What is an LCA? a short introduction
Life Cycle Assessment (LCA) is a framework used to evaluate the environmental impact associated with a product, process, or service throughout its entire life cycle. The term "life cycle" refers to the main stages of the product, service, or process, including the extraction of raw materials, manufacturing, transportation, use and maintenance, and disposal or recycling into a possible next life cycle.
The life cycle of a specific system typically consists of five phases:
- Extraction of raw materials
- Production
- Transportation
- Use and maintenance, and
- Waste processing
- Link of materials, components, or other aspects to the next cycle.
LCA is used to help people understand the environmental impact of a system and identify areas for improvement. It provides a standardised method for measuring environmental impact, making it easier to compare different products or services. By identifying the areas of the life cycle that have the most significant environmental impact, changes can be made to reduce the negative impact and make the system more sustainable.
An LCA typically includes a lot of competitive sensitive information about suppliers, production processes, and bill of materials. Hence, the EPD is introduced. An environmental product declaration (EPD) is a declaration of the environmental impact of a product that is drawn up based on an LCA. This declaration is always verified by a third party and only consists of the environmental impact assessment, and some general information.
History of LCA
The concept of Life Cycle Assessment (LCA) has its roots in the 1960s when concerns about the environmental impact of industrial processes began to emerge. However, it wasn't until the 1970s that LCA started to take shape as a methodology.
In 1969, Coca-Cola commissioned a study to evaluate the environmental impact of its packaging, which led to the development of the first formal LCA methodology. The methodology was refined and standardised over the following years, with the first published LCA appearing in 1976.
During the 1980s and 1990s, LCA gained popularity as an environmental management tool, particularly in Europe, where it was incorporated into government policies and regulations. In 1993, the Society of Environmental Toxicology and Chemistry (SETAC) established guidelines for LCA methodology, which further helped to standardize the approach.
In the early 2000s, LCA gained traction in other parts of the world, including North America and Asia. Today, LCA is widely recognized as a valuable tool for evaluating the environmental impact of products, processes, and services and is used by businesses, governments, and NGOs around the world to guide decision-making and promote sustainability.
Why carry out a life cycle assessment?
An LCA gives detailed insight of the environmental performance of the studied system; whether it’s a product, service, or an organisation. There are several reasons why you might carry out a LCA study. Here are some of the most common reasons:
- Sustainable strategies for businesses: you can’t manage what you can’t measure. LCA’s provide valuable insights of products, services, or your whole organisations. This facilitates effective sustainability strategies since you can divide capital to the highest environmental hotspots and easily identify low-hanging fruit.
- Product development and design: an LCA is used to inform product development and design decisions by identifying environmental hotspots and opportunities for improving the environmental performance of a product. For example, you could compare the environmental impacts of different materials, production processes, or transportation methods to determine which options are more environmentally friendly.
- Marketing and communications: an LCA provides valuable information that can be used in marketing and communications to demonstrate the environmental performance of a product or process. This is especially important if you are targeting environmentally conscious consumers or if you need to meet environmental regulations or standards. Recent studies have proven that consumers get more aware of greenwashing, well-supported information is therefore crucial.
- Procurement and public tenders: in different countries EPDs are requested for procurement and/or public tenders. EPDs are formal summaries of LCA reports and communicate the environmental impact, leaving out all other competitive sensitive information.
- Policy development: an LCA provides information that can be used to inform the development of environmental policies and regulations. For example, an LCA could be used to determine the carbon footprint of a specific industry, which could then be used to develop policies aimed at reducing greenhouse gas emissions.
- Supply chain management: An LCA can be used to assess the environmental impacts associated with a product or process across the entire supply chain, from raw material suppliers to end-of-life disposal. This can help identify opportunities for improving the environmental performance of the entire supply chain.
- Compliance with future legislation: an LCA provides information that is necessary for different reporting regulations like the CSRD, SFDR, and the ESPR on digital product passports.
- Transition finance: Private equity, and other financial services like bank loans or private debt, can use the insights of LCA for investment decisions, encouraging improvement of their asset companies, and for portfolio footprints. Read more about that in this article.
LCA: Cradle-to-gate vs cradle-to-grave
Cradle-to-gate and cradle-to-grave are two different types of Life Cycle Assessments (LCAs) that evaluate the environmental impact of a product or service over its entire life cycle.
Cradle-to-gate LCA considers the environmental impact of a product or service from the extraction of raw materials through the manufacturing process and up to the point where it leaves the factory gate or is ready for distribution. This type of LCA focuses on the production and manufacturing stage, also known as the upstream stage.
