Life Cycle Analysis (also called life cycle assessment or LCA) is vital to check how sustainable a process or product is. Here, our LCA expert Dr Rukayya Ibrahim Muazu explains what it is and how it’s done.
Like many people in sustainability, Rukayya has both passion and expertise. She is dedicated to changing the world for the better and her expertise is as impressive as her work ethic. Rukayya is a chemical-environmental engineer, with a B.Eng. in Chemical Engineering from the Federal University of Technology, Minna, Nigeria. Plus she has an MSc in Process Industry Business Management from Warwick University and a PhD in Environmental Engineering and Energy Systems at UCL.
LCA is a tool that allows you to analyse a process or a product against certain outputs. An example of a product could be making something, like a cup. A process could be getting 1 litre of petroleum out of the ground.
The person doing the LCA chooses what output they want to measure. A common choice is CO2 or carbon footprint. Other examples of outputs are toxicity or contribution to global warming.
Once these decisions have been made, a lot of data is inputted into LCA software, and the results are in the form of the output you have selected. For example, for getting the petroleum out of the ground you would look at the machines used to do it, their specifications and operational data, including resources, energy used and environmental releases from the production of the machines. You would also look at the whole refinery, and work out how much of what is used, and then apply to this 1 litre.
Data is the most important part of an LCA. Different data need to be collected for a product life cycle assessment, but mainly the foreground data and the background data.
You also have to set the parameters, that is, how far back you go. Do you draw the line at the ingredients arriving at the factory? Or do you look at the life cycles of all the ingredients? Do you then look at their life cycles and so on?
Foreground data consist of direct process data for the product under consideration, including processes in its life cycle stages. Data like that is usually obtained from industry or companies involved in the product’s manufacturing and use.
Background data are related to secondary processes in the product’s life cycle, including materials, fuels and transport processes. This background data is usually obtained from standard data bases such as the Ecoinvent and literature (published papers and research).
A lot of industries want to be able to show they are sustainable. LCA is a way they can demonstrate this, it sets a standard, and can do away with a lot of misleading product claims.
LCA is generally – though not always – done for comparison. For example, a company could use an LCA to compare one product against another. Perhaps they want to measure the environmental impact of an updated version of a phone against an existing model. LCA can be used to do that.
Of course they can be misused too, people can abuse LCA. They might focus on only one parameter, though another is very damaging. Or they might not put all the data in. Or they could use a bad data set.
LCA is the most recognised tool to assess the potential environmental impacts of products or processes. One of the strengths of LCA is its ability to handle multiple substances and processes. So with our cup example, it would be all the ingredients of the cup, all the ways those ingredients were themselves created. This then gives you a single output to measure and compare to other cup making processes. This could be CO2 emissions, and then you can choose which cup makes less CO2.
Another strength is that LCA is flexible and can be done before the product is ever made. But it may only be once production starts that some aspects of the process come to light. In these cases an LCA may need to be updated along the way, and because it is flexible, it can be.
However, one weakness is that LCA does not automatically take account of toxicity and risk. It’s all well and good to have a low carbon footprint if a by-product of your cup making is a toxic substance that is being pumped out into the local environment!
For this reason, many experts believe we need to integrate Environmental Risk Assessments (ERA) – which analyse in terms of risk. An ERA is interested in all the possible problems and damage from a process.
To go back to the cup, maybe the LCA shows a low carbon footprint but then an ERA is completed. This would show that a toxic substance is being produced. Further, it would look at the risks of it getting out into the local environment, and its threat to various species.
Many people have looked at integrating these 2 tools over the past 15 years. And there have been some successes, but nothing universal. For example, UNEP/SETAC life cycle initiative has developed a model which has consensus, but is limited. Most integrations lean towards either the LCA end or the ERA end.
Part of my role for the Plastics: Redefining Single-Use project is to look at the conceptual side of LCA and ERA. Why do we need them? Why not do the LCA and then the ERA rather than try and combine the two of them?
The dataset needed to do this would be enormous, perhaps impossibly so.
Well, yes – though they might not do it very well!
There is software that allows anyone to run an LCA. But there can be problems with using software like this if you are not an expert. Because LCA can give misleading results if you don’t know what you’re doing. So I would say that it is ok for a non-expert to do an LCA, but it is best if they only use this for reference, rather than rely on it completely. Generally speaking, there is no rigour unless someone who really understands LCA does one.
So for an LCA to be properly useful, it should really be a scientist or an engineer who runs them. This is because scientists and engineers can go deeper into the LCA and really understand it. They can also make changes and optimise the thing – the product or process – being tested by the LCA and see how the outputs change. Maybe they change the ratio of a material being used, say recycled plastic to new plastic. It takes an engineer to know if, and how, those changes can be made.
Yes, but also the ERA. Risk is very important. Of course there are some things that have no risk, no negative outputs – but then how would you know until you have done an LCA or ERA?
LCA is absolutely the best way to back up environmental claims.
I want to make a positive impact, to relieve problems and help people. I think that’s why I wanted to be a doctor as a child – I want to be part of the team that helps.
However, I didn’t learn about sustainability and environmental problems until I was at university. I grew up in Nigeria, which is a developing country, and sustainability was not a primary goal. In general back then developing countries were not so aware of environmental problems.
Our primary goal in Nigeria, where I studied engineering at university, was to meet energy demand because of the energy problems facing the country. We learned little about sustainability. Later on, during my Masters, I got a chance to learn about the scale of the problems we face. Since then, I have been drawn to the sustainability cause.
As a child I wanted to be a medical doctor, to help people from a place of knowledge, but I think that was because I saw doctors, I didn’t see female engineers.
In Nigeria, as with many places in the world, there weren’t many female engineers for me to emulate. In fact, few women were educated past high school level. But there are more women in education and science in Nigeria now. Though – as is true across the world – women are still not equally well represented.
But it seems to be my destiny to be an engineer – I have been in the right place at the right time to be exposed to examples and situations that guided me into engineering.
My husband is an engineer too and he works in industry. Sometimes I envy how much practical application he gets to do! However, in industry your work stays local, in the plant or company you work for. Whereas with research, you get to contribute to knowledge. You find new things out, and you share it, put it out there for other people to use.
Research and study are for me both very satisfying and comforting. I am filled with curiosity and love learning new things. And I love working – and especially on the projects I get to contribute to, such as Plastics: Redefining Single-Use. What I really want to do is contribute to the world and strengthen myself, and this project allows me to do that.
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Interview by by Claire Moran