The emissions


The emissions

The greenhouse-gas emissions connected with Terna’s business come from:

  • direct consumption of energy sources (petrol and diesel for vehicles,  oil for generating units and heating, methane for heating);
  • indirect consumption of energy sources (electricity);
  • leakage of SF6 (sulfur hexafluoride), a greenhouse gas used in station equipment because of its high insulating power.
SF6 leakage is the main direct source of Terna’s greenhouse-gas emissions. From 2007 to 2009, the quantity of SF6 present in Terna’s infrastructure increased by 35 tons (+11.5%). The incidence of leakage in 2009 was 0.89%, a decrease with respect to 2008(1.07%), when, however, an incident occurred that increased the leakage abnormally.

  total direct and indirect greenhouse- gas emission , tons of CO2(1)

   2009   2008   2007 
Direct emissions      
Petrol for vehicles  506   445   582 
Diesel for vehicles  5,802   5.118   4,973 
Oil for heating and generating units   983   628   553 
Methane for heating  344   271   1,652 
SF6 leakage  71,828   81.499   50,166 
Total direct emissions
 79,464   87.961   57,926 
 Indirect emissions      
Electric energy
 75,680   69.750   71.250 
 Total emissions   155,144   157,711   129,176 

(1) The conversion of direct consumption into emissions of CO2-equivalent was made according to the parameters specified by the Greenhouse-Gas Protocol (GHG) Initiative. For the indirect consumption of electricity the conversion was made taking into account the weight of thermal production in the total Italian production of electricity in 2009. The reference for the break-down of the production mix is the December 2009 “Monthly report on the electric system”, which is available online at For 2008 and 2007, the data are from 2007 statistical data of the electric system.