METHODOLOGY AND SOURCES

For the calculation methodology of the ecological calculator we trusted denkstatt Bulgaria

The calculator automatically calculates the environmental savings from the clothes and/or shoes left in the specialized containers based on their input characteristics.

Environmental savings consider the assumed reuse and/or recycling of textiles and shoes. This saves the resources needed to produce new textiles (in the case of re-use) or the inputs needed to produce textiles with different uses (in the case of recycling). The calculator also reflects the greenhouse gas emissions saved (carbon dioxide equivalent) from textiles ending up in landfills and their decomposition.

The quantitative and qualitative characteristics of the provided textile products determine the environmental savings values. They are derived from calculations of several parameters:

• Emission factors and ecological footprints, which take into account the quantities (weights) and materials of the textile products. These factors and footprints reflect the production of textile products – from the extraction of materials through their use in natural or synthetic fabrics, to the inputs in the actual production of the final products. The emission factor is a measure of the quantities of pollutants (greenhouse gas emissions) emitted as a result of a specific activity/production. The ecological footprint specifically considers the resources invested in the production of end products (such as invested materials, water usage, agricultural land usage for raw material extraction, etc.).
• The savings coefficient and replacement coefficient consider the possible combination of material and condition. These coefficients reflect, on one hand, the condition (durability) of the textile and its potential redirection for reuse and/or recycling. On the other hand, they address the reduction in the production of new clothes/textiles resulting from redirecting unwanted textiles for reuse and/or recycling. For example, predominantly natural fibers in good condition have a high coefficient for redirection towards reuse, which is the most environmentally friendly way to extend the life of the textile. For worn-out synthetic clothes is almost entirely energy recovery, with a very low percentage of recycling. The coefficients are based on specific data from TexCycle’s operations and the company’s specific process distribution.

The calculator automatically calculates the ecological savings from the textile products left in the containers by the user, based on several key input characteristics:

• Quantity and weight – based on the specified quantities, types of clothing and their average sizes and weights.
• Condition – based on the user’s assessment, which determines how suitable the clothing is for reuse.
• Material – based on the synthetic and/or natural composition of the textile product.

The calculator automatically calculates the ecological savings from the shoes left in the containers by the user, based on several key input characteristics:

• Quantity and weight – based on the specified pairs of shoes, their category, style (height), type (men’s, women’s, children’s), and sole (thickness and density).
• Condition – based on the user’s assessment, which determines how suitable the shoe is for reuse.
• Material – based on the synthetic and/or natural composition of the upper and sole of the shoe.

Each shoe category is associated with a specific weight, which is multiplied by two (for a pair) and the number of pairs entered by the user. Each subsequent choice of style, type of shoe and other factors changes the weight of the chosen shoe category. The ratio of the upper part of the shoe to the sole (% sole) also changes according to the user’s subsequent choices, including the density of the selected materials. This follows the logic that bigger shoes (e.g. men’s) have more weight, taller shoes (e.g. boots) have a higher proportion (weight) of their upper part, and shoes with thicker soles (e.g. synthetic rubber or platform shoes) have a heavier bottom part.

Clothing, home textiles and toys

• Clothing category, weight, condition categories, proportion of reuse, recycling or energy recovery – Internal data, TexCycle
• Replacement rate for textile products – Based on information provided by TexCycle and Bulgarian Association Circular Textile (BACT) and according to:
  – Environmental improvement potential of textiles (IMPRO Textiles), 01.2014
  – Environmental impact of textile reuse and recycling – A review
• Emission factors – CO2
  – Environmental improvement potential of textiles (IMPRO Textiles), 01.2014
  – Environmental impact of textile reuse and recycling – A review
• Water for irrigation
  – WWF Report: Cleaner and greener cotton, footprints and better practices.
  – Land: Food, Feed, Fibre. Summary facts – UN Library, Convention to Combat Desertification
• Water for production and dyeing
  – New methods for textile dyeing
  – Hazardous substances in textiles: Nijkamp, M. M., Maslankiewics, L., Delmaar, J.E., & Muller, J. J. A. (2015). Hazardous substances in textile products.
  – Composition of textile dyeing process effluents: a critical review.
  Yaseen, D.A., & Scholz, M. (2019). Textile dye wastewater characteristics and constituents of synthetic effluents: a critical review. International journal of environmental science and technology, 16(2), 1193-1226.
• Arable land
  – Land: Food, Feed, Fibre. Summary facts – United Nations Library, Convention to Combat Desertification.
  – Cotton and wool – a global view
• Chemicals
  – Environmental Justice Foundation report: The deadly chemicals in cotton ISBN 1-904523-10-2;
  – Hazardous substances in textile products: Nijkamp, M. M., Maslankiewics, L., Delmaar, J.E., & Muller, J. J.. A. (2015). Hazardous substances in textile products.
• Plastics
  – Direct comparison of 1 kg polyester for clothing equivalent to 1 kg PET.

Shoes

• Shoes characteristics (including categories, upper and sole types, material types), weight by category – Internal data, online survey, measurements and technical study.
• Reuse ratio – Based on information provided by TexCycle and Bulgarian Association Circular Textile (BACT)
• Substitution rate
  Based on information from BACT and according to:
  – Environmental improvement potential of textiles (IMPRO Textiles), 01.2014
  – Environmental impact of textile reuse and recycling – A review
• Emission factors – CO2
  – MIT Open Access Articles: Manufacturing-focused emissions reductions in footwear production
  – Waste Management & Quality Assessment of Footwear Manufacturing Industry in Bangladesh: An Innovative Approach
  – Water, energy and carbon footprints of a pair of leather shoes, ITM School of Industrial Engineering and Management, Stockholm
  – Ecoinvent database 3.8 (water footprint), 3.9.1 CO2 footprint
• Water footprint
  – Water, energy and carbon footprints of a pair of leather shoes, ITM School of Industrial Engineering and Management, Stockholm
  – Ecoinvent database 3.8 (water footprint), 3.9.1 CO2 footprint
  – Industrial Water Usage
• Plastic
  – Direct relationship shoe weight = plastic weight (excluding materials: leather/natural rubber)