On the other hand, cradle-to-grave LCA considers the entire life cycle of a product or service from the extraction of raw materials through the manufacturing process, use phase, and disposal phase. This type of LCA considers the environmental impact of the product or service throughout its entire life cycle, including downstream stages such as use and end-of-life disposal or recycling.
The key difference between cradle-to-gate and cradle-to-grave LCA is that the former focuses only on the upstream stage, while the latter considers the full life cycle of the product or service. Both types of LCA can be useful in evaluating the environmental impact of a product or service and identifying areas for improvement.
Typically, the choice for one of both approaches depends - and is determined - in the goal and scope phase of performing an LCA study.
Option 3: LCA with a cradle-to-cradle approach
The cradle-to-cradle approach focuses on creating closed-loop systems where waste is minimised and materials are continuously reused or recycled. This is different from the traditional "cradle-to-grave" approach, where products are designed to be used once and then disposed of.
Like the cradle-to-grave approach, the cradle-to-cradle approach in an LCA considers the environmental impact of a product at every stage of its life cycle, including the energy and resources used in production, transportation, use, and disposal. In addition, the cradle-to-cradle approach focuses on improving the benefits between product life cycles. In one of the more infamous LCA impact methodologies of the EU and the Netherlands, the EN15804, these benefits are assessed in module D of the LCA. If you change the design of your product so you can facilitate product disassembly at the end-of-life, materials and/or components are much easier to reuse or recycle in the next product life cycle. This improves the sustainable performance of your product.
How does an LCA work?
The methodology of an LCA consists of four elements and is laid down in the international organisation for standardisation (ISO) 14040 and 14044. ISO 14040 series standards, Life Cycle Assessment, address quantitative assessment methods for the assessment of the environmental aspects of a product or service in its entire life cycle stages. ISO 14044 specifies the LCA requirements and provides guidelines for life cycle assessment (LCA), divided over four phases: 1) Goal and scope, 2) life cycle inventory analysis (LCI), 3) life cycle impact assessment (LCIA), and 4) interpretation.
1. Goal and scope
What is the goal of an LCA?
The purpose of an LCA is not only to collect data on the environmental impact, but also to be able to make decisions and choices based on this data. The goal of an LCA states:
- the intended application,
- the reasons for carrying out the study,
- the intended audience, i.e. to whom the results of the study are intended to be communicated, and
- whether the results are intended to be used in comparative assertions intended to be disclosed to the public.
What is the scope in an LCA?
The scope of the LCA study includes the following items:
- the product system to be studied;
- the functions of the product system or, in the case of comparative studies, the systems;
- the functional unit;
- the system boundary;
- allocation procedures;
- impact categories selected and methodology of impact assessment, and subsequent interpretation to be used;
- data requirements;
- assumptions;
- limitations;
- initial data quality requirements;
- type of critical review, if any;
- type and format of the report required for the study.
The product system and the accompanying functions of the product systems are the starting point of defining the scope in a life cycle assessment. To define the product system we identify the functional unit, determine the system boundaries, and identify the life cycle stages.
The functional unit is a quantitative description of the functional purpose or performance of a product or service. It defines the reference unit for the LCA, and is used as the basis for comparing the environmental impacts of different products or services. The functional unit can be expressed in various ways, depending on the nature of the product or service being assessed.
For example, the functional unit for a smartphone could be defined as the number of hours of operation or the number of calls made, while the functional unit for a car could be defined as the distance travelled or the number of passengers transported.
The choice of functional unit is critical, as it can significantly affect the results of the LCA. Therefore, it is important to carefully consider the functional unit and to ensure that it accurately reflects the functional performance of the product or service being assessed.
Taking the functional unit into account, we define the system boundaries of our life cycle assessment. System boundaries define the scope and extent of the study, and help to identify what processes and activities should be included or excluded from the analysis. The system boundaries for an LCA should be established at the beginning of the study and should be clearly defined and documented.
The system boundaries can be divided into two main categories: functional and geographical boundaries.
- Functional boundaries define the processes and activities that are included in the assessment. These include all the inputs and outputs of the service - or product life cycle, including raw materials extraction, manufacturing, transportation, use, and disposal. The functional boundaries also define which life cycle stages will be included in the assessment, such as cradle-to-gate, cradle-to-cradle, or full life cycle. If you include the use phase, you have to think about the supporting services in our product-service system; e.g. battery chagrin in mobile phones, or maintenance and parts replacement in the life cycle of a car.
- Geographical boundaries define the geographic location of the processes and activities included in the assessment. These boundaries determine the extent of the supply chain that will be included, as well as the environmental and social impacts associated with transportation and other activities that occur outside of the defined geographic boundaries.
