Transforming District Heating: Sustainable Solutions for Urban Energy

The Importance of Heat in Energy Consumption

When discussing energy transformation and sustainability, it's easy to overlook a crucial factor: heat. Approximately 50% of total energy consumption is in the form of heat. This makes decarbonizing the heat sector a critical component in achieving real progress towards sustainability goals.

Veolia: A Leader in Sustainable District Heating

Veolia, a global leader in essential services, is at the forefront of transforming and modernizing the district heating sector. With operations in 50 countries and over 200,000 employees, Veolia helps customers access essential services in water, waste, and energy.

In the energy sector, Veolia's business is highly localized. They produce and distribute energy while providing on-site services to help customers improve energy efficiency. In 2023, Veolia's turnover reached 45 billion euros, with 25% coming from energy-related activities.

Veolia's District Heating Capabilities

Veolia operates more than 700 district heating networks worldwide, primarily in Western Europe, Central and Eastern Europe, and Asia. Their heating and cooling services reach 7 million inhabitants, making them a significant player in urban infrastructure.

Some key cities where Veolia operates district heating networks include:

• Warsaw
• Prague
• Budapest
• Tashkent

The Heat Sector: A Often Overlooked Energy Consumer

When discussing energy, the focus often falls on electricity. However, according to the International Energy Agency's 2023 data on final energy demand, 50% of energy demand comes from heat. This includes:

• Industrial heat
• Residential heat
• Tertiary sector heat

While electricity will play an increasingly important role in future energy systems, it's crucial to recognize that not everything can be electrified. To address this significant portion of energy demand, we need to find pragmatic solutions, often utilizing local resources that are readily available but overlooked.

The Importance of District Heating Networks in Europe

District heating networks play a vital role in Europe's energy landscape, covering 13-14% of heat demand. This percentage varies significantly between countries, but projections suggest it could reach nearly 20% by 2030.

Veolia has two strong convictions regarding district heating:

1. Existing networks, including their own, can be significantly decarbonized.
2. More district heating networks can be deployed in the future.

District heating networks offer several advantages:

• They can utilize various technologies and heat sources.
• Networks can start small and expand progressively to cover entire urban areas.
• They provide collective solutions that enhance energy security and strategic autonomy.

Case Study: Sofia's District Heating Network

Sofia's district heating network, established between the 1950s and 1960s, spans 900 kilometers and serves more than half of the city's population. Like many historical networks, it faces challenges:

• High dependence on natural gas
• Inefficiencies due to aging infrastructure

To address these issues and reduce dependency on natural gas, several steps can be taken:

1. Improve Energy Efficiency

• Generation: Implement efficient technologies like cogeneration to save natural gas.
• Distribution: Replace old pipes to reduce leakage.
• Consumer-side: Encourage controlled consumption through proper tarification and incentives for modulating usage.
• Building insulation: Improve energy efficiency in connected buildings.

2. Implement New Heat Sources

Sofia's network could potentially incorporate:

• Geothermal energy: Utilize the country's geothermal potential, considering both shallow and deep geothermal options.
• Solar thermal energy: Explore the possibility of integrating solar thermal systems, as seen in neighboring countries.

Innovative Solutions for District Heating

Veolia has implemented several innovative projects to improve district heating networks, often with EU subsidies. These examples demonstrate the feasibility of implementing sustainable solutions:

Waste Heat Recovery

Example: University in Hungary

• Implemented 10 years ago
• Recovers energy from sewage networks
• Provides heating and cooling for the university
• Similar projects now reach capacities of up to 100 megawatts

Biomass and Gas Cogeneration

Example: Brag, Germany

• Fully exited from coal
• Implemented local biomass cogeneration plant
• Gas cogeneration plant for high demand periods
• Expanding to new residential areas

Data Center Heat Recovery

Example: Small project in Germany

• Recovers heat from a data center
• Uses heat pump to upgrade the recovered heat
• Supplies heat to the district network
• Funded by local and EU grants

LNG Terminal Cold Recovery

Example: Barcelona, Spain

• Recovers cold energy from LNG regasification process
• Injects recovered cold into cooling network
• Supplies residential and industrial buildings near the terminal
• Potential for replication at other LNG terminals worldwide

Cross-Border Heating Network

Example: Germany-Poland border

• Connects heating networks in German city of Guben and Polish city of Gubin
• Aims to fully decarbonize both networks by 2028-2029
• Utilizes a mix of technologies:
  • Heat pumps
  • Biomass
  • Solar thermal energy
  • Thermal storage
  • E-boilers
  • Waste heat recovery
• Offers competitive pricing compared to individual solutions
• Protects against future price shocks
• Increases network connections due to demand for decarbonized energy

Thermal Energy Storage: The Heat Battery

While discussions about energy storage often focus on batteries for electricity, it's crucial to consider heat storage solutions. With half of our energy use in the form of heat, developing efficient "heat batteries" is essential.

Thermal energy storage offers several advantages:

• Uses simple and proven technologies
• Can address both short-term and seasonal needs
• Highly efficient
• Often more cost-effective than electrical batteries

Example 1: Cogeneration Heat Storage in Poznan, Poland

• Implemented in 2022
• 24,000 cubic meter water tank
• 63 meters high
• Stores heat produced from cogeneration units
• Allows for optimized electricity production based on market prices
• Can store up to 700 megawatt-hours of energy
• Very efficient with minimal losses
• Investment cost: Less than 10 million euros
• Short payback period

Example 2: Seasonal Storage in Lebork, Poland

• Replaced old coal-based heating system
• 100% renewable energy system (excluding biomass)
• Components:
  • Heat pumps
  • Photovoltaic power plant
  • Seasonal storage
• Operation:
  • Summer: Heat pumps use electricity from PV plant to produce heat
  • Heat is stored in seasonal storage
  • Winter: Stored heat is used for heating
• 50,000 cubic meter water storage (pit thermal energy storage)
• Technology proven in Denmark (since 1980s) and Germany (since 1990s)
• Costs are declining, efficiency improving

The Future of District Heating Networks

District heating networks are essential infrastructure that often go unnoticed. However, they play a crucial role in energy security and sustainability:

• Provide price stability during energy crises
• Offer diversified energy sources
• Localize energy production and distribution

As we face an uncertain energy future, investing in secure and sustainable infrastructure like district heating networks is a responsibility we must undertake.

Key Takeaways

1. Heat accounts for 50% of energy consumption, making it a critical focus for decarbonization efforts.
2. District heating networks can be transformed using various technologies and renewable energy sources.
3. Energy efficiency improvements are the first step in modernizing existing networks.
4. Innovative solutions like waste heat recovery, biomass cogeneration, and cross-border networks offer promising opportunities.
5. Thermal energy storage provides an efficient and cost-effective way to balance heat supply and demand.
6. Localized district heating systems enhance energy security and price stability.
7. Continued investment in district heating infrastructure is essential for a sustainable energy future.

By focusing on these aspects and implementing proven technologies, cities and regions can significantly reduce their carbon footprint while ensuring reliable and affordable heat for their residents.

Article created from: https://youtu.be/73WEx1rI1Hc