The DH System of Bolzano in South Tyrol (northern Italy) was initiated in 1986 in order to satisfy a social housing district’s need for heat. From the end of the 1990 years began expansion, optimisation and from 2008 took place a massive expansion, made possible through the construction of a new waste incineration plant. Thus, a strong reduction of CO2 emission was possible despite a massive expansion of the network.
Warmtenetwerk Zaanstad B.V. has created the first open district heating network in the Netherlands in Zaanstad-Oost. This organization is a partnership between the municipality of Zaanstad, Firan, and the provincial authority of Noord-Holland. Thanks to the open structure, all suppliers and customers will ultimately be able to use the heating infrastructure under the same conditions. The district heating network, which has supplied heat to an existing residential district since 2019, is powered by a local small-scale biomass plant in this early phase. In the future, we will also be able to connect newly constructed homes and create links for new products, suppliers and users.
Odense wants to phase out the remaining 30% coal consumption in the heat
production for the district heating network by 2025. In 2018, the coal consumption was already reduced from ~900.000 t/y in 2010 to 2-300.000 t/y but the goal is to substitute this completely. To realize this purpose, electric heat pumps, large heat storages, biomass boilers, and electric boilers are constructed. The challenge is
to carry this out without price increases for the consumers, especially the greenhouse industry where
heat price is an important competition faction.
The district heating system in Zagreb is the largest in Croatia, with 1,420 MW of thermal power
installed that supply 30% of the households in Zagreb. The upgraded district heating system
is owned by TE-TO Zagreb. TE-TO Zagreb operates cogeneration plants, which provide hot
water for heating, as well as steam for industrial uses.
Within a privately owned residential building a variety of technologies are implemented to reduce the energy consumption. Both a solar heating system and heat pump are connected to a boiler for the heating of water. This water is used as sanitary hot water. Space heating and cooling is achieved from fan coil units (FCUs); where hot or cold water circulates inside the convectors depending on the need. Finally, underfloor heating is established through a closed water pipe system, with a heat pump as heating source. The monitoring of the entire system takes place in one control unit.
In the small Slovenian town Kuzma a district heating network is established based on biomass burning. The investments were made by a private company, with the financial support of the national government, and the aim of reducing energy prices in the area. The biomass used is collected from local wood owners in the neighbourhood and converted into heat by two biomass boilers. In combination with a 10 m3 storage tank for peak load no additional heat source is required to supply heating to 58 houses and some other residential buildings.
In the south of Germany a small district heating network has been installed in the town of Mietraching/Bad Aibling. The main sources of district heating are a woodchip boiler, mainly used in cold days, and solar collectors, mainly used in the warm days. The solar collectors are connected to centralised and decentralised buffer tanks for energy storage. Furthermore, a gas installation is delivering peak load for in mid-winter. The district heating network supplies heating to about 130 households, 2 schools, office buildings and a hotel.
As the district heating system in Herten is currently supplied with heat from coal-fired Combined Heat & Power (CHP), the approach was to frame a potential alternative mix of centralised heat supply units with a high share of renewable energy sources. It is aimed at designing a system which is technically feasible and to compare it to the current system with regard to the heating costs.
The city of Munich implements various policies to increase energy efficiency and to mitigate climate change. In 2007, the city of Munich realized the solar thermal heating project Am Ackermannbogen which includes 3078 m2 rooftop solar collectors, a seasonal storage tank & heat pump. The installation provides heating to 320 apartments, of which 40 – 45% solar thermal heat.