Hotspot Analysis in LCA: How to Identify Them
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Most sustainability teams run a full LCA and then stop. They get a total carbon number, file it in a report, and move on. But the real value of a life cycle assessment is not the headline figure, it is knowing where the impact comes from and, crucially, what you can do about it. That is exactly what hotspot analysis in LCA is designed to answer. In a car tire, for instance, 65% of the carbon footprint lies upstream in raw materials, not in the energy-intensive vulcanisation process most manufacturers assume is the problem. This guide explains how to identify hotspots in an LCA, why the results are so often counterintuitive, and how to translate those findings into decisions your product and sourcing teams can actually act on. If you are new to the broader methodology, Life Cycle Assessment: The Complete Guide (2026) is a good starting point before diving in here.
Key Takeaways
- Hotspot analysis involves systematically evaluating the contribution of different unit processes, life cycle stages, or individual flows to the total environmental impacts of a product system.
- The stage generating the most emissions is rarely the most obvious one. Raw materials, use phase, and end-of-life each dominate in different product categories, sometimes in unexpected order.
- A widely used practical threshold, proposed within the EU Product Environmental Footprint framework, is that life cycle stages, processes, or elementary flows that together make up 80% of the cumulative impact to any relevant impact category should be considered significant.
- Hotspot analysis should consider both the magnitude of impacts and the feasibility of intervention, because the most significant contributor to impacts may not always be the best opportunity for improvement if technical or economic constraints limit potential changes.
- Identifying hotspots early, even through a screening LCA, saves resources and focuses ecodesign, procurement, and supplier engagement where they will have the greatest leverage.
What Is a Hotspot in LCA?
A hotspot is a stage, process, activity, or specific aspect within a product system that contributes disproportionately to one or more environmental impact categories relative to other components of the system. The classic example is stark: a process contributing 60% of the total climate change impact while representing only 5% of the economic value would clearly be identified as a hotspot.
This analysis typically follows the Life Cycle Impact Assessment phase, where characterised impacts are examined to determine which elements of the system are responsible for the largest shares of environmental burden. In practice, this means you are not just looking at a single number. You are decomposing the total result by life cycle stage (raw materials, manufacturing, use, end-of-life), then by individual process, and sometimes down to the level of individual elementary flows such as a specific energy carrier or a single chemical input.
When applied to Life Cycle Assessment, the benefits of hotspots analysis include ensuring focus on priority issues such as waste, water, and materials of concern, as well as focus on the right life cycle stage, from material acquisition through manufacturing, use, and end of life. That focus is what makes the technique so valuable for product teams who need to prioritise action, not just account for emissions.
Why Hotspot Analysis Defies Intuition
Here is the challenge: most people assume the biggest impact happens where they can see it. A manufacturer looks at their factory floor and assumes production is the problem. A logistics manager sees trucks leaving the warehouse and assumes transport dominates. Hotspot analysis in LCA routinely upends these assumptions.
Consider a car tire. Many people would guess that the rubber vulcanisation process, a high-temperature, energy-intensive step, is the main emissions driver. According to Devera’s benchmark for a car tire, the median carbon footprint is 41.41 kg CO₂e, but manufacturing accounts for only 27.8% of that. Raw materials, primarily the rubber compounds and carbon black inputs, drive 65.0% of the total. If a tire manufacturer focused their sustainability programme on factory energy efficiency alone, they would be targeting a lever that controls less than a third of their product footprint, while the real hotspot sits upstream in their supply chain.
Now contrast that with a laptop. Devera’s laptop benchmark places the median footprint at 215.10 kg CO₂e, with the impact split fairly evenly across three phases: use phase (38.3%), raw materials (36.5%), and manufacturing (24.7%). Here, no single stage dominates, which means a laptop brand faces a fundamentally different strategic challenge than a tire manufacturer. Reducing the use-phase footprint requires influencing consumers (software efficiency, longevity, renewable energy at home). Reducing the raw materials share requires supply chain intervention. Both are genuine hotspots, and missing either one produces an incomplete reduction strategy. This is explored in more depth in our post on Consumer Electronics Sustainability: LCA, Data & 2026 Compliance.
The contrast between these two products illustrates a core principle: the location of hotspots is product-specific. No assumption holds across categories. You have to do the analysis.
