Water Footprint as an Environmental Tool. Helena Wessman VTT Technical Research Centre of Finland

Transcription

1 Water Footprint as an Environmental Tool Helena Wessman VTT Technical Research Centre of Finland

2 08/10/ Why water footprint? Water will be the next major global issue: concern of the water resources and water quality and needs to guide the development of water-saving products Led by environmental NGOs and academics but also the industry is strongly involved Key industries: food, chemical, textile and forest industry In the Northern countries water shortage is not common and water footprint may seem irrelevant. Good water resources, low water use in the process and high water purification technologies bring benefits to the product manufacturers

3 08/10/ What is water footprint? Water footprint calculation method has been developed by researchers at the University of Twente in the Netherlands /Hoekstra 2008/ Water Footprint manual (state of the art 2009) Life-cycle thinking: WF of a product is the total volume of fresh water used directly or indirectly to produce the product. Water consumption and pollution in all steps are included.

4 08/10/ WATER FOOTPRINT Biomass raw material (eg wood) Blue water: technical water needed in process (surface and groundwater ), water content of raw material, output water from the process Green water: rainwater, water in nature Grey water: pollutants in water Green water use Product Other raw materials Blue water use Grey water Blue water use Grey water Timeframe: a year/growth season Site-specific Functional unit: volume water per mass, money, piece.. Helena Wessman

5 08/10/ Water footprint is a local indicator Information needed: to know regional water scarcity, threshold levels, dilution conditions, definition of different water types etc. Green water calculation uncertain (country/area/season specific). Definitions of water consumption and evaporation in the forest or fields, effect of land use change etc. are still unclear Blue water needs specifications as well (definitions for cooling water, evaporated water, allocation rules, compensation) Grey water expresses water quality (COD, BOD, nutrients, heavy metals, toxicity, heat). Also defined as volume of freshwater needed to dilute pollutants to acceptable level (water quality standards)

6 08/10/ ISO Water footprint: Requirements and guidelines (ISO/TC207/SC5/WG8) The standard will be in accordance with the ISO and compatible with LCA standard Timetable: Working group started in November 2009, the first WD discussed in ISO meeting July Aim to start stardardization in spring 2011 Standard development is not based on any of the existing methods directly

7 08/10/ Water footprints of some products (by University of Twente, 1 kg wheat 1000 litres 1 kg rice 3000 litres 1kg milk 1000 litres 1 kg cheese 5000 litres 1 kg beef 5000 litres WF of a crop = water use (m3/ha) / crop yield (ton/ha) in a growth season WF of an animal = sum of water used for feed, drinking and production 1 slice of bread 40 litres 1 egg 135 litres 1 cup of coffee 140 liters 1 hamburger 2400 litres 1 cotton shirt 2500 litres role Figures express global averages Green water plays the major

8 08/10/ It is estimated that water footprint of one A4-sheet Paper (80g/m 2 ) is 10 liters of water Source:

9 08/10/ Water footprint of bioenergy (Gerbens-Leevens et al, University of Twente, 2008) Replacing fossil energy with bioenergy has generated needs to estimate more detailed data about the water requirements WF of bioenergy (energy from biomass) is estimated to be 70 to 400 times bigger than WF of other primary energy carriers like hard coal or heavy fuel oil Green water plays again the leading role when biomass is in question : calculation model CROPWAT (FAO decision support system) to estimate evapo-transpiration of crops

10 08/10/ FINNISH EXAMPLES Background information, tools: (by Kemira) (HUT et al) Finnish water footprint app l/person/day, 54% is used in the households Water footprint for products: Onnelliset Luomutomaatit: water footprint is 28 l/ kg product Raisio Elovena: total water consumption 101 l/ 100 g product Helena Wessman

11 08/10/ CHALLENGES FOR THE INDUSTRY AND FOR ENVIRONMENTAL COMMUNICATION Green water definitions for region/country level Does the Grey water tell about the quality? Guidelines needed for overall data collection, data for the value chains What is the connection between land use and water footprint Water footprint is a regional indicator but regional data is missing Industry /country specific Water Footprints Helena Wessman

12 08/10/ THANK YOU FOR YOUR INTEREST! VTT Sustainability Assessment Team assessment