HOT|COOL NO. 4/2023 "Technology and Sustainability"

DBDH publishes Hot Cool, but the main business is helping cities or regions in their green transition. We will help you find specific answers for a sustainable district heating solution or integrate green technology into an existing district heating system in your region – for free! Any city, or utility in the world, can call DBDH and find help for a green district heating solution suitable for their city. A similar system is often operating in Denmark, being the most advanced district heating country globally. DBDH then organizes visits to Danish reference utilities or expert delegations from Denmark to your city. For real or virtually in webinars or web meetings. DBDH is a non-profit organization - so guidance by DBDH is free of charge. Just call us. We'd love to help you district energize your city!

NO. 4 / 2023



Sign up to receive Hot Cool






Asbjørn Bjerregaard Pedersen 4

EUROPE CALLING By Carsten Østergaard Pedersen, Rune Kaagaard Sørensen,


By Jakob Jensen 8




Cover photo: ©MAN Energy Solutions

DBDH Stæhr Johansens Vej 38 DK-2000 Frederiksberg Phone +45 8893 9150

Editor-in-Chief: Lars Gullev, VEKS

Total circulation: 5.000 copies in 74 countries 10 times per year

Grafisk layout Kåre Roager,

Coordinating Editor: Linda Bertelsen, DBDH

ISSN 0904 9681

DISTRICT HEATING CAN BECOME EUROPE’S PATH TO AN EFFECTIVE GREEN TRANSITION Danish district heating solutions, in cooperation with industry and the electricity sector, can ensure not only meeting the goal of a 70% greenhouse gas reduction but also export solutions to Europe.

By Jesper Koch, Head of research, Danish District Heating Association

But how do we solve the dilemma? In Denmark, we must har- vest as much wind and sun as possible and partly export to our neighboring countries. We must develop hydrogen-based technologies to produce green artificial fertilizers for Europe’s agriculture and new clean fuels for shipping, aviation, and heavy land transport. DH must be brought into play here. The hydrogen-based processes emit a significant amount of heat for heating our homes. DH is already a skilled player here. Soon, CO2 capture will take place at larger waste incineration plants while green electricity can be used to refine CO2 and hydrogen into electro fuels. And the heat from the processes can be used in district heating. The Amager Resource Center is an example. Another example can be found in collaborations with the in- dustry on hydrogen production and DH. In Esbjerg and Fred- ericia – two cities in Denmark -a better business case for PtX plants is created by selling excess heat from PtX plants to the nearest DH company. This means that hydrogen factories can increase production and income. Sector integration also takes place when surplus heat from in- dustry is used in DH or when geothermal energy is used on a large scale, as in Aarhus, Denmark, in a few years. Denmark’s and Europe’s green transition and way out of nat- ural gas should be handled through sector integration, ulti- mately ensuring more societal value from our energy resourc- es. In this way, society create new green jobs and higher value from the wind turbines, and not least it contributes very much to Europe becoming carbon free.. One of the means to achieve this is extensive use of the data and digitalization provided by the DH companies across the value chain. Over 65% of Danish DH companies are already digitized, and several more will join for the benefit of them- selves and Danish society.

Today 72% of Danish electricity production and 76% of our dis- trict heating (DH)-production is green. In 2030 both sectors will be entirely based on renewable energy. The most cost-efficient way to succeed is by connecting the energy sectors, industry, transport, and production of RE fuels closely together. Here, DH becomes the central player to get a better economy in the fluctuating RE sources, excess heat from industry, carbon cap- ture process, and the production of fuels from Power-to-X. For years, the electricity sector and DH have entered a partner- ship with benefits for both parties. Now is the time for us to ex- pand sector integration. Denmark’s proud cogeneration (CHP) adventure is an excellent example of collaboration, where ex- cess heat from electricity production has provided sustainable DH to the majority of the 1.85 million households today. And the electricity sector has, conversely, benefited from great- er competitiveness in the electricity market. Many DH plants have now adjusted production to not only produce electricity but also to use electricity from especially sun and wind in large heat pumps and electric boilers. In this way, DH can deliver competitive heat and, at the same time, act as a large battery for the electricity sector, balancing large amounts of fluctuat- ing electrical energy. The integration must be expanded. In the future, the concept of sector integration will have to be expanded. This is not only due to the climate target of a 70% CO 2 reduction and the current energy crisis but also to the fact that Denmark has a unique chance to become Europe’s green energy hub. We are standing at a crossroads where supply se- curity must be rethought with a very ambitious climate objec- tive in both the Danish and European contexts. The situation with sky-high natural gas and electricity prices today is in many ways reminiscent of the energy crisis back in the 70s. Now we must free ourselves completely from energy imports from Rus- sia and, on top of that, phase out the use of fossil fuels and probably reduce nuclear power and biomass dependency in European countries.


