Air Emissions

Atmospheric emissions from Acea plants are carefully monitored every year. In particular, at the waste-to-energy plants monitoring is carried out by means of fixed and mobile stations that sample and analyse the fumes coming out of the chimneys, measuring numerous parameters that are periodically checked by internal personnel and certified by qualified external laboratories. In 2018, the values of the main pollutants were also significantly below the legal limits (see Table no. 64). In any case, the principle of precaution still applies, as well as attention and seeking out technological solutions with increasing performance from the issue quality viewpoint.
In 2018, surveys of odorous emissions and the monitoring of "diffuse and fugitive emissions" were also conducted, with outcomes that were not critical. The waste-to-energy plants are also managed according to UNI EN ISO 14001 standard, the OHSAS 1800:2007 standard and the European EMAS III scheme. The EMAS registration, after verification by the competent authorities during the year, has been extended until 2021. 

TABLE NO. 64 - AIR EMISSIONS FROM THE SAN VITTORE DEL LAZIO AND TERNI WASTE-TO-ENERGY PLANTS (2016-2018)

In addition to the monitoring of air quality mentioned above, at the San Vittore del Lazio waste-to-energy plant the quality of the surrounding soils and groundwater are also periodically monitored, in particular, the bioaccumulation of heavy metals on the lichen present in the soils. During the year, two monitoring campaigns of 15 days each were carried out at the two fixe control units to determine heavy metals, particulate matter (P e PM2,5) and other pollutants. The results of all the  2,5 monitoring campaigns, using both fixed and mobile monitoring devices, did not indicate excessive levels for the measured parameters. 

GREENHOUSE GAS EMISSIONS

Greenhouse gas emissions, as defined in the international document Greenhouse Gas Protocol (or GHG Protocol), aligned with ISO 14064 which was implemented in 2018, are classified into the following three types:

• Scope 1 emissions: direct greenhouse gas emissions; 
• Scope 2 emissions: indirect greenhouse gas emissions; 
• Scope 3 emissions: other indirect greenhouse gas emissions. 

Acea quantifies its CO₂ emissions by assessing the carbon footprint of individual macro production processes according to the guidelines of the GHG Protocol ¹²⁶; In fact, as mentioned above, it participates in the annual completion of the international questionnaire on carbon dioxide emissions, the so-called “CDP” (see the box in the section Mitigation and adaptation to climate change).

Scope 1 emissions are direct emissions. They mainly come from the Group’s waste-to-energy plants and thermoelectric power plants and include emissions from the heating process, dryers, generators, vehicles in its fleet (with reference to petrol and diesel engines) and, lastly, from sulphur hexafluoride (SF6) losses that can occur at Areti plants, and from freon gases in air conditioners, the latter being reported this year for the first time. As mentioned, the most significant contribution comes from the CO₂ emitted by the waste-to-energy plants. The figure decreased in 2018 mainly due to a new method of determining CO₂ emissions at the San Vittore plant in Lazio: instead of calculating the value we now have the actual data from continuous monitoring of the chimney.

Scope 2 greenhouse gas emissions are indirect, deriving from the consumption of electricity and also kept under control. In both cases, they concern emissions which Acea monitors regularly, also disclosing them, as mentioned, by means of the CDP (see Table no. 67).

Finally, greenhouse gas emissions of the Scope 3 type are represented by other indirect emissions, like those deriving from the purchase of goods/services and works, from employee travel for work and from commuting by employees. With regard to Scope 3 emissions, Acea has been monitoring its suppliers for some years now, so that they are aware of the environmental impact and estimates the data relating to the movements of employees (see Table no. 67 below). Three Group plants, specifically the waste-to-energy plant in Terni and the thermoelectric plants in Montemartini and Tor di Valle, are subject to the Emission Trading Scheme (ETS). The allowances assigned under the NAP (National Allocation Plan) framework, in respect of the actual emissions registered in the three-year period 2016-2018, are shown in Table no. 65.

TABLE NO. 65 - CO2 EMISSION ALLOWANCES AS PER THE NATIONAL ALLOCATION PLAN (NAP) AND ACTUAL EMISSIONS BY PLANT (2016-2018)