Council-collected food waste from across Cardiff and the Vale of Glamorgan is processed at the Rover Way site through an anaerobic digestion process. This process produces biogas, a mixture of gases produced by the breakdown of organic matter in the absence of oxygen. This gas is then used as a fuel to produce heat and electricity. We then use this electricity to power Welsh Water’s Cardiff East Waste Water Treatment Works, which equates to the same amount of energy used to power 2,000 homes.

Generating renewable energy on our sites helps us to reduce our carbon footprint. It also reduces the cost of importing energy, helping us to lower customers’ bills. Welsh Water are leading the way in generating renewable energy, and we now generate around 25% of the energy we use. We plan to increase this to 35% by 2025 and to become energy neutral by 2050.

The garden waste which is collected is processed at Lamby Way and is processed through composting. This is a natural biological process in which organisms break down organic matter in the presence of oxygen. At Lamby Way the garden waste is processed through windrow composting, which is the production of compost by piling organic matter in long rows. The waste is shredded, mixed and put into windrows which are regularly turned to regulate heat and moisture and improve oxygen content. On average this take 8-10 weeks. This compost can then be used for landscaping and building projects, production of top soil or as a soil conditioner within the agricultural sector.