By Carsten Østergaard Pedersen, District Energy Director.

Rune Kaagaard Sørensen, Public Affairs

Asbjørn Bjerregaard Pedersen, Public Affairs.

The EU has recast the Energy Efficiency Directive. As politics plays a crucial role in developing future district heating markets, stakehold- ers within the sector should pay notice. The new Directive integrates a more significant push for 4th generation district heating and bet- ter governance, which will influence the future of European subsidy schemes, demand for Danish know-how, and solutions within 4th generation district heating.

EU raising the bar Important news has emerged from Brussels that everyone in the district heating (DH) sector should be aware of. As part of the EU’s Green Deal, the Energy Efficiency Directive 1 has been recast in response to the climate and energy crisis. The Direc- tive sets energy efficiency roles in achieving a 55% reduction in CO2 emissions by 2030 compared to 1990, with the goal of cli- mate neutrality by 2050. Energy efficiency improvements play a major role in achieving these targets as the Directive sets tar- gets of 11.7% energy savings by 2030. This is particularly significant as we are now on track to experi- ence global temperatures far beyond the Paris Agreement 2 , in- creasing energy poverty rates and risk of sufficient energy sup- ply in the coming winter. The heating sector, which accounts for over 40% of all energy end-use in Europe, therefore, needs to deliver energy savings quickly and move away from fossil fuels 3 .

further improve energy efficiency levels across Europe. Dan- ish members of the European Parliament, Danish companies, and interest organizations have promoted an increased focus on energy-efficient DH in the recast of the Directive, which will help to deliver the energy and CO2 savings we urgently need. With Denmark’s proven track record in energy-efficient solu- tions and ‘know-how’ within DH, we should be ready to meet increased demand for our energy-efficient solution and knowl- edge soon as the Directive is implemented into national legis- lations by 2024. Most important takeaways from the Directive The European DH industry will transform within the coming years, thanks to the implementation of a new directive and the innovation that happens. This Directive comprises several note- worthy elements that promise to revolutionize how we heat our homes and businesses.

Denmark has played a leading role in driving the progress in DH. There is now an opportunity to build on this expertise to

1 EU (2023) , 2 IPCC (2023) , 3 IEA Heating (2022) ,

What are the implications for the district heating sector

Energy efficiency first in heating The heating supply must now adhere to the Energy Efficiency First principle. This signifies a critical shift towards promoting energy-efficient solutions in all planning, policy-making, and significant investment processes. It means that heating solu- tions will be assessed based on their environmental impact, and only those that meet stringent energy efficiency standards will be encouraged. Data centers to utilize waste heat Data centers that consume more than 1 MW of power are now obligated to use their surplus heat unless they can prove that it is not feasible from a technical or economic standpoint. This measure will help reduce energy wastage and thereby pro- mote its utilization through DH networks. 4 th generation heat planning Heating plans have become mandatory in all cities with pop- ulations exceeding 45,000 inhabitants. These plans will adhere to the Energy Efficiency First principle and assess factors such as low-temperature readiness, co-generation, waste heat re- covery, and renewable energy sources. Replacing fossil fuels in the energy mix There are stringent measures in place to phase out fossil fuels in DH. By 2027, 50% of all heat generated must come from renewable or waste heat sources. Additionally, the CO2 content of the delivered heat must follow strict guidelines, as specified in the table below.

The new Energy Efficiency Directive from the EU has set the stage for swift implementation, with Member states need- ing to integrate the Directive’s policies by 2024. This urgency stems from the EU’s desire to reach climate targets and reduce greenhouse gas emissions, which necessitates the immediate adoption of energy-efficient solutions.


Table 1: Allowed CO2 in district heating.


Max CO2 content


200 g/kWh


150 g/kWh


100 g/kWh


50 g/kWh


0 g/kWh

The DH sector is expected to face a surge in demand for such solutions in the short term. The Danish energy consultancy firm, EA Energianalyse, estimates that the sector’s energy-efficient exports could increase by approximately 60-80 billion DKK (€ 8-10.7 billion) by 2030 to around 260 billion DKK 4 (€ 34.7 bil- lion) in total. These projections were made prior to the recent energy crisis, and as demand for natural gas-free heating tech- nologies is rising, even higher numbers may be expected. New enhanced governance structure with the National Energy & Climate Plans will increase the effectiveness of the directive’s implementation. They will ensure continuous Member State contributions to EU-targets.