It is important to establish clear and consistent system boundaries to ensure that the results of the LCA are comparable and that the study is conducted in a transparent and consistent manner.
Subsequently, we determine the allocation procedures in the life cycle assessment. Allocation is the process of dividing environmental impacts among products or services that share a common production process or input. In life cycle assessment (LCA), allocation is used when there is a need to divide the environmental impacts of a process or product system among multiple co-products or outputs.
There are several allocation procedures that can be used in an LCA study, depending on the nature of the product system and the goals of the study. These include:
- Physical allocation: This method allocates environmental impacts based on the physical properties or mass of the co-products or outputs. For example, if a process produces both meat and leather, the environmental impacts would be allocated based on the mass of each product.
- Economic allocation: This method allocates environmental impacts based on the economic value or market price of the co-products or outputs. For example, if a process produces both soybean oil and soybean meal, the environmental impacts would be allocated based on the market value of each product.
- System expansion: This method expands the system boundaries to include the environmental impacts of additional products or services that are avoided or displaced by the use of the co-products or outputs. For example, if a process produces both gasoline and ethanol, the environmental impacts would be allocated based on the avoided impacts of gasoline.
- Allocation based on the specific function: This method allocates environmental impacts based on the specific function or use of the co-products or outputs. For example, if a process produces both ethanol for fuel and ethanol for industrial uses, the environmental impacts would be allocated based on the specific use of each product.
- Hybrid allocation: This method combines two or more of the above allocation methods, depending on the nature of the product system and the goals of the study.
Overall, the choice of allocation method can significantly affect the results of an LCA study. It is important to carefully consider the allocation method and to ensure that it accurately reflects the environmental impacts of the product system. The International Organization for Standardization (ISO) provides guidance on the use of allocation in LCA studies. Also, some allocation procedures are prescribed in product category rules (PCRs) of the specific product or service that you are assessing.
Subsequently, the chapter goal and scope in your LCA report describes what impact assessment method is used, what impact categories you take into account. Finally, it must report on your assumptions, limitations, initial data requirements, type of critical review (if any), and the type and format of the report required for the study.
2. Life cycle inventory analysis (LCI)
It involves the collection and quantification of data on the inputs and outputs of the processes and activities involved in the life cycle of a product or service. The LCI provides a comprehensive inventory of the material and energy flows associated with the product or service and is used as the basis for assessing its environmental impacts.
The life cycle inventory analysis (LCI) consists of the following steps:
- Data collection: the data for each process within our system boundaries can be classified as following:
- Energy inputs, raw material inputs, ancillary inputs, and other physical inputs.
- Products, co-products, and waste
- Emissions to air, discharges to water and soil,
- Other environmental aspects.
It is important in this step to look at the availability of any EPDs of raw materials and consumables. With EPDs you use the results of previous LCA of components in your product-service system as input for a subsequent LCA. These EPDs are the highest quality data input of materials or components possible in a downstream LCA.
- Data calculation: Following the data collection, calculation procedures, including validation of data collected, the relating of data to unit processes, and the relating of data to the reference flow of the functional unit are needed.
The data collected in the LCI is converted into standardised units to ensure that it is consistent and comparable. This involves converting the data into common units, such as mass or volume, and adjusting it for quality, location, and other factors.
- Allocation of flows and releases: Few industrial processes yield a single output or are based on a linearity of raw material inputs and outputs. In fact, most industrial processes yield more than one product, and they recycle intermediate or discarded products as raw materials. In the goal and scope sectors, you have defined the allocation procedures that you deploy in this process.
The LCI results provide a detailed inventory of the product- (or service-) system and serve as the basis for impact assessment in the LCA.
3. Life cycle impact assessment (LCIA)
The LCIA phase of an LCA is where the environmental impacts of a product or process are evaluated. In this phase, the data collected in the previous phase of the LCI, are used to assess the potential environmental impacts associated with the entire life cycle of the product or process being evaluated.
During the LCIA phase, the impacts are usually quantified and characterised by using a set of impact categories, such as global warming potential, acidification, eutrophication, ozone depletion, the impact on human health and water bodies and so on. The impacts can be expressed in various units, such as CO2 equivalent, kg of sulphur dioxide equivalent, disability adjusted life-years, and so on. Read more about different impact categories in this article.
