Carbon footprint is a measure used to quantify greenhouse gases (GHG) emissions associated with organizations, events or activities or with the life cycle of a product to determine its contribution to climate change, being expressed in kg of CO2 equivalent. GHG emissions can be direct or indirect, derived last ones from energy consumption. In the case of the urban water cycle (which uses 3% of the total energy consumption in Spain), the emissions come mainly from the use of energy. Thus, to estimate this type of emissions it can be taken into account both, energy consumption and emission factors, these last ones which associate quantity of energy consumed and quantity of gases emitted. This work presents the result to calculate the carbon footprint related to urban water cycle of Córdoba in the last six years: 4,225.541 T of CO2 eq/year are emitted, at a rate of 12.92 kg of CO2 eq/year per inhabitant, and 0.176 kg of CO2 eq. per m3/water managed by the company. If we compare this result with the obtained in our last studied period (2012-14) which reached a value of 5,015.80 T of CO2 eq/year (-15%) and a rate of 15.2 kg of CO2 eq/year per inhabitant, we can conclude that the company has shown a relevant positive environmental balance.
The effects of urban water cycle on energy consumption in Beijing, China