Increased ambitions and governance structure The recast directive places a greater emphasis on energy ef- ficiency, with raised ambitions to achieve energy savings of 11.7% on energy end-use by 2030, compared to a reference scenario from 2020. The governance structure in the Directive has also been strengthened, enabling the Commission to im- pose stronger sanctions on member states that fail to deliver these savings. These measures are set to significantly enhance the Directive’s effectiveness and drive greater energy efficiency in the member states.

4 EA Energianalyse (2021) , Analyse af betydningen af mere ambitiøse EU klimamål frem mod 2030 for dansk eksport af energiteknologier (

energy poverty rates, with the ability to lower the energy need- ed for supplying heat. Grundfos estimates that up to 800,000 homes in Europe can be supplied with “free” heat if the existing DH grids run by a maximum of 70 degrees C temperature. That’s why we’re promoting the need for low-temperature ready buildings in the recast of the Energy Performance of Build- ings Directive. By increasing focus on building readiness, we can achieve a cost-efficient roll-out of energy-efficient heating technologies like 4 th generation DH or heat pumps. Therefore, we strongly encourage the European Union to integrate regu- lations that promote a zonal approach for building renovation to low-temperature readiness. This will drastically increase the ability for energy-efficient improvements in Europe’s DH grids. It’s time for governments, municipalities, heat planners, and utilities to implement concrete plans to roll out low-temper- ature DH zones. For example, The Albertslund Municipality in Denmark is leading the way, already starting this transition years before the new Directive was implemented. Their am- bitious plan to deliver only low-temperature DH to municipal residents by 2026 8 is an excellent example of how we can lower heat losses and integrate waste heat and renewable energy sources already today. Enough talk. Time for implementation The time for action is now. After a lengthy process of recasting the new Energy Efficiency Directive, we must swiftly move to- ward its implementation. Climate change is not slowing down, and neither should we. It’s crucial that we rapidly increase the sustainability of the heating sector. Thankfully, both the sector and its users are embracing this op- portunity for change, recognizing its positive impact on the de- livery of heat to Europe’s population. Let’s take this chance to strengthen the role of district heating in promoting a greener and more sustainable future for all.

Germany has already planned its own Energy Efficiency Act, which, according to leaked documents, closely aligns with the Energy Efficiency Directive. However, since the Directive repre- sents the minimum requirements for national legislation, Ger- many has ample room to elevate its energy-saving ambitions further. Therefore, it is crucial that the sector advocates for higher ambitions as the Directive is implemented in Member states, which will lead to even more significant climate mitigation im- pacts and demand for energy-efficient solutions. Additionally, the new Directive will heavily influence the future of large subsidy schemes for DH in Europe. Any national sub- sidy schemes must comply with the new demands outlined in the Directive and gain approval from the EU. For example, Germany’s 3 billion € DH scheme, which is applicable only for energy-efficient DH running on waste heat or renewable ener- gy and runs until 2028, aligns with the new Directive 5 . Demand-driven temperatures as a key enabler As we strive toward a greener future, low-temperature DH zones have emerged as a key focus area. Therefore, we warm- ly welcome the integration of mandatory municipal heating plans that assess low-temperature readiness in the Directive. This is an important step towards reducing CO2 emissions, in- creasing energy efficiency levels, and integrating more waste heat and renewable energy sources into our DH energy mix. The amount of waste heat in the EU is almost equal to the needed energy for Europe’s residential and service sector buildings 6 , illustrating the vast potential. However, to fully un- lock this potential, we must focus on lowering temperatures to a maximum of 70 degrees C. Lower temperatures are more efficient for utilizing renewable energy and waste heat in DH grids, making low-temperature DH one of the cheapest technologies for achieving 100% renew- able heating 7 . This is an important step in combatting the rising

For further information please contact: Carsten Østergaard Pedersen,

“Saving energy is absolutely the best we can do to reduce carbon emissions and secure our independence! By adjusting temperatures in de-centralized city zones, you can get a much more flexible and energy-efficient district heating grid that delivers the heat energy according to the exact consumer demand. New solutions from Grundfos and other suppliers make it possible to deliver competitive heat prices for most buildings in the cities – also for areas with a low heat demand (e.g., domestic houses) and areas with a high heat demand (e.g., industrial process heating) – which increase the reach of green district heating grids. Earlier, you would typically say no to customers that did not match the conditions in the delivery system, or you would increase temperatures and thereby also increase the heat losses. Now, we need to utilize these more flexible solutions. This is of key importance in our future carbon-neutral energy systems!” Kamma Holm, Former CEO of CTR (the biggest heat supplier in Denmark) and now Founder of KH RELATION

