C14.5 - Life cycle assessments Flashcards
Life Cycle Assessment (LCA)
A life cycle assessment (LCA) is carried out to assess the environmental impact of products, processes or services at different stages in their life cycle
What are life cycle assessments used for?
Life cycle assessments are used to assess the impact on the environment caused by:
- Getting and processing the raw materials
- Making the product (and any packaging)
- Using, reusing and maintaining the product
- Disposing of a product at the end of its useful ‘life’
Life cycle assessments are used to assess the impact on the environment caused by:
1. Getting and processing the raw materials
2. Making the product (and any packaging)
3. Using, reusing and maintaining the product
4. Disposing of a product at the end of its useful ‘life’.
What is taken into account?
Life cycle assessments are used to assess the impact on the environment caused by:
1. Getting and processing the raw materials
2. Making the product (and any packaging)
3. Using, reusing and maintaining the product
4. Disposing of a product at the end of its useful ‘life’
The total energy needed to extract raw materials, make the product and distribute it, plus any other transport involved, are all taken into account
How is a life cycle assessment carried out?
A life cycle assessment is carried out by:
- Listing all the energy and material inputs and all the outputs into the environment
- Evaluating the potential environmental impacts from these inputs and outputs
- Interpreting these results to help make decisions about using 1 material, process, product or service over another
How does a life cycle assessment start?
A life cycle assessment starts with the process of gathering raw materials needed to make the product
A life cycle assessment starts with the process of gathering raw materials needed to make the product.
When does a life cycle assessment end?
A life cycle assessment ends when all the materials are returned to the environment
A life cycle assessment starts with the process of gathering raw materials needed to make the product and ends when all the materials are returned to the environment.
So, what does a life cycle assessment provide?
A life cycle assessment provides an estimate of the total environmental impact resulting from all stages in the product’s life cycle
What do the outputs back into the environment include?
The outputs back into the environment include:
- Atmospheric emissions
- Waterborne wastes
- Solid wastes
- Energy dissipation to the surroundings
- Any other products made in the process or product being assessed
The stages in a life cycle assessment
The stages in a life cycle assessment:
- Raw material extraction
- Manufacture/Packaging/Distribution
- Use/Reuse/Maintenance
- Recycle/Waste management
The outputs of raw materials, after raw materials have been inputted
The outputs of raw materials, after raw materials have been inputted, are atmospheric pollutants
The outputs of manufacture/packaging/distribution
The outputs of manufacture/packaging/distribution are waterborne wastes
The outputs of use/reuse/maintenance, after energy has been inputted
The outputs of use/reuse/maintenance, after energy has been inputted, are solid wastes
The outputs of recycle/waste management
The outputs of recycle/waste management are the coproducts
What will the results of a life cycle assessment always be?
The results of a life cycle assessment will always be open to debate
When considering the environmental impact (and health implications), what is it common to do?
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’.
What does this require?
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’
This requires selective judgements to be made, usually by the people who paid for the study, an expert panel, or the analyst who devised that particular life cycle assessment
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’.
This requires selective judgements to be made, usually by the people who paid for the study, an expert panel, or the analyst who devised that particular life cycle assessment.
What is also important?
The scale of the impacts is also important
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’.
This requires selective judgements to be made, usually by the people who paid for the study, an expert panel, or the analyst who devised that particular life cycle assessment.
The scale of the impacts is also important, but what should be applied?
The scale of the impacts is also important, but what weightings should be applied to global impacts, compared with regional impacts and local impacts?
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’.
This requires selective judgements to be made, usually by the people who paid for the study, an expert panel, or the analyst who devised that particular life cycle assessment.
The scale of the impacts is also important, but what weightings should be applied to global impacts, compared with regional impacts and local impacts?
What are these?
These are not objective scientific judgements
Examples of global impacts
Examples of global impacts are:
- Global warming
- The depletion of natural resources
Examples of regional impacts
Examples of regional impacts are:
- Acid rain
- Smog
Examples of local impacts
Examples of local impacts are:
- Water loss from ground water
- Toxic emissions into a stream
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’.
This requires selective judgements to be made, usually by the people who paid for the study, an expert panel, or the analyst who devised that particular life cycle assessment.
The scale of the impacts is also important, but what weightings should be applied to global impacts, compared with regional impacts and local impacts?
These are not objective scientific judgements.
When are such judgements also made?
Such judgements are also made when trying to quantify all the inputs and outputs listed in the life cycle assessment
When considering the environmental impact (and health implications), it is common to convert data collected into a single ‘impact score’.
This requires selective judgements to be made, usually by the people who paid for the study, an expert panel, or the analyst who devised that particular life cycle assessment.
The scale of the impacts is also important, but what weightings should be applied to global impacts, compared with regional impacts and local impacts?
These are not objective scientific judgements.
Such judgements are also made when trying to quantify all the inputs and outputs listed in the life cycle assessment.
An example
Such judgements are also made when trying to quantify all the inputs and outputs listed in the life cycle assessment
For example, when judging the impact of 5000 tonnes of sulfur dioxide gas against 2000 tonnes of nitrogen dioxide gas released into the atmosphere, the questions to be asked include:
1. What potential impact does the release of each gas have on smog and on acid rain?
2. What are the effects on asthma sufferers?
What happens when sometimes there is no hard factual data available?
Sometimes when there is no hard factual data available, estimations are made
Sometimes when there is no hard factual data available, estimations are made.
An example
Sometimes when there is no hard factual data available, estimations are made
For example, from articles in journals or from a company’s published figures
Sometimes when there is no hard factual data available, estimations are made.
What should calculations of data based on assumptions do?
Calculations of data based on assumptions should include an indication of the uncertainty (answer +/- uncertainty)
When should numerical values only be used in life cycle assessments?
Numerical values should only be used in life cycle assessments where widely accepted data is available for energy, water, resources and wastes
What will life cycle assessments highlight?
Life cycle assessments will highlight environmental impact and health issues when comparing products or processes, but do not take into account differences in the cost or performance
Life cycle assessments will highlight environmental impact and health issues when comparing products or processes, but do not take into account differences in the cost or performance.
What should the best practice do?
The best practice should incorporate a peer review process into the life cycle assessment to check the data and validity of conclusions drawn
Life cycle assessments will highlight environmental impact and health issues when comparing products or processes, but do not take into account differences in the cost or performance.
The best practice should incorporate a peer review process into the life cycle assessment to check the data and validity of conclusions drawn.
When is this especially desirable?
The best practice should incorporate a peer review process into the life cycle assessment to check the data and validity of conclusions drawn
This is especially desirable if a life cycle assessment is conducted by the company that makes the product being assessed and its results are then used to make claims in advertising
