FAST DHC (Feasibility Assessment Tool for District Heating and Cooling)
The transformation of district heating (DH) and district heating and cooling (DHC) systems has been conceptualised as the transition from the 1st to the 4th generation DH networks (4GDH). In recent years, hybrid solutions of DHC and individual solutions - called temperate water loop (TWL) in France - have been introduced as a subclass in 4GDH.
In HSN, the novelty is the integration of consumer-side heat pumps (HPs), which effectively removes restrictions of system operating temperatures, as they can boost the temperature to the requirements of the service. They further enable heating and cooling (H&C) to be supplied based on one network. HPs in DHC are not new, and in fact, there are many different possible configurations; an alternative to DHC connected HPs are standalone HPs. These different options led to a (fundamental) debate within the international DHC community regarding the benefits of both systems. Although some tools for evaluating the performance of different systems are available (see section 7), they often require detailed data (e.g. hourly demand or supply profiles) and thus are not useful in very early planning stages. Other tools often do not consider all system properties (e.g. cooling or individual H&C solutions) and therefore do not give a fair comparison.
The FAST tool will allow users to input a few relevant parameters, specify H&C demand and supply options, and the economic feasibility of different network configurations can be calculated in comparison to each other and to the chosen reference energy costs (individual H&C solutions). To consider the seasonal mismatch between demand and supply, four characteristic time slots, i.e. the four seasons of the year, are considered. Whether a more detailed resolution (e.g. monthly) is possible will be decided based on data availability and reliability. The method is based on developments from the HotCity project as well as the IEA DHC annex XIII project MEMPHIS 2.0.
The FAST tool will consist of different component layers that enable setting up a specific demand for H&C and supply configuration (e.g. waste heat, rivers, geothermal collectors), as well as potential storage elements for a given district or quarter.
The aim of the project is to develop and demonstrate a simple decision support tool for the techno-economic performance evaluation of 4GDH and temperate water loops, which is also able to compare both systems to individual heating and cooling (H&C) solutions – the FAST tool.
Local authorities/municipalities: public sector stakeholders that have ambitious decarbonisation targets and are unsure of what H&C technologies may be cost-effective in their local conditions;
Consultants and energy planners: consultants are often involved in local area energy plans, which include early-stage feasibility studies of DHC projects,
and therefore play a key role in deciding what network topology is best suited for a given area/district;
DHC developers and ESCOs (Energy Service Companies): DHC developers and ESCOs could also benefit from better understanding of the merits of different DHC generations,
and this knowledge can be incorporated into the design and operation of future schemes;
Academic community: the FAST tool will provide a means of comparing the applicability of 4G
and HSN concepts and can support the work of other researchers in the field.
Deliverables and products:
a) A tool that allows users to compare the relative merits of each DHC/H&C technology, providing much better clarity on how/where each system may be used. The tool will be publicly available as an online version with a user-friendly interface. All relevant documentation will also be provided; an example of a related tool is the Flexi-Sync tool, as shown in Figure 3.
b) Test cases and feasibility studies for comparing the implementation of 4GDH networks and TTN as opposed to individual H&C technologies.
c) Target-group-specific dissemination of project results and scientific exploitation. This will leverage relevant events for the DHC industry and explore the flexibility of online platforms, as described in the communication plan (see section 9 for details).
The FAST tool should give the user an indication as to which DHC system represents the best potential investment under the assumed boundary conditions, and how it would compare against individual H&C counterfactuals.
London South Bank University (LSBU), UK
Dr. Henrique Lagoeiro
- Austrian Institute of Technology (AIT), Austria
Aalborg University (AAU), Denmark
Danfoss Climate Solutions (DCS), Denmark