The Four Steps to Identifying Hotspots in an LCA
Step 1: Complete the Inventory and Impact Assessment
Hotspot identification sits within the Interpretation phase of the ISO 14040/44 framework, but it depends entirely on the quality of what comes before it. Performing a hotspot analysis in LCA involves completing the inventory and impact assessment phases to quantify emissions or other impacts across the product’s life cycle. You cannot reliably rank contributors if the underlying inventory is incomplete or relies on poor-quality secondary data.
Contribution analysis, as defined by ISO 14044, is a step of the Interpretation phase to assess the contributions from entities like individual life cycle stages, groups of processes, elementary flows, and indicator results to the overall LCI or LCIA result, expressed as a percentage. This is the formal mechanism through which hotspots are surfaced.
Step 2: Rank Contributions by Stage and Process
Once characterised impact results are available, you rank life cycle stages from highest to lowest contribution across the impact categories you are investigating. A commonly applied threshold is that a process or stage contributing a minimum of 10% of total impacts qualifies as a hotspot for further attention. The EU Product Environmental Footprint approach tightens this further: with PEF, a hotspot can be identified at different levels of granularity, impact category, life cycle stage, process, or elementary flow, and a clear threshold is proposed whereby the stages or flows that together make up 80% of the cumulative impact to any most relevant impact category should be considered relevant.
Hotspot analysis can be used to analyse the most relevant drivers of LCA impacts, and it can be repeated for each impact category, is embedded in commercial LCA software, and can be done at life cycle stage, process, technological, and elementary flow levels. Starting at the stage level and progressively drilling down keeps the work manageable.
Step 3: Apply Sensitivity and Uncertainty Checks
A percentage contribution figure alone is not enough. A good hotspot analysis is also about understanding the individual emissions and resource uses behind the scores, their level of uncertainty, and the level of control the company has over those emissions and resource uses.
This matters enormously in practice. A raw materials stage that accounts for 60% of the footprint but relies on a single secondary emission factor with high uncertainty deserves careful treatment. Sensitivity analysis, varying that emission factor within its reported range and observing how the ranking changes, tests whether the hotspot identification is robust. If the raw materials stage holds its top rank even under conservative assumptions, the hotspot is confirmed. If the ranking flips under different data scenarios, further primary data collection is warranted before any major investment decision is made.
Step 4: Assess Actionability
Hotspot analysis applied to LCA focuses not only on the right life cycle stage but also on the right actors, producers, manufacturers, suppliers, retailers, customers, and government officials, to evaluate, influence, and implement solutions. This is where the analysis moves from being a measurement exercise to a strategic one.
A hotspot in the raw materials stage of a product you manufacture in-house is very different from a hotspot in a raw material sourced from a single-supplier commodity market. You may have direct leverage in the first case and almost none in the second. Mapping hotspots against your degree of control produces a prioritisation matrix that is genuinely useful for sustainability roadmapping.
A Counterintuitive Example: The T-Shirt vs the Laptop
One pattern that surprises most product teams is how differently hotspots distribute between a simple textile and a complex electronic device. A cotton T-shirt shows manufacturing dominating at 60.1% of a median 3.01 kg CO₂e footprint, with raw materials contributing 23.5%. So for a garment brand, the dyeing and wet processing facilities used by their tier-1 suppliers are the primary hotspot, not the cotton fields.
A laptop, by contrast, distributes its 215.10 kg CO₂e nearly equally across three phases. Any brand that wants to move from, say, a C-grade footprint (above 228.4 kg CO₂e) to a B-grade (below 203.0 kg CO₂e) cannot get there by fixing just one phase. They need parallel interventions: cleaner electricity at the point of use, lower-carbon component sourcing, and more efficient manufacturing.
| Product | Raw materials | Manufacturing | Use phase | Total footprint |
|---|---|---|---|---|
| Car tire | 65.0% | 27.8% | 0.0% | 41.41 kg CO₂e |
| Laptop | 36.5% | 24.7% | 38.3% | 215.10 kg CO₂e |
| Cotton T-shirt | 23.5% | 60.1% | 11.3% | 3.01 kg CO₂e |
This multi-hotspot reality is exactly why contribution analysis must precede any reduction roadmap, not follow it.
