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Emissions of greenhouse gases

The A2A Group’s activities emit CO2 into the atmosphere both directly (for example during energy production) and indirectly (through energy consumption at plants and offices, the use of consumable goods and materials, etc.). Nevertheless from a global standpoint the management decisions taken and the technologies used by the A2A Group can contribute to a reduction in CO2 emissions at a local level. This is the case for example with cogeneration, energy recovery from waste and energy production from renewable sources.
The performance achieved on (direct and indirect) emissions is set out below, together with the benefits in terms of avoided emissions and energy savings.
Total emissions from the production of electricity and thermal energy (see the section in the attachments: “The numbers of the environment”) represent a portion of the order of 4% of national emissions (national emissions from the production of electricity and thermal energy in 2009 amounted to 104,888,000 tonnes - source ISPRA National Inventory Report 2011).
The total average CO2 emission factor for the A2A Group, calculated by adding together all the emissions from the production of energy and taking this as a ratio of total energy production, was 353 g/kWh11 (36712g/kWh in2010), an improvement, therefore, of approximately 4% over last year.
The average emissions of A2A’s thermoelectric park were 540 g/electric kWh, similar to the national average (2009: 545 g/kWh – source ISPRA National Inventory Report 2011).
The average emission factors for the A2A Group for the various production technologies are reported in the attached tables at page XX.
The specific emissions from the waste to energy plants are liable to change, also due to the variability of the features of incoming waste. This is the case for the Brescia waste to energy plant that in addition to urban waste, which has an almost constant composition, also treats a portion of special waste and biomasses. In 2011 less paper industry pulper was treated (this consists of a portion of plastic materials that can even exceed 90%) and a greater quantity of urban waste or fuel derived from waste. As a result, the emission factor per kWh fell considerably because a higher quantity of organic (“renewable”) carbon was burnt which conventionally gives rise to nil emissions of CO2. This improvement in the emission factor is also due to measures taken to increase the efficiency of the energy recovery achieved.
One of the objectives that A2A sets itself is to limit the emission of greenhouse gases which are generated in the waste decomposition process. The “biogas” is in fact for the most part made up of methane, which has a heating power that is 25 times that of CO2.To reduce the emissions of methane into the atmosphere, A2A builds biogas capitation (breather) wells, where the gas is burned off in a flame. In certain cases energy is recovered from burning the biogas, avoiding the CO2 emissions that would be generated by producing the same quantity of energy using fossil fuels.

11 The indicator does not have a direct connection with the requirements of Directive 2003/87/EC (Emissions Trading Scheme).
12 The figure stated in the 2010 Sustainability Report (368 g/kWh) has been adjusted.

Avoided emissions and energy saving

The method of calculating the avoided emissions of CO2 and energy saving applicable to all of the Group’s plants and energy processes located in Italy has been reviewed and revised and the new method applies to the 2010 figures onwards.
The method has been extended by adding a definition of the criteria used for processing the data in order to calculate the associated avoided emissions of CO2 per kWh distributed with district heating in a predetermined sphere - network, system of networks, entire Group company, entire A2A Group - that depends on communication obligations. The emission factors and average specific consumption for national thermoelectric production used as a reference in the calculations (Italian Greenhouse Gas Inventory – National Inventory Report 2011  - 545 gCO2/kWh - and the Terna data for 2009, the same reference year as the ISPRA report) have been updated.
The methodology represents an agreed means of quantifying and communicating these environmental benefits to stakeholders by providing homogeneous information even if it originates from distinct businesses within the Group.
The method forms part of Scope 3 of the GHG Protocol and has been created as a means of reporting the annual data of the plants in use and of making forecast analyses for planned plants. Further details may be found in the previous edition of the Sustainability Report.
The results of applying this method are set out in the following table.

 Avoided emissions
(tCO2eq)
Primary energy saved
(toe)
 201020112010 2011
Cogeneration plants with district heating using fuel other than waste and with a possible heat pump section
29,975  40,161  20,985  20,653 
Energy enhancement from waste (waste to energy plants) 1,047,454  1,100,089  283,767  294,271 
Electricity production from renewable sources 1,871,067  1,691,035  621,386  600,595 
Non-cogeneration thermoelectric production 94,274  28,841  176,221  33,366 
Total 3,042,770  2,860,126  1,102,359  948,885 

The main contribution to the level of avoided emissions comes from production from renewable sources, mostly hydroelectric, which for A2A represent around 30% of the Group’s electricity production.
The figures show that waste to energy treatment plays an important part in contributing to greenhouse gas reduction objectives. It should be emphasised that A2A plants receive waste that cannot be recovered in other ways and for which, therefore, the alternative to this treatment is the landfill. The lower emissions of CO2 equivalent are above all due to the non-dispersion of biogas by the respective landfill.