District heating is a service involving the sale of heat for customer home heating and domestic hot water. It is an alternative system to traditional autonomous or condominium-based boilers which makes it possible to concentrate the production of heat in central installations, which are more efficient and better controlled than home boilers. From these installations, the heat, in the form of hot water, is brought to customer homes through a distribution network made of insulated piping. The heat then fuels the domestic heating system via non-polluting heat exchangers.
Customers have the advantage of increased safety and lower running and maintenance costs, while maintaining the freedom to independently adjust the temperature of their homes.
District heating provides a solution to air pollution problems in cities by replacing home boilers, which are sometimes fuelled by gas-oil or fuel oil, with high-efficiency heat production methods, renewable energy, or energy recovered from other production processes.
By continuing to replace fossil fuels with renewable and/or recovered energy, together with increased use of high-efficiency cogeneration plants, significant energy-environmental improvements have been achieved in the Group’s district heating plants.
During 2018, some new factors arose:
- the connection of the TLR Forlì Centro network was completed, extended with the connection of new institutional customers, to the TLR Forlì Campus network, served by the same trigeneration plant, which assumes the role of main heat production pole of the entire network now called Forlì Centro – Campus;
- in the last few months of 2018, Hera S.p.A. was awarded the GEO concession as a temporary joint venture with Enel Green Power for the direct management of geothermal wells, which will be consolidated in 2019;
- some minor systems with production from traditional boiler sources have been sold. The systems sold are Ravenna Centre and Ravenna Lama South and Cesena Islands. The plants have been sold to their original owners.
|Primary energy saved (toe)||33,776||37,450||36,495|
|Nitrogen oxide avoided (t)||296.4||300.9||265|
|Carbon dioxide avoided (t)||129,153||125,684||121,022|
|Sulphur oxides avoided (t)||278.2||295.6||268|
Calculated as the difference between a traditional system (existing boiler park comprising 65% natural gas-powered boilers and 35% diesel boilers with an average seasonal yield of 75% (Source: Comitato Termotecnico Italiano, 2009), and the national electricity grid) and Hera’s district heating systems for the quantities of energy (thermal and electric) produced by Hera. Excluding AcegasApsAmga. The emissions factors of the national electricity and thermal grid were updated in 2016.
In 2018 the plants managed by Hera saved primary energy of 36,495 toe, slightly down compared to 2017 by 954 toe (2.5% less).
As for the sources used for district heating, the percentage of thermal energy produced with gas boilers has gone down from 58% in 2005 to 31% in 2018. On the other hand, the production of thermal energy from cogeneration decreased slightly compared to that produced by boilers because, as mentioned above, in 2018 the combination of lower hourly value of electricity and the cost of gas made cogeneration operate for a smaller number of hours and therefore it provided less thermal energy.
|Thermal energy sold (MWh)||487,896||499,144||500,916|
|Volumes served (thousands of m3)||20,396||20,935||21,174|
|Housing unit equivalents served (no.)||84,987||87,231||88,225|
The housing unit equivalents were calculated on the basis of an average apartment volume of 240 m3. Excluding AcegasApsAmga.
The volume served increased by 1.1% compared to 2017 due to commercial development initiatives. Thermal energy is substantially stable compared to 2017, and is affected, in addition to the seasonality, by the fact that some systems present in 2017 were sold in 2018.