A Quick Guide to Lifecycle Assessments

A quick guide to Lifecycle Assessments and using Climatiq for product and corporate reporting


Life cycle assessment (LCA) is a methodology for assessing the environmental impacts associated with all stages of a product, process or service.

Life cycle stages are typically split into three phases, often referred to collectively as “Cradle to Grave” or, when materials are recycled or reused, “Cradle to Cradle”.

  • Upstream: activities that occur in the production of the goods or services represented by the emission factor that get the good or service to the point of consumption.

    • Examples: growing crops, mining and refining fuels, manufacturing a good;
  • Use: the activity associated with the direct use of the goods or services represented by the emission factor.

    • Examples: burning fuels for heating and transportation, generation of electricity used to power buildings and machinery, processing limestone to make lime;
  • Downstream: activities that occur after the upstream and use phases associated with processing, transportation or disposal of goods or services represented by the emission factor.

    • Examples: using a courier to transport a finished good to a buyer, disposal of a good in landfill.

Product carbon footprints and corporate reporting

LCA is usually used for products, goods and services; the terms “upstream”, “downstream” and “use” above refer to the stages in a product’s life. Unless you are preparing Product Carbon Footprints or other similar LCAs for products you probably don’t need to worry about the meaning of the LCA activity terms in that context. If you are preparing LCAs then the Greenhouse Gas Protocol Product Standard (opens in a new tab) is worth reading. For other users, what is more important is where they fit into corporate reporting.

For corporate reporting under the Greenhouse Gas Protocol (GHGP) (opens in a new tab) the terms “upstream” and “downstream” refer to a company, not a good or service. They are defined by who pays for and / or provides the good or service. In general, goods and services paid for by the reporting company are upstream and those paid for by others are downstream. Upstream and downstream emissions are within GHGP scope 3. Of the fifteen scope 3 categories, the first eight (e.g. purchased goods and services) are upstream from the company and the last seven (e.g. use of sold products, end of life) are downstream.

For example, a vehicle manufacturer produces a car (the good). Under LCA reporting for the good (e.g. for a Product Carbon Footprint or PCF), upstream emissions are those arising from its production and inputs (including fuels) regardless of whether they occur in the manufacturer’s factories or from the operations of its suppliers. Use phase emissions for the car come from burning fuel in it and from its maintenance. Downstream emissions arise from the car’s disposal.

For the same car, under corporate reporting, the company’s emissions from fuel use and electricity go into scopes 1 and 2. In scope 3, upstream emissions come from the suppliers who provide the raw materials and components to make the car e.g. steel, rubber and textiles. The suppliers might provide PCFs for the goods they supply to help calculate these emissions. Scope 3 downstream emissions come primarily from the customers who use the car and also from its repair, maintenance and disposal.

For more in-depth understanding of LCA in general, you may find this article (opens in a new tab) and this website (opens in a new tab) helpful.

Using LCA activities with Climatiq

Emission factors in Climatiq’s database represent activities involved in the production of a good or service. Each emission factor or group of emission factors has a name and activity_id. Where Climatiq has data for more than one lifecycle activity for a good or service then there will be multiple emission factors with the same name and activity_id but different source_lca_activity labels.

For example, many emission factors with the name “Electricity supplied from grid” and activity_id electricity-supply_grid-source_supplier_mix have two source_lca_activity labels: electricity_generation and well_to_tank.

Our LCA activity tutorial explains what these source_lca_activity entries mean and how to use them.