5 EU State Aid (2022) 6 Danfoss (2023), “The worls largest untapped energy source – excess heat”


Heliac solar panels generate heat using large lenses that focus sunlight the same way magnifying glasses do. This allows the solution to meet the heat demand even in district heating (DH) networks requiring output temperatures up to 130°C. In fact, the panels may deliver 160°C if needed. The solar field heats pressurised water in a closed loop deliver- ing the generated heat to the DH system via a heat exchanger connected to a storage tank installed at a peak load station. Integrating into the network via the storage tank makes it easy to control both the output and adjust the existing heat pro- duction to balance demand and supply. The property of the pressurised water is the same as what is used in the DH pipes, i.e., without the use of glycol. Avoiding glycol eliminates environmental risks and also improves the water’s viscosity, thereby slightly reducing the pumping pow- er needed. Instead, to counter the risk of freezing, the solar field circulates the return water in its pipes. This is cheaper

By Jakob Jensen, Commercial Director, Heliac

A full-scale, 1.6 MW solar field is in operation in Hørsholm, Den- mark. It produces an estimated 1,400 MWh of heat annually for the local DH network operated by the company Norfors. Norfors’ primary heat production is based on waste incinera- tion. Norfors supplies households in five municipalities north of Copenhagen with DH. Integrated into one of Norfors’ storage tanks, the solar field re- ceives DH return water at 40°C and heats it again to 90°C-110°C before returning it to the network. The specific temperature is adjusted according to the network’s demand which typically runs on higher temperatures in the winter than in the sum- mer.

than the cost of using glycol and provides an environmentally safer solution.

Other than being able to serve high-temperature DH networks, having higher temperatures delivered enables storing more energy, e.g., in a water tank or pit storage, without significantly increasing the cost of the storage. In the end, the energy den- sity per invested capital is increased with higher temperatures. For visionary DH operators, the higher temperatures also open an opportunity to serve industrial heat users with decarbon- ised process heat for steam-driven processes. Adding industri- al process not only increase revenue but may further benefit from additional flexibility in the network.

Being able to provide heat at a stable high temperature makes the solution work well together with heat pumps (HP) for DH: HP efficiency is lower in cold weather than in warm weath- er. This affects the annual efficiency and, therefore, the entire economy. Further, in regions where electricity from wind tur- bines plays a significant role, the cost of the electricity that powers the HP is generally higher in summer than in winter due to less wind. Combining HP with heat produced by solar fields addresses the annual variation in the cost of electricity. It makes it possible to increase the yearly efficiency by using stored heat as feed-in to the HP. Solar fields are built from multiple rows, each with six panels in series, where each row can be individually controlled. This de- sign gives two advantages: First, in case of a component failure (e.g., a leak), it is possible to shut down a row for maintenance without shutting down the entire solar field – resulting in less maintenance downtime. Second, in contrast to standard flat panel solutions, it permits optimizing the economics of solar fields by designing them with a peak power larger than the maximum offtake. Such a design will increase the total num- ber of decarbonised MWh delivered. The optimal design will balance the extra cost of a larger solar field with the value of reduced exposure to carbon emission taxes and the value of the efficiency increase of heat pumps. Considering the cost of carbon emission permits, distribution and transmission, and boiler losses, solar fields may prove prof- itable even in regions with limited solar irradiation. This is be- cause these costs bring the total cost of fossil-based energy to €80 (natural gas) - €95 (coal) per MWh cost at today’s prices (April 2023). Solar can compete with this cost in most places in Europe.


Initially tasked with creating yogurt-repellent struc- tures for a dairy manufacturer, Inmold - Heliac's par- ent company - developed a quick and cost-effective method for producing microstructures in plastic. This technique was later realized to be applicable to man- ufacturing microstructured Fresnel lenses, originally invented for lighthouses over two centuries ago. Heliac was founded to capitalize on this discovery and bring this technology to the commercial market. These lens- es are capable of focusing light with the same efficien- cy as traditional magnifying glasses. Based north of Copenhagen, Denmark, Heliac has 50 employees. The company holds several patents pro- tecting its invention.

For further information please contact: Jakob Jensen,

District heating needs a green transition – but how can we achieve a cost-efficient tran- sition process? A literature review has shown: There are several scientific approaches to developing theoretical heat strategies. However, when it comes to implementing and operating district heating systems, no systematically developed methodology facilitates the green transition over its lifetime. BOOSTING GREEN DISTRICT HEATING TRANSITION

By Peter Lorenzen, Ph.D. in industrial engineering,

As a further result of this research, available methods, technol- ogies, and tools were clustered to these DH scopes. Finally, it was identified that there is no comprehensive methodology for the scope of the organization, design, operational planning, and operation that aligns the related activities so that all facili- tate the green transition.

