In order to protect the landscape and the local area, Global Infrastructure and Networks uses specific strategies to mitigate the environmental impacts of the construction of new networks and the modernization of existing ones.
The cabling ratio is the ratio (in percentage) between the length of the cable lines and the total length of the lines. It gives an immediate indication of the mitigation of the environmental impact of power lines. The increase in this index over time is due to an increase in the length of the overhead and underground cable line to the detriment of bare conductors, with benefits in terms of network resilience, restriction of vegetation cutting and drastic reduction in the risk of electrocution for birdlife.
On a like-for-like basis compared to 2016, the cabling index in 2017 was stable compared to the previous year, equal to around 72%. The inclusion of the Brazilian distribution company Enel Distribuição Goiás in the reporting boundary (which took place in February 2017) brings the cabling index to approximately 60%. Enel Distribuição Goiás has a network of over 215 thousand kilometers, which is not uniform with the existing Enel network in the area.
The 2020 target for this index is 62%.
Storage and movement of fuel
IStorage tanks for liquid fuels (oil and gas oil with associated pipelines) and solid tanks (coal and lignite depots located in dedicated ports) are monitored with regard to the use of resources, the consumption of electricity and the production of emissions (air quality), wastewater and waste.
Sustainable construction sites
Starting in 2013, in compliance with the new framework applicable from 2015 defined by the GRI, the Enel Group began reporting the main environmental performance indicators connected to construction site activities. This category includes activities of various types and scales: from the distribution area’s yards to sites pertaining to thermal plants or the construction of new renewable hydroelectric, wind, solar, geothermal or biomass plants.
Activities have changed considerably over the years in view of the environmental aspects directly managed by the Group. Starting in 2016, reporting was carried out according to a new sustainable construction site model and the principles of the “circular economy” as it applied to all existing sites. The next Sustainability Report will include the initial results obtained from the model, to that a three-year sample can be presented and analyzed.
In 2017, the Ministry of the Environment in Santiago de Chile awarded the “Seal of Excellence” certificate to the project for the prefabricated premises of the Cerro Pabellón construction site, located about 25 kilometers from the plant. This result was made possible by a series of initiatives to improve the ecological footprint of the area of the premises, by quantifying, reducing and neutralizing greenhouse gases, using mechanisms to reduce CO2 emissions, water use and waste production.
Cerro Pabellón is located in Cile in the Atacama desert, in the district of Ollagüe, Antofagasta region, at 4,500 meters above sea level. It is the first high-enthalpy1 industrial-grade geothermal plant to have been built at such an altitude. The plant consists of two units, with a total net capacity of 41 MW.
Cerro Pabellón is a high-enthalpy binary cycle plant and features the most advanced geothermal technologies, ensuring optimal results despite the extreme local conditions where it is located, including a wide temperature range and high altitude. Furthermore, once the generation cycle is completed in the plant, the geothermal fluid extracted from the production wells is re-introduced into the subsoil, ensuring the long-term availability and sustainability of the geothermal resource. One of the unique features of geothermal energy is the ability to produce energy in a continuous cycle, 24 hours a day.
The two units started to introduce energy into the Sistema Interconectado del Norte Grande (SING) that powers the north of Chile in March and August. The inauguration, which took place in September 2017, was opened by the President of Chile Michelle Bachelet.
(1) High-enthalpy geothermal tanks are characterized by very high temperatures, above 150 °C.