Only by saving every 10th wash, consumers could save 47 Megatons of CO2 and 4.5 billion cubic meters of fresh water on a global scale. And if we could wash half as much it turns out to be 235 megatons of CO2 and 22.5 billion cubic meters of water.
This is really an amazing low hanging fruit for reducing climate gases. There is probably also a lot of overkill in todays washings. Shirts just used for one day can probably be freshened with some fresh air on the balcony, sweat from sports equipments can just be rinsed with some cold water sometimes. All together, to save every 10th wash cannot be a big sacrifice but can make a big contribution in mitigating climate change and scarcity of fresh waters.
The laundry issue has only, so far, been discussed within the limits of the direct emissions/water consumptions for the washing machine. The ecological footprint is also quite high for manufacturing textiles and the washing will influence the turnover of textiles. It should therefore be relevant to bring in even the degradation of textiles due to washing into the fo tprint of washing.
This has been calculated by the Stockholm-based consultant company; re-profit.
Method for the calculations
The starting point has been that every laundry consumes; direct electricity and fresh water as well as indirect energy-related CO2 as well as water by shortening the life of the textiles. The savings potential for 10% and 50% of the total environmental impact has been reported as results.
Environmental impact from the washing machine
For the electricity consumption of laundry I have used the figure 1kg CO2 / kWh. This is partly due to the fact that the most expensive electricity (coal production) is saved first and that every saved kWh therefore means a reduced need for coal power. This line of reasoning is based on something called the “marginal effect” and has been launched by Professor emeritus Björn Karlsson at Linköping University. Nor is it particularly controversial for the global level, where coal and natural gas account for 60% of electricity production, while the absolute cheapest electricity generation comes from solar and wind power.
The total electricity consumption from washes globally is 51.1 TWh and the water consumption of 12.3 km3 according to published data.
Environmental impact from the textile
The total amount of CO2 and water needed to produce textiles is 1.2 GT / year and 93 billion m3 respectively, according to New Textiles Economy. On the basis of information from RISE, I have assumed that 35% (conservatively calculated) of the life of the textiles is shortened by washing.
Also about less wash: https://www.theguardian.com/lifeandstyle/2018/mar/31/less-laundry-less-often-how-to-lighten-the-washday-load-on-the-environment
Pakula, Christiane & Stamminger, Rainer. (2010). Electricity and water consumption for laundry washing by washing machine worldwide. Energy Efficiency. 3. 365-382. 10.1007/s12053-009-9072-8.
Ellen MacArthur Foundation, A new textiles economy: Redesigning fashion’s future,
Personal email correspondence with Ann-Charlotte Hanning, RISE 14th Oct 2019.
Magnus Hedenmark, consultant