In Germany and many other European countries, natural gas has been seen as a climate-friendly substitute for coal and oil. But it is neither an emission-free technology nor a low-cost alternative (since February 2022). To achieve the climate tar- gets with large social support, we need a fast green transition in the heating sector, which is economically affordable to all consumers. Although the green transition of district heating systems (DHSs) started years ago, there are still barriers to a beneficial integration of renewable (combustion-free) heat sources. This derives—at least partly—from the existing business logic that is based on the established fossil technologies and their high temperatures. Therefore, the objective of my dissertation was to develop a methodology that facilitates the green transition cost-effi- ciently. The result is a framework that aligns relevant activities in the scopes of design, operative planning, and operation by technical and economic mechanisms. This article presents an overview of the main development and results. Lock-in to high temperatures Established technologies in DHSs are mainly based on the com- bustion of fuels like coal, oil, gas, and non-biomass waste. These combustion processes can produce high supply temperatures. In contrast, most renewable technologies—such as heat pumps, solar-thermal plants, geothermal plants, and surplus heat from industry—are not able or not cost-effective to produce heat at high temperatures. This leads to a lock-in effect of the estab- lished business models at high temperatures (figure 1). Identifying structural challenges in the lifetime of a DHS Structural challenges were analyzed from a systemic perspec- tive to resolve this lock-in effect. To do so, a systematic litera- ture research was carried out to identify the fields of activity. Figure 2 summarizes the specified DH scopes.

There is no incentive for temperature reduction

Conventional (combustion-based) heating plants only marginally benefit from lower supply temperatures

These effects result in a lock-in effect of established businessmodels of conventional heating plants with high temperatures.

Renewable (non-combustion based) heating plants are not competitive at high supply temperatures

Figure 1. The log-in effect of high temperatures The figure illustrates the lock-in effect of high system temperatures. Since conventional plants do not benefit greatly from lower system temperatures, there is no significant incentive to reduce the temperatures in existing DHSs with high temperatures from conventional heating plants. At the same time, the high temperatures impede a cost-effective connection of renewable (combustion-free) heating technologies. And if no renewable heating technologies are connected, there is no direct benefit from reducing temperatures in the existing system.

This article is based on the research presented in the Ph.D. thesis’ A Comprehensive Framework and Associated Methodology for the Design, Operative Planning, and Operation of District Heating Systems to Facilitate the Transition Towards a Fully Renewable Heat Supply’. Figures are reused from the thesis and the defense presentation.

I. Preconditions (social demands, resources, environmental conditions) II. Policies

(supernational, national, regional legislation, regulation)

III. Heat strategy (long-term visions/plans, initiating, financing) IV. Organization

(institutions, business models, ownership, pricing)

V. Design (constructions, investments, contracts, enhancements) VI. Operative planning

(optimization, schedules, interaction with other markets)

VII. Operation (controlling, monitoring, fault detection & treatment) VIII. Evaluation

(data processing, energy balances, billing)

Figure 2. Activities in DHS clustered into eight DH scopes. The figure depicts the developed DH scopes. Each of the eight scopes represents a field of activities that accompany a DHS through its lifetime. The scopes are related to each other. In the implementation process, the higher-level scopes define the conditions for the other scopes. In the bottom-up direction, there is no direct impact. Instead, learning cycles should be implemented to adjust the requirements in a transition-facilitating way.

Competition enables a green and social transition. One of the most relevant decisions in the scope of the organization is the question if competition should be allowed inside the DHS. It is important to integrate renewable technologies while optimizing the long- term total costs of the system to fulfill the objective of a low-cost and socially green transition. To do so, DHSs must be developed as economically efficient as possible.

For example, established (monopolistic) companies can rest on the lock-in effect of high temperatures, which reduces the pressure to change to new tech- nologies 1 . Further, since some of the latest technol- ogies are very complex and require a great deal of expertise (e.g., deep geothermal plants), their market introduction has high costs when the individual ex- pertise of each DH company is low.

Under these conditions, it seems rational to introduce competition to DHSs from a macroeconomic per-

1 This discussion is slightly different for regulated environments such as in Denmark compared to competitive environments with monopolistic structures such as in Germany. However, allowing third party access would be beneficial in both environments.

Capacity market

Heat producer

Constraints (e.g., network dimensions)

Long-term contracts (CFD)

Heat producer

Day-ahead market


Single buyer (System operator, network operator, market operator)



Intraday market

Obligatory participation





Figure 3. Proposed organizational structure The proposed organizational structure includes three types of agents. The single buyer is the network owner and operator of the entire system. Unbundled heat producers produce the heat. The customers are supplied by the single buyer, but they receive a separate bill for heat production and network operation.

