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)
|San Vittore del Lazio plant(*)||Terni plant (*)|
|pollutant||u,m,||benchmark (*)||2016||2017||2018||benchmark (*)||2016||2017||2018|
|total particles (particolate matter)||mg/Nm3||3||0.004||0.006||0.006||5||0.753||0.678||0.705|
|PAH (polycyclic aromatic hydrocarbons)||mg/Nm3||0.01||0.00001||0.00001||0.00002||0.01||<0.001||0.0001||0.5900|
|dioxins and furans (PCDD+PCDF)||mg/Nm3||0.1||0.0044||0.0047||0.0065||0.1||<0.01||0.0173||0.00005|
|heavy metals (Sb, As, Pb, Cr, Co, Cu, Mn, Ni, V)||mg/Nm3||0.5||0.0193||0.0262||0.0253||0.5||0.0263||0.1085||< 0.001|
(*) The analysis of PAH, dioxins and furans and heavy metals and their composites are four-monthly and discontinuous. The “<” symbol identifies the concentration values that are equal to or below the thresholds that the devices used by the laboratory are capable of measuring.
(**) Reference parameters, Legislative Decree no. 46/2014, 2000/76/EC and AIA, are separate for each waste-to-energy plant.
NB The figures for the San Vittore plant refer to the arithmetic averages on the two operating lines for 2016 and three lines for the two-year period 2017-2018.
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)
|assigned by NAP||actual||assigned by NAP||actual||assigned by NAP||actual|
|Tor di Valle (*)||7,969||23,313||6,869||33,507||5,805||41,946|
|Termovalorizzatore di Terni||0||112,865||0||118,653||0||114,093 (**)|
(*) As with previous years, in 2018 the applicable legislative framework allowed the Tor di Valle plant to benefit from free of charge emission allowances (5,805 t) as it serves a remote heating network.
(**) Estimated emissions, pending certification by the responsible body
126 - See www.ghgprotocol.org for more information
INTENSITY INDICES FOR GREENHOUSE GAS EMISSIONS
One of the monitored intensity indices for greenhouse gas emissions (see Table no. 67) concerns Scope 2 carbon dioxide emissions, deriving from leaks in the network for the distribution of electricity, in respect to the total electricity distributed.
This index has improved further, changing from 0.0115 t/MWh in 2017 to 0.0113 t/MWh in 2018, in line with the continuous decrease in relative leaks in the network (technical leaks/distributed electricity). With regard to other atmospheric emissions and in particular to the most significant macro-pollutants due to the main production processes of the plants (Acea Ambiente and Acea Produzione), see the summary data in Table no. 66. Compared to the 2017 data, they show substantial stability relating to NOx (nitrogen oxide) and a decrease in other types of pollutants, in particular SOx (sulphur oxide).
TABLE NO. 66 - TOTAL EMISSIONS OF ATMOSPHERIC POLLUTANTS FROM ACEA GROUP PLANTS (2016-2018)
NB The emissions refer to the following companies: Acea Ambiente - waste-to-energy plant and Acea Produzione.
