LESSON 2 LIFE CYCLE ASSESSMENT Within this lesson

LESSON 2 LIFE CYCLE ASSESSMENT Within this lesson you will cover: • Understand in more detail using case studies what a life cycle assessment is and how/why they are carried out. • Understand how a life cycle assessment can be misused. • Demonstrate understanding by carrying out product evaluations using LCAs on different products using provided data.

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Starter: Strawberry Yoghurt On a post-it note, write as many materials/ingredients you can think of that go into making this product – Where does each come from? e. g. Where does the plastic for the container come from? rry e b w a Str urt h g o Y c lid i t s a l • P …. … … • ……

LIFE CYCLE ASSESMENT LESSON Lesson Success Criteria You will be able to: § State the stages of an LCA in the correct order § Carry out an LCA for plastic/paper bags with support rd 3 Complete all of silver &: § Explain the limits of LCAs § Evaluate products in detail using LCAs st 1 Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Complete all of bronze &: § Explain the importance of LCA & how it can be misused § Carry out LCAs for different products when data is supplied nd 2

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. An LCA works out the environmental impact of each of these stages of a product’s life: Extract & process raw materials Manufacturing and packaging Use & reuse Dispose Video: LCA of strawberry yoghurt. Including transport & distribution at each stage https: //www. youtube. com/watch? v=c. YOC 8_j. Jc. II

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Plastic or paper? Hands up – Plastic Hands down Paper Class Vote: Which bag has a greater environmental impact (over the course of its life)?

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Task: Comparing LCAs of plastic/paper bags § In pairs, you will complete an LCA – one person for a plastic bag, the other for a paper bag. § Find the info sheets around the room. Each sheet has info on one stage of the product’s life cycle. There are 5 sheets for each type of bag. § Copy up your partner’s notes so you have a complete table. § Give each stage a score (1 -10) for environmental impact. § 10 = most serious impact. § Calculate the total score for each § Summarise the key type of bag. information in your table.

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Comparing LCAs of plastic/paper bags LCA Stage Plastic bag Description Paper bag Score (1 -10) Description Extraction and processing of raw materials Manufacturing and packaging Use and reuse Disposal Total: Transport and distribution at all stages Score (1 -10)

LIFE CYCLE ASSESMENT LESSON LCA Stage Plastic bag Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Paper bag So plastic bags have a lower environmental Description Score Description impact. Score (1 -10) Crude oil – finite Timber – renewable but a lot of wood is Extraction and Even though plastic bags aren’t biodegradable, they take 4 8 required Fractional distillation, cracking processing of Pulping, and processing less energy to make than paper bags – this is because so Lots of energy, little waste raw materials Lots of energy, lots of unusable waste much energy is used to pulp the amount of timber needed. Processed, then cut Manufacturing and packaging 5 Each stage uses energy Note! 5 Each stage uses energy Packaged in cardboard Total: 28 Even though crude oil extraction and processing uses a lot Total: 23 No impact of use Only used once – so more needed Use and reuse 3 6 of energy, there is little waste unlike paper production, and Strong so reusable a lot of wood is needed to make paper bags strong Disposal Recyclable – requires energy Not biodegradable 6 Recyclable – requires energy 4 Biodegradable Take up space in landfill No pollution Finally: plastic bags have a longer lifespan as they can be Transport: Transport and reused. 5 5 Rig to plant to manufacturer to shops Forest to plant to manufacturer to shops distribution at all stages https: //www. youtube. com/watch? v=d 7 F 0 DWjzq 0 U Total:

LIFE CYCLE ASSESMENT LESSON Problems with LCAs Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. allocate a numerical value to • Unlike in this task, in the real world it is easy to quantify: – Use of water – Use of resources – Amount of energy used – How much waste is produced • But it is not easy to quantify the effects of pollutants. Why? We can’t be sure what the overall total effect will be. • This means we have to use value judgements The scores you came up with in the task. • What is the problem with using value judgements?

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Problems with LCAs Value judgements are subjective. Objective = fact Subjective = opinion Because LCAs use a mix of numerical values and value judgements, LCAs are not a purely objective process.

LIFE CYCLE ASSESMENT LESSON Objective - Learner will gain knowledge & understanding of life cycle assessments using provided data. Plenary • What’s the difference between carbon footprint and LCA? • The carbon footprint is the total amount of CO 2 and other greenhouse gases emitted over the full life cycle of a product, service or event • An LCA analyses the total environmental impact – i. e. not just greenhouse gases but also water use, non-gaseous pollutants, amount of waste Extract & process raw materials Manufacturing and packaging Use & reuse Dispose