The solution: A new framework The framework is built upon the experiences from current planning and operation processes identified by literature re- view and interviews with Danish DH companies (figure 4). The single buyer enters long-term contracts with independent producers in the capacity market. By this, the single buyer se- cures the heat supply and reduces the investment risk for new producers. Participation in the capacity market is optional for the pro- ducers. Participation in short-term markets is obligatory for all producers. Producers that only participate in the short-term markets must pay a connection fee. Continuously evaluating and adjusting the heat sources Independent from the organizational form (introducing com- petition or not), heating plant capacities, the network, and sub- stations must be planned, built, and changed. In the process of transition, legal and economic conditions are continuously evolving. It is, therefore, necessary to evaluate regularly if the DHS still meets the requirements and supplies heat under the best economic conditions. This evaluation of the financial sit- uation is done by the capacity market in five phases (figure 5). The objective of the capacity market is to minimize total costs by balancing investments into the network and customers or the heat supply. The network operator should secure a mini- mum capacity to reduce some producers’ market power and their investment risk in new plants. Further, annual environ- mental targets and the scheduling of seasonal storage should be considered. Figure 4. Main elements of the new framework As the first element of the framework, a capacity market is introduced to solve the issues of the design scope. It is connected to the short-term markets by long-term contracts, including a contract for differences (CFD) mechanism. In the short-term markets, two routines are implemented: a day-ahead and an intraday market. Finally, the resulting schedules are used to control the plants in operation.

spective: By allowing independent heat producers to connect plants to different DHSs, the economy of scale and scope can be used to reduce the heat production costs on a national scale. Thereby, companies from other sectors can bring their expertise to the DH sector (e.g., oil companies building and operating geothermal plants). Companies may focus on single technologies while up scaling the number of plants. Due to these and further qualitative arguments (presented in the dissertation), a single buyer model for DHSs is proposed to introduce competition (see Figure 3). With this new struc- ture, the core business of the DH operator changes from selling heat to reducing the total costs while meeting the ecological requirements.

Even though many advantages can be identified by introduc- ing competition, some challenges arise with it:

The single buyer and the customers risk that the independ- ent producers might take advantage of their market power on the small-scale DHS (compared to the electricity system). On the other side, there is an investment risk for the produc- ers to build new plants since there might be another new plant that may produce cheaper in the future. The overall system might suffer from suboptimization, which means every agent will try to optimize its subsystem, which can work against the overall optimum.

A framework was developed to solve these issues and weaken the arguments against competition in DHS.

1. Obtain offers Tendering

2. Scenario evaluation Total cost optimization

Independent producers

3. Detailed design Test by simulations


5. Contracts For new producers (and customers)

4. Concept validation Test by market algorithms & simulations

Fig 5. Capacity market process The capacities are planned in five phases. In phase 1, offers are obtained from independent producers. In phases 2-4, the optimal set of the different offers for supply is developed, designed, and tested in an internal iterative procedure. In phase 5, contracts are entered..

Cost-optimal operation of the plants If the ownership of the system is split into multiple companies, suboptimization must be avoided in the operative planning. Therefore, the cost-by-cause principle is introduced to the short-term markets:

When long-term contracts are entered, flexible pricing mecha- nisms must be used. This includes two price elements–one for capacity (thermal power) and one for thermal energy. Both must consider price revision clauses to allow long-term adjustments of costs. Once a contract is entered, the single buyer will pay the thermal power price for the whole duration of the contract. The energy price element is based on the contract concept for differ- ences to allow for short-term price adjustments. This energy price will only be paid if the plant is selected at the short-term markets.

Besides the costs for production, the costs for transportation (electricity demand of the pumps) should also be considered.





















Figure 6. Smart market dispatch model Smart markets consider physical effects that induce costs in the market clearing algorithm. The DHS is transferred to a dispatch model based on nodes and edges. Energy centers and customers are connected to the nodes. The edges represent the pipes, including the costs for transmission, heat losses, and temperatures. This model is used inside the smart market to minimize the variable costs, including all cost-causing effects.

DHSs. The framework for design, operative planning, and oper- ation depicts a target system for the transition in existing DHSs and can work as a blueprint for new DHSs. These contributions align the relevant activities in a transition-facilitating and eco- nomically efficient way. Different stakeholders, such as policy- makers, municipalities, and DH companies, can apply them. Since the development was limited in time and scope, fur- ther innovations are needed. For example, the advantage of introducing competition to accelerate the transition requires further evaluation on a macroeconomic level. It should con- sider the effects of the economy of scale and scope if com- petition were introduced on a national or even supernational (EU-wide) level. Further, the proposed concepts require further implementation. For example, the smart market dispatch model must be implemented and tested. Such an exemplary implementation is done in our current research project “Inte- grierter Wärmemarkt (Iwm)” [ iwm-waermemarktplatz/]. Finally, the entire framework re- quires a practical implementation.

