201720162017-2016
“Zero-emission” generation (% of total) 43.3 45.6 (2.3) -5.0%
Total specific emissions of CO2 from net generation (gCO2/kWheq) (1) 411 395 16 4.1%
Average efficiency of thermal plants (%) (2) 40.7 40.0 0.7 1.8%
Specific emissions of SO2 (g/kWheq) (1)       0.84 0.82 0.02 2.4%
Specific emissions of NOx (g/kWheq) (1) 0.79 0.75 0.04 5.3%
Specific emissions of particulates (g/kWheq  ) (1) 0.27 0.22 0.05 22.7%
ISO 14001-certified net efficient capacity (% of total) 99.0 97.9 1.1 1.1%
Enel injury frequency rate (3) 1.20 1.25 (0.05) -4.0%
Enel injury severity rate (4) 0.058 0.050 0.008 16.0%
Serious and fatal injuries at Enel (no.) 6 5 1 20.0%
Serious and fatal injuries at contractors (no.) 20 12 8 66.7%
Verified violations of the Code of Ethics (no.) (5) 27 21 6 29.0%

(1) Specific emissions are calculated as total emissions from simple thermal generation and co-generation of electricity and heat as a ratio of total renewables generation, nuclear generation, simple thermal generation and co-generation of electricity and heat (including the contribution of heat in MWh equivalent).
(2) Percentages calculated using new method that does not include oil and gas plants in Italy that are in the process of decommissioning or are marginal among thermal plants. The figures also do not consider consumption and generation for co-generation at Russian thermal plants. The average efficiency is calculated on the basis of the number of plants and weighted by output.
(3) The indicator is calculated as the ratio between the total number of injuries and the number of hours worked, in millions.
(4) The indicator is calculated as the ratio between the number of days lost for injuries and the number of hours worked, in thousands.
(5) The analysis of reports received in 2016 was completed in 2017. For that reason, the number of verified violations for 2016 was restated from 18 to 21.

In line with the decarbonization objective for 2050, new renewables capacity totaling about 2.8 GW was installed, mainly in Brazil, Peru and the United States. However, zeroemissions generation in 2017 was equal to about 43% of total output, a decrease on the previous year that reflected the deconsolidation of the plants in Slovakia, Belgium and North America. Emissions of CO2 diminished slightly in absolute terms compared with 2016, but with a reduction in the Group’s total net generation, specific emissions of CO2 increased by 4% on the previous year (411g/kWheq).

The values for other specific atmospheric emissions rose slightly compared with 2016 as a result of the decline in output. Particulates increased by about 23%, however, reflecting the increase in coal-fired thermal generation in Russia. Nevertheless, these figures were in line with the Group’s targets for 2020.

The average efficiency of thermal plants was virtually unchanged on 2016.

The Enel Group has an environmental management system that covers almost 100% of all activities (generation plants, grids, services, properties, sales, etc.). The entire scope of operations is certified except for new plants and newly acquired or constructed installations, which require a certain amount of time for certification.

Injury frequency and severity rates for employees of the Enel Group were equal to 1.20 (1.25 in 2016) and 0.058 (0.050 in 2016).

In 2017 there were 2 fatal accidents and 4 serious accidents involving Enel personnel and 11 fatal accidents and 9 serious accidents involving the employees of contractors working for Enel.

Reports of violations of the Code of Ethics numbered 123 last year. Following analysis in 2017, 27 were classified as violations.