Energy savings

[GRI - 201-2], [GRI - 302-3], [GRI - 302-4], [GRI - 305-5],

Ecogena is the organisation registered to develop energy-efficiency initiatives for the Group Companies and report their results to the Gestore dei Servizi Energetici (GSE) for the awarding of Energy Efficiency Certificates (EECs). At 31/12/2021, the plants managed by Ecogena received 8,980 TEE pursuant to Italian Ministerial De- cree of 5 September 2011.

For Areti to achieve the energy-saving goal, actions were focused on the purchase of EECs on the market managed by the electricity market operator (GME). The 2020 requirement, with expiry post- poned to July 2021, is 54,848 EECs. On top of this, there is the residual portion of the 2019 requirement equal to 48,947 EECs with respect to the initial 122,369 EECs, and the residual portion relating to the 2018 requirement equal to 10,102 EECs. The total requirement was therefore 113,897 EECs, of which the minimum to be cancelled was 43,011, with this quantity being correctly can- celled. Since 30/06/2021 the management contract for EECs for Areti’s compliance was terminated and this activity returned di- rectly under the control of Areti.


Again in 2021, Acea launched actions aimed at recovery of ener- gy efficiency, in particular at the headquarters and the Companies of the Water, Energy Infrastructure and Environment operating segments. At the headquarters there was replacement of window fixtures in the stairwell, lift motors and various lighting fixtures with LED technology in certain offices and corridors. Energy consump- tion of the headquarters continued to be lower than the historical average, also in relation to the health emergency. At Acea's La For- nace conference centre, also used for employee training, a photo- voltaic plant is in use. This produced 10.6 MWh in 2021, with 4.2 MWh for self-consumption and the remaining 6.4 MWh issued to the national electricity grid.

Considering the photovoltaic systems at the plants of Acea Ato 2, AdF and Terni, total energy consumption (on-site self-consumption) was approximately 950 MWh, with a consequent 300 tonnes of CO2 emissions avoided.

For the Water Segment, in 2021 consumption saw a slight reduction (-2.4%) due in part to an increase in rainfall and in part to energy-efficiency measures. Below is a description of the energy-efficiency actions taken by the Companies in relation to routine operations.

In this regard, in 2021 Acea Ato 2 achieved a total saving of 8.9 TJ (2.48 GWh). In particular, consumption has been reduced for ener- gy used in the recovery of water losses in Roma, through significant measures taken to recover the resource, with a saving of approxi- mately 2.6 TJ (0.72 GWh). There have been increases in efficien- cy corresponding to 4.7 TJ (1.29 GWh) at two water plants and for the treatment segment there have been increases in efficiency for a saving of 1.7 TJ (0.47 GWh) through specific actions to optimise two treatment plants. For Acea Ato 5 increases in efficiency, cor- responding to 3.2 TJ (0.90 GWh), are attributable to the replace- ment of multiple pumps used for withdrawal at springs and well fields, installation of inverters, elimination of two treatment plants and a sewerage pumping plant, and replacement of traditional lamps with LED lamps. GORI implemented actions to increase efficiency for a saving of 62.6 TJ (17.4 GWh), primarily through use of water sources with greater efficiency, new remote-management methods and the use of electric pumps with a greater yield. AdF increased efficiency for a saving of 5.3 TJ (1.5 GWh) through actions on the aqueduct, with replacement of older pumps, district planning, management of pressure levels and leak detection. Gesesa has achieved an initial saving through increased efficiency of 1.4 TJ (0.4 GWh) resulting from actions to manage pressure levels in the context of the current district-planning process. Overall, the above actions have enabled the water segment to avoid approximately 7,130 t of CO2.

For the Environment Segment, activities to increase energy efficiency in 2021 have involved actions at the San Vittore del Lazio plant: replacement of two electric motors with new more effi-cient models on lines 2 and 3, and replacement of traditional lamps with LED lamps, an annual overall saving from increased efficiency of 151,000 kWh. Other minor actions include replacement of LED systems at the Aprilia plant (5.8 MWh), and replacement of the cen- trifuge for drying of sludge156 at the Chiusi plant of Bio Ecologia (23 MWh/year). For Acque Industriali in August 2021, the LSC-oil boiler of the Pontedera plant was replaced with a GPL system, for an annual increase in efficiency in 2021 that saved 840 kWh. 57 tonnes of CO2 emissions were avoided.

In the Networks segment, the Company Areti continued in 2021 with works to increase efficiency on the electricity distribution network managed, including:

  • the use of 257 MV/LV transformers with very low losses, which allowed a reduction in electricity consumption of 388 MWh157
  • other actions on the HV/MV/LV distribution network aimed at optimising the structure of the MV network and upgrading of HV and LV lines, currently estimated at a total of 1,127 MWh saved (including use of transformers).

Table no. 63 shows the types of actions and relative energy savings for Areti, for the last three years. In 2021, the total energy saving was 4 TJ (1.1 GWh) and 355 tonnes of CO2 emissions were avoided158.

Table no. 63 – Energy eciency in Areti (2019-2021)




2019 2020 2021

reduction in losses from the network

4.860 6.372 (*) 4.057 (**)

of which reduction in losses through the purchase of new transformers

1.454 1.141 1.397

(*) consolidated figure
(**) estimated figure

Consumption for public lighting in 2021 was 67 GWh (242 TJ), in line with 2020 consumption. The ratio of LED lamps to total lamps remained unchanged at 91.7%.

Again in 2021, a further positive contribution was provided by the 25 electric vehicles already in use in 2019 by the Company’s staff in the context of a car-sharing scheme (Renault ZOE cars). In 2020, 100 electric Renault Kangoo cars were also purchased, destined for 24-hour personal work use, assigned individually to single employ- ees. Of these, at the end of 2021, approximately 40 are already operational. In 2021, Areti monitoring calculated a total for all jour- neys of approximately 284,444 km, consumption of approximate- ly 46 MWh and a net saving of approximately 28,670 kg of CO2 linked to the absence of use of vehicles running on diesel.

Chart no. 59 – Car-sharing data (2021) (*)

Risorsa 59

(*) The chart refers to the ZOE model cars in the car-sharing scheme. It does not include Renault Kangoo vehicles assigned individually.

In 2021 Acea Ato 2 also added to its fleet of vehicles with 15 electric box trucks and completed installation of on-site charging stations at the treatment plants of Roma Sud, Ostia, Roma Nord, Roma Est and Cobis.

156 The increased eciency of performance of the centrifuge primarily enables an increase in volumes that can be processed, along with an energy saving.
157In 2021, 257 transformers with very low losses were moved from the company warehouse, partially for replacement of traditional transformers and partly to equip new MV/LV substations.
158Calculations for estimation of CO2 emissions avoided in the entire section Relations with the environment have been carried out using the 2021 Terna location-based conversion factor, equal to 0.315 tonnes of CO2/MWh. In the Sustainability Plan reporting, the same estimate is made using the 2019 conversion factor, in line with the calculation for definition of the 2024 target.