LCA explained
What to choose and how to build
The dataset of the LCA is updated on January 3, 2012. If you made your LCA before that date the old data is still in your LCA. Since naming of the data in both sets is not identical you need to re-enter your materials/processes etc if you want to make use of the new set. New entries make use of the dataset ecocost 2007 on products and services v2-2, 2010. There are other, also newer, datasets available on http://www.ecocostsvalue.com
Making a LCA starts by defining your boundaries, what is included and what not. Make it to wide and you drown, make it to narrow and you will miss improvement options since those can be the largest in integration of functions and or products with services.
LCA’s are done from Cradle to Gate (think end of a process)
Step 1 The goal of your analysis
- benchmark a product or compare two or more products?
- improve the environmental characteristics of a design? Replace materials, reduce weight, less transportation or other transportation mode, take-back systems, cradle to Cradle
- Pick your measurement. What is important to you(r company)? CO2 emissions, ecocost, water intake, toxicity, acidification? What will be a better solution for one will not necessary be an improvement in an other measurement.
Step 2 “Functional Unit” and Boundary Limits
- describe the function (system requirements) of your product or service
for instance a car; 10 years life, 12000km/year on petrol, 4 new tyres per 2 years
- establish the boundary limits. What do you include and what do you neglect in your system?
Step 3 Quantify materials, use of energy, etc. in your system
- Make and inventory of the components, the materials, the weight and processes used. Either from the Bill of Material or a disassembly of a product, real life is often different from the original plan. What is the consumption (energy consumption per mode, fuel, materials)
Step 4 Enter the data in the LCA tool
- Most entries are in kg. If you select from the dock the unit is mentioned in the name.
- if a material or process is not mentioned select an alternative. For instance plastics are all within a narrow range. Casting from steel is not much different from bronze. Or ask an expert in Simapro or Gabi to calculate the material or process.
- Before you define consumption you should define the usage otherwise it will not be calculated. The tricky thing is in electricity. You fill wattage in at Usage and then select your electricity in consumption. The unit here is time, depending on how you defined usage you need to fill in here a number. Fo instance a electric bulb of 60Watt; Fill in Usage patern in Usage and 60W in Electricity then on Consumption you fill in just ‘1’ for one lamp, or ‘2’ for two etcetra.
- Transportation uses the total kg in materials. You can adjust the material weight if necessary by adding or abstracting weight under the material tab
Step 5 Interpret the results and draw your conclusions
Step 6 You can then Clone your product and change out materials, weights or or re-design ideas you have and repeat the step 3-5.
