First of all, it is important to understand that the methanization process allows, in all cases, the creation of a raw product which is biogas . This is the source of renewable energy which can then take several forms depending on the technology used: cogeneration or injection.

Cogeneration allows the simultaneous production of electricity and heat from biogas. To do this, the biogas is burned in an engine and transformed into:
- in electricity, which can be used on site to power the structure or injected into the local electricity network
- into heat, which can be used to heat buildings or for other thermal uses.

Injection consists of purifying the biogas to transform it into biomethane, in particular by releasing the carbon dioxide it contained. This creates a gas that is much more concentrated in energy (methane). The latter can then be injected into the natural gas network and used as a renewable energy source for households, businesses and even transport.

In other words, cogeneration makes it possible to produce electricity and heat locally, while injection makes it possible to produce biomethane which can be used remotely and on a larger scale.