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Cool ways of using low grade Heat Sources from Cooling and Surplus Heat for heating of Energy Efficient Buildings with new Low Temperature District Heating (LTDH) Solutions.

Periodic Reporting for period 1 - COOL DH (Cool ways of using low grade Heat Sources from Cooling and Surplus Heat for heating of Energy Efficient Buildings with new Low Temperature District Heating (LTDH) Solutions.)

Reporting period: 2017-10-01 to 2019-03-31

"The COOL DH project innovate, demonstrate, evaluate and disseminate technological solutions needed to exploit and utilise sources of very low-grade ""waste"" heat for heating of energy effi-cient buildings via Low Temperature District Heating (LTDH) and show how the District Heating (DH) systems can be more resource efficient and more energy efficient.

The demonstration covers both new developments and stepwise transition of existing areas with district heating and energy retrofitting of buildings. The COOL DH consortium consists of the utilities and municipalities of the two cities Lund (Sweden) and Høje-Taastrup (Denmark), and leading District Heating energy specialists as well as leading industrial manufacturers.

- Innovate, design and build cooling and heat recovery process systems, enabling heat recovery to a local low-temperature district heating grid. The heat recovery systems will mainly be driven by renewables.
- Design and build a low-temperature district heating grid with non-conventional pipe materials and testing of new innovative pipe components introduced by COOL DH.
- Innovate and design suitable innovative heating systems and controls inside buildings that combine LTDH with distributed integration of locally produced renewable energy on the buildings.
- Develop viable business models and new pricing systems, which ensure a good (low) return temperature and provide the building companies with maximum flexibility regarding the choice of heating systems.
- Demonstrate a full system with all needed components suitable also for ultra-low DH temperatures including demonstration of systems for heating of DHW without risk of legionella.

Specifically, for the first 18 months COOL DH has:
- Shared knowledge and initiated and completed workshops and collected input to adjust the approach/plan for the project.
- Organised the innovation process and developed new innovative solutions that for a number of solutions will be demonstrated later in the project.
- Planned and initiated demonstrations in Brunnshög district of Lund, in Sweden, and in Høje Taastrup, in Denmark.
- Started the initial planning of the monitoring.
- Put the communication tasks up in momentum according to the time plan.
- Got the project up and going with a continued pace according to plan."
Explanation of the work carried per WP
In general, the project is running successfully with small modification in timeline. WP1 and 2 ar completed.
WP1 Knowledge management
Information of best practices has shared in the project. Workshops included participation of external experts from industrial suppliers, and academia. Results of the innovation work in WP2 was presented at workshops and the output hereof feeds directly into the demonstration work:

Demand side:
• Solutions for avoiding risks of legionella
• Solutions for local integration of renewables at the buildings
• Substation solutions
• System solutions for multifamily/tertiary buildings.
Water temperatures above 55oC are safe if DHW is prepared centrally and 45-50oC if DHW is prepared close to tap. Otherwise use electrochemical water treatment or chemical doze an no blind ends.

Distribution side:
• Design concepts for optimisation of LTDH distribution systems
• Pipe components for LTDH distribution systems
• Internal distribution in buildings
• Metering concepts.
TERMIS simulation with new plastic materials at up to 13 bars instead of 6 bar.

Supply side:
• Cascade couplings for optimal use of low-temperature sources
• Integration of additional renewables.

WP 2 Innovations
COOL DH has developed renewables and efficiency solutions in relation to LTDH systems:
- Solutions to avoid legionella
- Solutions for temperature topping
- Solutions for heat exchangers suitable for LTDH
- Optimal design rules forLTDH
- New pre-insulated pipe types
- Systems that handle multiple sources of heat
- Intelligent metering and control system
- Develop new generic LTDH design concepts
- Analyse heating and cooling concepts including heat pumps and a UTES system
- Prepare regulative instruments.
From the many deliverables we can highlight:
Data sheets fo anti-legionella treatment methods.
Data sheets of conceptual solutions.
New types of pipes, for use in Høje-Taastrup and Brunnshög - testing of the prototypes.
Design manual is finished to be used to train installers.

Production side has focussed on optimising cascade couplings for optimal use of low-temperature sources
Further short time and seasonal energy storage has been studied for Høje-Taastrup

WP3 Demonstration of integrated smart city LTDH system solutions in Lund
This work package started in 2019. The workis delayed mainly due to a slower development of building construction than expected.

WP 4 - Demonstration in Høje-Taastrup
This work package was started before schedule. Design work is ongoing. No major deviations identified sofar.

WP5 Monitoring and evaluation
Monitoring of energy performancefor involved plants and buildings (macrolevel)
The work start in 2021.

WP6 - Dissemination and promotion
A business plan for LTDH has been prepared for Lund with a new LTDH tariff.

Investigations of legislative framework has been studied for Denmark and Sweden incl. the changes in legislation since beginning af the project.

Website: .
Video on and on vimeo:
Webinar on innovations available on:
Newsletters shared through the DHC+ Technology Platform as well the video.
Presented at a high-level decision-maker seminar at COWI with participation of the Danish Minister of Climate, Energy and Supply and the Mayor of City of Lund

WP7 - Project management and reporting
The project is proceeding well.
Alfa Laval (IND-SE) was replaced by Cetetherm.
The saving in COOL DH is estimated at 10 GWh p.a. in Lund & 8.8 GWh p.a. in Høje-Taastrup when fully exploited.

Utilised waste heat will marginally save 300 kg CO2/MWh
CO2 savings depend on the energy savings realised

The new LTDH supply will tariffed according to actual costs,
For the case of Østerby the tenant earlier paid for the DH pipe losses and maintenance of pipes. The savings in heat loss payment alone will be 10-25%.

In Lund renewables will increase from 98% to 100%. In Høje-Taastrup renewables will increase from 51% to 90% for the served area
The emissions in Høje Taastrup is reduced to 80 kg CO2 per MWh. 66% is non-fossil. For Østerby the heat pump from CITY2 will recover cooling energy and mix this supply in the system reaching a RES for Østerby between 66 -100% depending on operation.

The heat losses in DH systems with low energy density often reach 30-35% and can be reduced to <10%
It is estimated at 11% in Østerby and lower in Brunnshög. A pilotline with zero heat loss will be demonstrated.

In DK there are >430 DH utilities and in SE >396 DH utilities with areas that can convert to LTDH.

The Danish legislation on utilisation of surplus heat has been changed during cause of the project.