Calculating the impact from things you use
How many items of clothing do you buy new every year?
To determine the impact of clothing we looked to find a baseline of KG of clothes bought by each person each year. We used Statistica Data to establish that the average number of pieces of clothing were 33 pieces. We then found data on the average weight of clothing items from Parcl - averaged this data getting a value of 0.94KG per item of clothing. This was then used it as a multiple to establish the average weight of 31kg.
A value was then used to determine the weight of clothes for purchasing:
- 0-10: 4.75
- 10-20: 14.75
- 20-30: 23.75
- 30-40 (average): 33.25
- 40-50: 42.75
- 50-60: 52.5
- 60+: 71.25
How many pairs of shoes do you buy new every year?
We could find much data on the average number of shoes bought so we used data in an article from Sun which identified in Britain we buy on average 3 pairs of shoes (welcome other suggestions 
).
To establish the weight of shoes (and for all other assumptions) about environmental impact we found this very useful life-cycle assessment that gave an average value of 1 KG per pair of shoes.
This meant that the number of shoes = the KG value.
On average every week how much do you spend on non food or drink household items? (including health and beauty products)
We needed to find a value of waste from these items, which was difficult to find. We therefore made some very broad assumptions. For each £5 there would be 0.1KG of waste - which assumed the average weight of a bottle is 20grammes and you would get 5 bottles (e.g. detergent/bleach) for your money. This meant each of the steps in value were given a multiple against 0.1.
On average every week much time do you spend out of the house using facilities for leisure activities?
This was used for carbon emissions. We assumed for each hour in a leisure facility you would use 2.73kWhrs per day (which is equivalent to being at home) and then used the assumption that 10 hours in a leisure facility equalled the energy use of a single day at home. We then multiplied this against the carbon emissions from using gas heating 0.316 (as used for homes). The calculation was:
(Number of hours x 52 (weeks))/10 x (0.316 x 2.73) = 8.971 kgCO2e (for two hours)
This then gave a kgCO2e per hour spent in a leisure facility:
- 1-3 hrs: 9
- 4-6 hrs: 22
- 6-9 hrs: 31
- 9-12 hrs: 50
- 12-15 hrs: 60
- 15@ hrs: 90
How many nights a year do you stay at a hotel or resort for leisure purposes?
We used this to also determine carbon emissions. The assumption was broad saying that for a night in a hotel you would use more than what you would use at home, we assumed a value of 3kWhrs to stay at a hotel @ 0.316KGCO2 per kWhrs (gas heating). The values there were:
- 1-10: 4.74
- 10-20: 14.22
- 20-30: 23.7
- 30-40: 33.18
- 40-50: 42.66
- 50+: 56.88
What of the following technological items do you have in your house?
These were difficult values to find but we did manage to truth the majority of them against lifecycle assessments. Each of these was given a value of 1 which we then multipled this against to get KG of waste and KG of CO2.
| Manufacturing | Annual | Lifetime | Total Carbon emissions | KG Waste | KG Waste Each Year | |
|---|---|---|---|---|---|---|
| TV | 300 | 52 | 8 | 89.5 | 7 | 0.875 |
| Washing machine | 240 | 10 | 24 | 77 | 7.7 | |
| Laptop | 71 | 7 | 10.14285714 | 2.3 | 0.3285714286 | |
| Tablet | 80 | 7 | 11.42857143 | 0.59 | 0.08428571429 | |
| Home desktop | 7 | 15 | 7 | 1 | ||
| Power tools | 16.22 | 7 | 2.317142857 | 4 | 0.5714285714 | |
| Hair dryer | 16.22 | 7 | 2.317142857 | 1 | 0.1428571429 | |
| Sound system | 71 | 7 | 10.14285714 | 7 | 1 | |
| Home printer | 2 | 18.3 | 3 | 1.5 | ||
| Mobile phone | 31 | 15.7 | 5 | 21.9 | 0.14 | 0.028 |
What best describes your attitude to technology?
This gave a multiple we’d use to establish KG of Waste and KGCO2 from each of the items a respondent gave to the above question. We gave the following values:
- I use it until it dies: 1.3
- Where possible I will get items fixed to extend their life: 1
- I look for opportunities to upgrade devices before their lifetime is up: 1.6
- I’m a techno junky - I love using and buying new stuff: 1.9
Do you do any of the following to reduce your impacts from things you buy?