By giving the supply temperature a price, the DHSs may be operated with locally different temperatures. This enables the operator to optimize the supply temperature considering the demanded temperature of the customers, heat losses, ther- mal stress, costs for temperature production, and network ca- pacities.

To include these effects in the short-term markets, the principle of smart markets should be applied, as depicted in Figure 6.

Finally, these market routines are combined with a complete control and monitoring platform to control the relevant actu- ators for the system’s temperature, pressure, and flow rates. In case of deviation, this system control must be able to differ from the market results to keep the system stable and effi- cient. Conclusion The research shows that existing DHSs have a lock-in to high temperatures. Operators have only a low incentive to reduce these temperatures if existing (combustion-based) heating plants are still beneficial. The literature research identified that no comprehensive methodology is available to solve this issue from a systemic perspective. Therefore, concepts were devel- oped to contribute to research and practice.

You will find the thesis on which the article is based here:

The presented eight DH scopes provide an orientation for all stakeholders involved in the transition or implementation of

For further information please contact: Dr. Peter Lorenzen,

Peter Lorenzen

What makes this subject exciting to you? In practice, I have seen many internal processes designed by people only considering their individual perspectives. Usually, a systematic evaluation of the interference of all processes in a way that facilitated the green transition was missing. So, I particularly enjoyed looking at the different processes and activities from this generalist perspective. In addition, I liked the fact that this topic is so multifaceted and complex. It encompasses many different disciplines and connects innovative technical tools and best practices. What will your findings do for DH? Specifically, my findings can be directly applied to the daily DH business. The eight DH scopes have the potential to cluster different research topics and give an orientation of current tools and methods. The new framework depicts a target system for design, operative planning, and operation. All the different contributions shown in the dissertation align the relevant activities in a transition-facilitating and economically efficient way. Furthermore, I think that the issue of competition in the district heating sector is seen as negative by many companies. However, I see it as an excellent opportunity to build more knowledge and more efficient processes. The entire DH indus- try would benefit from this and make district heating a pioneer in the green transition, also in economic terms. I would be delighted if my dissertation could provide an impetus for a factual discussion of competition in the DH sector.


By Jens Rasmussen, Technical Manager, Isoplus and Sabrina Fröhlich, PR Head of Marketing, Isoplus

Sustainability has gained increasing attention and importance in society, including the energy industry. Besides the topic’s importance for district heating providers, the sector aims to contribute to it in the most feasible way. If a pre-insulated pipe network is produced following the EN standards, the customers can expect a very long thermal lifetime. This means choosing a pipe system today is choosing it for the next generation.

How can it be ensured the products meet the expectations and demands of the next generation of young people, and what are these? In the article “ The District Heating business model 2050 – pos- sible pathways “, published by DBDH (Danish Board of District Heating) in the HOT|COOL magazine, a group of mixed stake- holders attempted to understand possible future customer values and business models for district heating. Some of the main outlooks of this study were: Heat supply is completely decarbonized, and it is standard to recover waste heat of both high and low temperatures. We live in a circular economy and, because of circularity, coupled sectors A high level of digitalization is standard See the article “The DH business model 2050” in the HOT/COOL magazine, issue no. 3, 2023, published by The Danish Board of District Heating (DBDH) How can manufacturers of pre-insulated pipes contribute to these expectations? 1. Ensure the feedstock delivered downstream within the supply chain has the lowest possible carbon footprint. To ensure a long lifetime, pre-insulated pipes are standard-

ized products of very high quality, and this should never be jeopardized. All initiatives concerning design and material properties must fulfill the requirements of EN13941-1. A new concept has recently been introduced, offering a solution for a more environmentally friendly PE outer cas- ing. It aims to reduce the carbon footprint caused by district heating networks worldwide. The raw material used for this solution is a zero-carbon alternative to traditional fossil-based PE, and it is set to change the production and use of PE in the district heat- ing business. When energy utilities choose this concept, they get the same high-quality PE as they are used to. Still, they get ISCC certificates guaranteeing that the same amount of PE is produced from renewable sources such as plant-based waste materials and used cooking oil for the bought PE. With the ISCC-certified PE, you spare the environment 1.9 tons of CO2 per ton of PE* compared with PE based on fossil raw materials, even without compromising the EN 253 norm. The solution is based on the mass balance principle – a major benefit. The CO2 savings were calculated based on the rules laid down in the ISO standards on LCA: ISO 14040:2006, ISO 14044:2006, and ISO 14067:2013