TABLE NO. 67 - ENVIRONMENTAL INDICATORS: CO2 EMISSIONS, GREENHOUSE GAS INTENSITY INDICES AND VEHICLE EMISSIONS (2016-2018)
|SCOPE 1 EMISSIONS|
|FROM ENERGY PRODUCTION PLANTS|
|CO2 emissions from Acea Produzione thermoelectric plants||t||24,610||33,507||42,553|
|CO2 emissions from Acea Ambiente waste-to-energy plants (*)||t||338,552||375,159||307,160|
|FROM WASTE MANAGEMENT. ENERGY DISTRIBUTION. HEATING PLANTS AND VEHICLE FLEET|
|CO2 emissions from waste management plants||t||-||932||927|
|CO2 emissions from dryers water plants||t||-||2,026||3,381|
|CO2 emissions from heating||t||1,018||1,008||751|
|CO2 emissions from vehicle fleet (**)||t||4,891||7,371||9,407|
|CO2 emissions from Areti plants (from SF6) (***)||t||14,820||14,100||11,233|
|CO2 emissions from refrigerants (****)||t||-||-||46|
|TOTAL SCOPE 1 EMISSIONS||t||383,891||434,103||375,458|
|SCOPE 2 EMISSIONS|
|CO2 emissions from location based consumption of electricity consumption (market based) (*****)||t||349,718|
|SCOPE 3 EMISSIONS|
|CO2 emissions deriving from the purchase of goods/services and works (******)||t||17,099||24,134||23,876|
|CO2 emissions from commuting||t||3,687||3,286||4,088|
|CO2 emissions from business travel||t||197||152||160|
|INTENSITY INDICES FOR GREENHOUSE GAS EMISSIONS|
|intensity indices of the GHG emissions||(t/k€)||0.723||0.789||0.647|
|CO2 emissions (Scope 1 + Scope 2)/Acea Group added value||(g/kWh)||0.723||0.789||0.647|
|Scope 1 CO2 emissions/gross production (*******)||(g/kWh)||480.9||487.7||361.3|
|Scope 2 CO2 emissions deriving ,from losses on the electrical energy ,distribution network/distributed GWh (******)||(t/MWh)||0.0119||0.0115||0.0113|
(*) The 2016 figure for San Vittore has been corrected. In 2018, the plant’s data was measured at the chimney (in the previous two years it was calculated). The 2017 figure for Terni has been adjusted, while the 2018 figure is estimated pending certification by a third-party body.
(**) 2018 includes emissions from the fuel consumption of heavy duty vehicles used by Aquaser.
(***) These are the tonnes of equivalent CO2 corresponding to the emissions of insulating SF6 present in Areti’s HV equipment (1 t di SF6 equates to 23,500 t of CO2, GHG Protocol-5th Assessment Report- AR5): 0.478 tonnes in 2018 (0.60 x 23,500 = 11,233 t). The values for 2017 and 2018 are not comparable to those of the previous years when factor 22,800 of the 4th Assessment Report- AR4 was used.
(****) The contribution due to the replenishment of HCFC fluids in the Group’s plants was calculated for the first time in 2018.
(*****) The indirect emissions (Scope 2) include the companies within the scope of the consolidated Non-Financial Statement: Acea Ambiente, Acquaser, Acea Produzione, Areti, Acea SpA and the water companies Acea Ato 2, Acea Ato 5 and Gesesa. As an emission factor per unit of electricity consumed (t CO2/MWh), for the location-based calculation the value of 0.36 was used, as per Terna’s “International comparisons” document (October 2018). As from 2016 Scope 2 type emissions datum was also calculated using the Market Based method. The Residual Mixes coefficients are respectively for 2016, 2017 and 2018: 0.435 t/MWh, 0.465 t/MWh and 0.476 t/MWh (Source: AIB document “European Residual Mixes 2017”).
Considering the whole Group and so also including the other water companies, Gori, Umbra Acque, Acquedotto del Fiora, Publiacqua, Acque, for the sole proprietary quota part of Acea, for the three-year period 2016-2018, di Location based CO2 emissions are equal to 409,128 t, 398,287 t and 369,596 t respectively, whereas for the Market-based emissions they are equal to 494,363 t, 235,812 t and 244,750 t.
(******) This value, estimated, refers to suppliers of goods, services and works and includes transport emissions. The figure for 2017 was corrected.
(*******) Since 2018, the emissions of Scope 1 included in this index have been emissions from power generation plants. The reduction in 2018 depends mainly on the value of emissions at San Vittore, where emissions were measured instead of using the calculation used for the previous two years. The 2017 value of Terni emissions has been adjusted and is greater than what was previously published in the Environmental accounts.
(********) Network leakage considered for Scope 2 emissions and for calculating the indicator regarding the three-year period 2016-2018, are as follows: 128,388 t, 124,479 t and 120,450 t (due to the technical leakage of electricity from the network).
NB Emission factors for Scope 1 emissions are taken from the standard parameters - ISPRA data 2017, DEFRA 2018 and GHG Protocol-5th Assessment Report- AR5.
 This is primarily air conditioning equipment using refrigerant gases subject to the 1987 Montreal protocol, particularly chlorofluorocarbons