if you’d like a copy, either for yourself or your clients.