District Heating (DH) systems present a high potential for the transition of the heat sector to a decarbonized ecosystem. DH allows the integration of renewable energies, improving the overall energy efficiency and help to the sector coupling. However, many DH systems need to be continuously upgraded so that they are efficient, have zero emission, and thus, contribute to mitigate climate change.
The UN estimates that 68% of the world's population will be urban in 2050. The population living in urban areas will have added 2.5 billion people worldwide by 2050. The actual and future urban development would need to be sustainable and resilient if we want to maintain the carbon neutral objectives and DH are the most suitable solution to achieve it.
The District heating generation: A solution to get smart
Smart urban development requires long-terms additional projects, such as the adaptation of energy supply, the provision of new mobility solutions and the full participation of stakeholders. They should go beyond the individual project and include the cities environment singularity. In contrast to the new building, interventions in the building stock have many restrictions and associated obstacles have to be overcome.
The implementation of new generation DH projects should be developed in an integrative way from a technical and an economic point of view. This approach is the main issue that need to be discussed fairly from a long-term aspect because short pay-back could not be applied to the economic modelling processes. Environmental protection need to be based on the long-term economic pay-back based on renewable energies usage even more expensive in a first step.
The new DH generation will improve a better integration of the available heat producers and consumer to the network making possible a bidirectional operation itself. These new revenue incomes will create new criteria on the P&L of the private companies or the local authorities and will make more profitable utility provider business with lower prices to the consumers. Definitively all these environmental benefits will redound on our society well-being.
The business model for a smart District Energy system is very project specific. It needs to ensure that all the players involved – including investors, owners, operators, utilities/suppliers, end consumers and municipalities – can achieve not only financial returns, but also other benefits that they might seek.
Public sector involvement can be crucial coordinating diverse projects with a Smart citywide vision.
What is 5th generation’s district heating?
Renewable energy sources for cooling and heating systems have increased in recent decades, but they have a fluctuation problem. Specific energy consumption in buildings and the supply/return temperatures have reduced. This means that the district heating and cooling system as previously conceptualized needs to be overhauled. The development path from the actual generation DH system to a better one is referred to as 5th generation district heating.
This development must take into account smart energy system, which also covers building HVAC systems, industrial processes and electricity. That means that the installations must be flexible enough to accommodate the future of a smart setup. These and other requirements give rise to several properties of the generation as studied by experts. Here are some of the characteristics of 4GDH or 5GDH and cooling systems:
- Supply of low-temperature DH for domestic hot water and space heating
- Distribute energy in the system with minimal grid losses
- Recycle energy and integrate renewable energy sources
- Combine with smart energy systems
- Appropriate planning and establishment of cost structures in readiness for future sustainability of energy systems
- More sizeable energy storage
- Promote CHP usage for heating energy conversion, apply heat pumps to increase network efficiency and use it simultaneously with cooling demand.
How the 5th generation district heating contribute to develop a circular economy?
Achieving sustainable modern district cooling and heating begins with the energy source. New-generation district heating and cooling systems lean towards decentralized generation of cold and heat, taking advantage of all available local energy sources.
Some local authority’s polities focus on the research of the following points to create and promote circular economies:
- Research of low grade heat dissipation from industrial or residential heat
- Promote the usage of sewage water heat or waste heat from water treatment plant
- Increase the use of waste energy
- Promote the usage of local biomass from sustainable production
- Integrate low grade geothermal energy where is possible
- Increase solar thermal energy as part of the complete DH network
- Combine wind energy and solar PV energy supply to the heating devices (Heat pumps or boilers)
- Increase TES usage to reduce significantly the grid energy consumption
- Promote the role of new consumers. The prosumers = producers & consumers
The new network concept is based on an open system where all the actors could be producers or consumers of heating energy. This optimizes the total heating generation system and reduces the total energy demand of the network.
In a society more and more connected Data Centers will be one of the most common solutions to provide low cost heat to the grid?