2. Ensure the production process respects the environmen- tal impact and ensures the upstream transport of the products has the lowest possible carbon footprint. The most critical elements of ensuring this are: Electrification of the production and internal transport

network can also forward information other than the alarm measurements, such as water level in wells or oth- er critical champers, temperature, pressure, and flow. c) Transmitting information via the cu alarm wires embed- ded in the PUR foam. It is even possible to embed a sepa- rate wire for separate information for all kinds of characters. d) Quality assurance of the casing joint installation The documentation and quality control for installing cas- ing joints must be digitized. The sense and possibility to incorporate the collected digitized data into a GIS sys- tem should be investigated for a fully integrated quality system of the casing joint installation. e) District heating stakeholders should have the possibility to access calculation programs online. Manufacturers of pre-insulated pipes for district energy should offer this service on their website. It should allow the calculation of optimized dimensions of the steel carrier pipe and the insulation series. 5. Produce products that can transport energy with the lowest possible environmental impact. The heat loss of a district heating network causes a consid- erable CO2 footprint, and it is imperative to focus on its re- duction in the network. This can be done in many ways, and choosing the right pipe system is crucial. If comparing the heat loss of a single pipe to a double pipe, the choice seems obvious. The below figures show the sav- ings in heat loss for dimensions ø88,9 to ø219,1 series 2 sin- gle and double pipe is between 36% - 52% Conclusion: Many relevant aspects must be considered to choose the right pipe network for the next generation. The quality of the pipe system with an optimum service life is essential. A long service life ensures the operating costs and protection of the environ- ment. Buying EHP-certified products, ensuring all products ful- fill EN13941, buying from an ISO 9001-certified manufacturer, and ensuring a correct static design of the pipe network as- sures all this. In addition to quality, environmental aspects must be considered. Besides the carbon footprint of the product, the production process and transportation of the feedstock and finished products must be analyzed, as the environmental im- pact within the production process, such as handling of chem- icals and waste.

Heating coming from sustainable local suppliers Increase transport by train whenever possible Fulfillment of the ISO 14001 certification

The initiatives mentioned above must be an aim for the en- tire industry. The more that is accomplished in this regard, the more focus can be placed on downstream supply chain efforts to develop and deliver sustainable products. 3. Secure that the products are recycled for the right purposes. Besides enabling the usage of recycled feedstock, recycling the pre-insulated pipe systems after their lifetime must be improved. What are the recycling possibilities for the com- ponents of pre-insulated pipes? PUR foam Both manufacturers of pre-insulated pipe systems and sup- pliers of the feedstock for foam are researching the possi- bilities of recycling the PUR foam of the pre-insulated pipes after the end of its lifetime, so far without a breakthrough solution for full-scale production. PE outer casing To ensure the quality and lifetime of the PE and in accord- ance with EN253, only non-degraded rework from the man- ufacturers’ own production process can be recycled and lead back to the new PE outer casing production. With a constant demand increase for sustainable prod- ucts, recycled PE from the manufacturers’ own production doesn’t fulfill the market demand, and the overall availabili- ty of feedstock from recycled PE is decreasing. The introduced more sustainable concept meets these requirements without compromising the EN253, and the availability of feedstock for plant-based waste materials is not challenged either, according to the suppliers. Steel pipe Steel accounts for the largest carbon footprint contribution in producing pre-insulated pipe systems. EN13941-1 regu- lates the quality of the steel pipes needing to be graded P235GH. Many steel mills already provide the market with pipes of steel grade P235GH with a considerable amount of recycled steel. Still, there should be a way to reduce the carbon footprint. The steel pipe manufacturing industry must focus on elec- trifying its production operations, ensuring a sustainable power source. 4. Focus on digitalization wherever possible. To support digitalization within the industry, the possibili- ties, among others, are: a) Alarm systems for surveying the network condition con- cerning if there is a leakage on either the PE outer casing or the steel carrier pipe. b) Transmitting information from alarm boxes via the GSM network. Alarm boxes sending information via the GSM

For further information please contact: Jens Rasmussen,

Dimension steel ød mm

Heat loss single pipe W/m trench

Heat loss double pipe W/m trench

Savings heat loss W/m trench

Savings heat loss in %
















Pre-assumptions: Flow temperature = 110°C Return temperature = 80°C Soil temperature = 8°C Normal soil conditions Soil covers 800 mm

λ 50 Values of the PUR foam = 0,025 W/mK (new value) 1% saved kW means saving 1% of the CO2 emission, no matter what fuel is used for the boiler.

Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16

Made with FlippingBook - Online magazine maker