In our previous post, we talked about how Life Cycle Assessment (LCA) must be understood as a way to measure the real environmental footprint of something from start to finish.
But how does it actually work in practice? How do researchers go from everyday activities like “charging a drone” or “spraying a field” to a full picture of environmental impacts such as carbon emissions, water use, or resource depletion?
That’s where the four stages of LCA come in, to provide a structured, step-by-step process that helps turn complex systems into clear, measurable information.
Let’s take a look at each of the 4 stages:
- Goal and Scope Definition – Setting the Stage
- Goal and Scope Definition - Setting the Stage
Every good story starts with knowing what it’s about.
In this first step, we define:
- Why we’re doing the LCA (the goal),
- What we’re comparing (the product or service), and
- How far we’ll look along its life cycle (the scope).
This includes defining what’s called the “functional unit” , that is, a common reference point that makes comparisons fair.
For example, in the ICAERUS project, we might compare:
“1 hectare of crops monitored by drone” vs. “1 hectare of crops monitored using conventional ground methods.”
The goal is to make sure we’re comparing apples to apples (or in our case, drones to people or conventional machinery).
We also set here the system boundaries by deciding which processes to include and which to exclude:
Do we stop at the drone’s use phase, or also count the materials used to build it, its batteries, and what happens at the end of its life?
The answer depends on the study’s purpose and the available data.
2. Life Cycle Inventory (LCI) - Gathering the Data
Here’s where things get detective-like.
In this stage, we collect all the data describing what goes in and out of the system, which in the LCA jargon are called inputs and outputs.
For example:
- How much electricity does the drone use per hour?
- How much material is used to make its frame?
- How much pesticide or fuel is saved thanks to it?
- And what kind of waste or emissions result from these activities?
It’s like creating a detailed “shopping list” of all the resources and emissions that make the system work.
Sometimes data comes directly from experiments or pilot projects (called primary data), and sometimes from databases or literature (secondary data), all combined carefully to build a complete picture.
3. Life Cycle Impact Assessment (LCIA) - Turning Data into Impacts
Now that we know what goes in and out, we translate it into how it affects the environment.
This is where we calculate impact categories such as:
- Climate change (resulting from GHG emissions),
- Acidification,
- Land Use,
- Ecotoxicity,
- Water consumption,
- Air and soil pollution,
- Resource depletion, and more (actually up to a total of 16 categories of impact!).
In other words, we turn long lists of numbers into meaningful indicators that show where the biggest environmental burdens lie.
For instance, battery production might contribute strongly to climate change, while drone charging might have a smaller effect – or vice versa.
This helps identify hotspots, i.e. the parts of a system where improvement can make the most difference.
4. Interpretation - Making Sense of It All
Finally, we interpret the results obtained in the previous step, so that we don’t just report the numbers, but explain:
- What do these results mean?
- Where are the main environmental pressures?
- How reliable is the data?
- What actions could reduce impact?
For the ICAERUS project, this is where we’ll be able to say, for instance:
“Drones show clear environmental advantages for some applications, but here’s where design improvements or operational changes could make them even better.”
This stage is all about turning analysis into insight, and insight into action.
Why It Matters?
The four stages of LCA may sound technical, but their logic is simple:
Start with a clear question, gather good data, translate it into environmental meaning, and use it to make better choices.
That’s how we make sure innovation truly moves us towards environmental sustainability, not just through clever design, but through evidence-based understanding.