Some broad values (some only proofed I’m afraid (links below)) were used to give a calculation as a reduction factor against the particular answer to an above question:
- Buy clothes from ethical sources: 0.7 (multiplier)
- Buy shoes from ethical sources: 0.7 (multiplier)
- Use my clothes and shoes as long as poss then exchange: 1.5 (division factor)
- I buy second hand clothes: 1.3 (division factor)
- Use re-usable nappies for my children: 0.15 (as a multiplier to establish t of waste reduced (from life cycle assessment source))
- Use refillable coffee cup: 0.07 (as a multiplier to establish t of waste reduced (from life cycle assessment source))
- Avoid buying short lived disposable produce: 0.1 (as a multiplier)
- Use refillable or non plastic packaged products: 0.1
- Stay in eco friendly resorts and hotels: 0.5 (used for carbon reductions from staying at hotel)
Annual impact from things you use
To get any of the values above we established a ‘Things you buy weight’ and 'Things you buy carbon emissions), which is for all of the technological items. We used values from the table above to give a weight:
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Things you buy weight (KG): ( TV - F521033 *0.875+ Dishwasher *7.7+ Washing machine *7.7+ Laptop - F521070 *0.32+ Tablet - F521072 *0.08+ Home desktop comp… *1+ Power tools *0.57+ Hair dryer *0.14+ Mobile phone *0.028+ Sound system 1 ) What best describ…
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**Things you buy Carbon Emissions (tCO2): (( TV - F521033 *89.5+ Dishwasher *75 + Washing machine *100+ Laptop - F521070 *30+ Tablet - F521072 *36+ Home desktop comp… *45+ Power tools *5.9+ Hair dryer *5.9+ Mobile phone *66+ Sound system 30)/1000) What best describ…
Things waste footprint
The first of the calculation below established the waste from clothes, the second shoes, third takes off savings made using a multiplier of 10KG, and the forth includes technological items.
- Things Waste Footprint (KG): How many items of clothing do you buy every year… /( Use my clothes and shoes as long… x I buy second hand… x Buy clothes from ethical sources ) + ( How many pairs of of shoes * Buy shoes from ethical… ) + 10 - (10*( Use re-usable nappies + Use refillable coffee… + Avoid buying short term… + Use refillable or non-package items… ))+ Things you buy weight
Things carbon footprint
The first part of the calculation looks at clothes, giving a multiple of 23.2KGCO2 per KG of clothes (taken from WRAP report). The second part looks at shoes and gives a multiple of 5.725KGCO2 per KG of shoes (averaged from shoes in this life-cycle assessment). We then include leisure facilities and hotels (which are already in values of kgCO2 and then converted into tonnes. We then use a value of 1.4 KGCO2e for each 1 KG of waste to include waste factor.
- tCO2e: (( How many items of clothing… x Buy clothes from ethical sources x 23.2)/1000) +( How many pairs of shoes * Buy shoes from ethical sources x 5.725) /1000+((( On average every month … leisure facilities + How many nights at a hotel… ) x Stay in eco friendly… )/1000)+ Things you buy can buy carbon emissions… +( Things waste footprint *0.0014)
Things water footprint
We used data from the WRAP Report identify a Water use per KG of clothing, which was 7,060 litres for each KG of clothing. This then gave a fairly straightforward water calculation (which didn’t include Things you buy or shoes):
- m3 water: ( How many items of clothing… * Buy clothes from ethical… *7060)/1000
Things land use footprint
Finding data for land use was really hard. What we did was establish a land use for each item of clothing. To do this we assumed cotton was predominantly used. A report was found identifying the KG per hectare of cotton production in China, to which we used an average finding that 1434KG are produced from 1 hectare. We found a report which gave a value of 8 onces of cotton were needed to produce one teeshirt. We then got a value of 0.158 m3 of land to produce 1 teeshirt. We also thought we’d do the same for a pair of jeans with this report giving a value of 0.68KG of cotton to produce a pair of jeans, giving a value of 0.42 hectares to produce a pair of jeans.
We thought it fair considering these calculations to give a value of 0.3 m3 for an average item of clothing, and used for the following calculus to give hectares of land used:
- Hectares: ( How many items of clothing *0.3)/1000
We acknowledge that mineral extraction for things you use and shoes haven’t been included - we would love some data if anyone has any
What savings will you pledge to make or have made as a result of interacting with Better Century?
Similar calculation to above were used to identify the savings:
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Carbon footprint reductions (tCO2e): (( How many items of… *( *Buy less clothes… + *Buy clothes and … ) *23.2)/1000) +(( How many pairs of… *( *Buy less clothes… + *Buy clothes and … ) *5.725) /1000)+(( How many nights a… * *Stay in eco frie… ) /1000)+(( Things waste foot… *1.4)/1000)
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Things waste footprint reductions (KG): ( How many items of… + How many pairs of… )*( *Exchange and buy… + Buy clothes and … )+(10( *Use re-usable na… + Use refillable co… + *Avoid buying sho… + *Use refillable o… ))+( Things you buy we… * *Use the technolo… )
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Things water footprint reductions (m3): ( How many items of… 7060)( *Buy clothes and … + *Buy less clothes… + *Exchange and buy… )/1000
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Things land use footprint reductions (hectares): (( How many items of… 0.3)/1000)( *Buy less clothes… + *Buy clothes and … + *Exchange and buy… )
Please provide comment on the above by hitting reply to this post - we want to improve the calculator!