# Introduction

This guide will take you through your first steps in calculating the environmental footprint of your product with Earthster. We use Life Cycle Assessment (LCA), the most rigorous methodology to do so.

# A word about Life Cycle Assessment

To get an understanding of the impact of a product, we must study its complete life cycle. That means we need to follow each of its material and energy flows from when we extract them from nature (e.g. mining of the materials), all the way to when we discard of them (e.g. when we dispose of the product).

We break that life cycle into stages, and we break those stages in the processes that they're made of. So instead of thinking of a pencil, we think of:

  • production materials like wood or graphite (and the processes that produce them),
  • production processes like woodcutting or painting,
  • distribution processes to get it to consumers, like shipping or packaging,
  • use stage processes, necessary for the product to be used, like electricity or fuel consumption, and
  • end-of-life processes that it will go through when it gets discarded.

# Let's talk about cycles

In Earthster we model any activity through cycles. Cycles represent a model of the whole life cycle of a product or service (or any other item you wish to assess, e.g. a department's operations).

Since they represent a full life cycle of a product, cycles have stages (by default, production, distribution and use). And inside each one of those stages you have all the information needed to calculate their environmental impact. The way they do so is by adding up the environmental impact of everything inside them.

Cycles are a very flexible concept in Earthster. They represent every human activity that you can imagine. Because of this, you can model a cycle to show the full life cycle impact of your product, or you can use them to represent a specific industrial process (and leave the use phase to the next person behind you). The more you add to your model, the more conclusions you can draw, but you can decide how far you'll take your cycle.