Common Mistakes in LCA Hotspot Identification
Stopping at the stage level. Life cycle stages are useful for a first pass, but real reduction opportunities live at the process and flow level. Knowing that “raw materials” is the hotspot for a car tire tells you to look at the supply chain. Knowing that carbon black from furnace-process production is the dominant elementary flow tells you what to actually negotiate with your supplier.
Ignoring impact categories beyond climate change. GHG emissions are the most frequently reported metric, but hotspots for water stress, land use, or particulate matter can sit in entirely different places within the same product system. A single-impact-category focus can produce a reduction strategy that shifts burden rather than eliminates it.
Confusing magnitude with controllability. The most significant contributor to impacts may not always be the best opportunity for improvement if technical or economic constraints limit potential changes. Screening hotspots through a lens of feasibility prevents sustainability teams from spending two years trying to decarbonise a commodity they have no power to change.
Using low-resolution data for high-stakes decisions. Beginning with a simplified screening LCA to identify major environmental hotspots before investing in a full-scale analysis is good advice, but the screening results should inform where to invest in primary data, not serve as the final basis for public claims or supplier negotiations.
From Hotspot Identification to Action
Once hotspots are confirmed and ranked by both magnitude and feasibility, the output feeds directly into three types of decision-making.
Product design changes. If raw materials dominate (as in the car tire example, at 65.0%), the ecodesign response is to explore lower-carbon material substitutes, recycled feedstocks, or material reduction. Design for Environment Principles: A Practical Guide covers how to embed this thinking at the earliest stages of product development.
Supplier engagement. A confirmed upstream hotspot creates a data-backed brief for supplier conversations. Rather than asking a supplier to “be more sustainable,” you arrive with specific numbers: the emission factor for their process, its contribution to your product footprint, and the gap between their current performance and best available technology.
Public claims and reporting. Under frameworks like the EU Green Claims Directive and CSRD, substantiated environmental claims need to be backed by methodologically sound LCA data. Hotspot analysis is the mechanism that connects your full LCA to specific, defensible reduction statements. Claiming a 20% reduction in product carbon footprint is credible only when you can show which hotspot you targeted, what intervention you made, and how the recalculated footprint was verified.
Frequently Asked Questions
What is hotspot analysis in LCA and how does it differ from a full LCA? A full LCA quantifies environmental impacts across all stages of a product’s life cycle, following the ISO 14040/44 framework. Hotspot analysis is the interpretation step within that process that ranks which stages, processes, or material flows contribute most to those impacts. It is essentially the “so what” layer on top of the quantitative results, and it is what turns a carbon number into an actionable reduction strategy.
How do you identify the threshold for a hotspot in a product LCA? Practice varies, but two benchmarks are widely used. A process or stage contributing more than 10% of total impacts is generally flagged for further investigation. The EU Product Environmental Footprint framework goes further, treating any set of stages or flows that cumulatively account for 80% of the total weighted impact across the most relevant impact categories as the definitive set of hotspots requiring attention.
Why does hotspot analysis sometimes point to life cycle stages the company does not control? Because environmental impact follows physical flows, not organisational boundaries. Raw material extraction and end-of-life treatment can easily dominate a product’s footprint even though the manufacturer has no direct operational control over either. This is why hotspot identification must be paired with a feasibility assessment, mapping each confirmed hotspot against what lever the company actually holds: product reformulation, supplier specification, extended producer responsibility schemes, or consumer-facing guidance.
Can hotspot analysis be done before a complete LCA is finished? Yes. A screening or streamlined LCA is specifically designed to surface likely hotspots quickly, using secondary data and simplified system boundaries. The results are less precise but can guide where to invest resources in a full study. Many teams run a screening first to confirm whether the use phase, raw materials, or manufacturing is likely to dominate, then prioritise primary data collection in those areas before completing the full ISO 14040/44-compliant assessment.
For sustainability teams who need defensible numbers rather than directional guesses, finding the hotspot is only half the work. The other half is having an audited methodology behind the numbers when regulators, retailers, or customers ask for proof. Devera calculates product carbon footprints following ISO 14040/44, with phase-level breakdowns built in so hotspot identification is part of every report, not an afterthought. Explore the platform or see pricing for your portfolio size to understand what coverage looks like at scale.