The LCIA phase involves the use of various models and tools to help evaluate the impacts. These models and tools may include life cycle impact assessment methods, software, and databases. The most commonly used method for LCIA is the ReCiPe method, but there are also other methods such as Eco-Indicator 99, CML 2001, and IMPACT 2002+. Recently, the EU introduced the product environmental footprint method (PEF), which will play a big role in future legislations on transparency and reporting. In the Netherlands, the ‘NMD-bepalingsmethode’ assesses environmental impact in euros for the construction market.
Common software applications for LCA modelling are SimaPro, Ecochain Mobius or Helix, or OneClickLCA. The most famous databases are Ecoinvent and GaBi databases.
4. Interpretation
The interpretation phase of an LCA study is where the results from the inventory analysis and impact assessment are combined to identify environmental hotspots, draw conclusions, identify limitations, and make recommendations. The interpretation should be consistent with the goals and scope of the study and should take into account that the results are relative and do not predict actual impacts or risks.
The main purpose of the interpretation phase is to provide decision-makers with clear and understandable conclusions and recommendations based on the LCA results. It should also ensure that the presentation of the results is complete and consistent with the study's goals and scope. Hedgehog Company always clearly communicates environmental hotspots and recommendations at the end of an LCA study in the delivery meeting.
During the interpretation phase, it may be necessary to review and revise the scope of the LCA or the quality of the data collected to ensure that the results are accurate and consistent with the study's goals.
Interpretation of the results is done via ISO14040:2006, which prescribes:
- Identifying key issues based on the LCI and LCIA phase.
- An evaluation of the research itself: consistent, careful and complete?
- Conclusions, recommendations, and limitations.
The interpretation of the results ultimately leads to action. Because the hotspots of the system have become transparent, it is now possible to start working on making it more sustainable. This can be done in various forms, such as product development, strategy development or a marketing plan.
The difference between an attributional LCA and a consequential LCA?
Consequential LCA and attributional LCA are two distinct methods used in conducting life cycle assessments (LCAs) of products and processes. The main difference between these approaches lies in their treatment of system boundaries and the environmental impacts of the product or process under evaluation.
Attributional LCA traces the material and energy flows through the entire life cycle of a product or process to model its environmental impact. This method assumes that the production and use of the product or process are predetermined, and allocates the environmental impact to each stage according to pre-determined rules. In other words, attributional LCA assumes that the impact of a product is determined by the production and consumption patterns that exist in the present.
Consequential LCA, on the other hand, models the environmental impacts of a product or process by considering the changes in production and consumption patterns that would occur if the product or process were replaced by an alternative. This approach considers the potential changes in behaviour and production systems resulting from the introduction of a new product or process and models the environmental impacts of those changes. Consequential LCA assumes that the impact of a product is determined by the choices made by consumers and producers in response to the introduction of a new product or process.
In summary, attributional LCA and consequential LCA are two different approaches to conducting LCAs that differ in their treatment of system boundaries and their approach to modelling the environmental impact of products or processes. Consequential LCA is a powerful tool for identifying opportunities to improve the sustainability of products and processes and optimising resource use, while attributional LCA provides a useful baseline for comparison and evaluation of the environmental impact of existing products and processes.
Life cycle assessment examples
Over the past few years several LCA experts of Hedgehog Company have performed test LCA cases to improve their skills, out of curiosity and just for fun. You can find a list of these LCA examples below. In the first case, also an example LCA report is provided. Enjoy!
- LCA example paper books versus the e-reader. What would be better for the environment: reading a paper book or reading books on an e-reader? Read this example of a life cycle assessment comparison. Also find a example LCA report in this article.
- Alternatives to meat: a life cycle assessment. When it comes to the environment, more and more people are aware of their current dietary habits. Some are even willing to switch to a more sustainable meal. One of the first steps is to replace meat with meat substitutes. But which meat substitute has the least impact on the environment? And how do they compare to actual meat?
- Food containers: glass or plastic? Found yourself staring at a pile of mismatching containers and lids in your bottom kitchen drawer? Now, you are on your way to the store to get a new set. One of the criteria for choosing a new container is its impact on the environment: for example, whether it can be recycled or how sustainable the materials are. This article helps you answer these questions.
- How to sustainably BBQ: LCA example of different BBQs. We use a life cycle assessment (LCA) to compare different forms of BBQs. Doing so we investigate the environmental impact of this summer hobby.
- Breakfast of champions: an LCA example of the English versus the continental breakfast. What is the environmental impact of your breakfast? We performed an LCA study comparing the English and continental breakfast.
- Example LCA: which egg do you pick?. For the conscious consumer, supermarkets present lots of difficult choices. Do you opt for products packed in plastic packaging and go with paper packaging? What about a biological product or a product with a certain certification?
