In the production of electronic devices, it is mainly the extraction and processing of metals and silicon that requires a lot of energy, and thus causes large greenhouse gas emissions. In addition, energy is required for the manufacturing of electrical components. All of the above-mentioned production steps are included. Assembly of components to finished products is however not included since this production step requires negligible amounts of energy in comparison.

Emissions can be estimated by multiplying the weight of the constituent materials by emission factors for the corresponding materials. The emission factors indicate how much greenhouse gases are emitted during the extraction and enrichment of 1 kg of material.

Electronics contain many different materials and elements, and there is a large variation in emission factors for different elements depending on how common they are in the earth’s crust and how difficult they are to extract. For example, the production of 1 kg of carbon steel emits 2.3 kg CO₂e, while the corresponding emission factor for platinum is about 34 000 kg CO₂e.

Emissions from manufacturing can be distributed over the lifetime of the product by dividing by the number of years the product is expected to be used before it is discarded. This means that the longer the product is used, the lower the emissions per year.