USAID ESP and representatives of district heating (DH) utilities discussed approaches to heat accumulation and solutions that foster the decarbonization of centralized heat supply systems

May 31, 2024

More than 200 representatives from local authorities and district heating (DH) utilities participated in the workshop arranged by the USAID Energy Security Project (ESP) jointly with the Ministry for Communities, Territories, and Infrastructure Development of Ukraine. The workshop focused on issues concerning heat accumulation, integration of renewable energy sources (RES), technical solutions as well as the technical and economic impact on heat supply systems and purposes of their usage.   

During this third workshop in a series of nine workshops on the improvement of district heating (DH) system efficiency, the participants discussed various approaches to heat accumulation and solutions that foster the decarbonization of DH systems following the principles of the EU energy law and the REPower EU Plan. To meet the EU goal concerning the transition from fossil fuels to RES, the development of efficient DH infrastructure is accelerating and growing throughout Europe and will be an important part of Ukraine’s DH development in the coming years. 

In his welcoming remarks, Michael Trainor, the USAID ESP Chief of Party, noted that heat storage systems are important to enhance the sustainability and efficiency of DH systems and for the achievement of decarbonization targets. At present, ESP provides support to six cities in Ukraine to develop heat supply schemes that will incorporate efficiency criteria for DH infrastructure, introduce distributed generation, including RES, and expand heat storage in DH systems. Besides that, ESP is developing project design documentation to install a heat storage system at one of Kyiv’s combined heat and power plants (CHPs). EBRD intends to finance this investment. 

Vadym Matkovskyi, the USAID ESP District Heating Economist, familiarized the participants with the key European trends and prospects of heat accumulation to decarbonize and improve the DH system efficiency. He said that following the requirements of the new EU Directive 2023/1791 on energy efficiency, decarbonization is required for systems that supply consumers thermal energy with a maximum volume of greenhouse gas emissions at the level of 0 g/kW·hour per unit of thermal energy. It means that efficient district heating refers to systems that use 100% of RES, or 100% of waste heat, or 100% of combined waste heat and RES. Thus, as noted by Matkovskyi, an increase in the use of RES and waste heat in the context of full decarbonization of the EU energy system will be accompanied by increased heat accumulation and storage capacities.  

Russia’s attacks on the Ukrainian energy infrastructure have shown that normal energy-generating facilities are very exposed to air attacks. Thus, the transition to distributed generation, including RES, and expansion of heat supply accumulation in DH systems are crucial and timely for the EU and Ukraine, and these processes should be conducted in parallel.  

The integration of heat storage systems into the DH systems has several advantages: 

Energy security: reduce dependence on fossil fuel imports at the expense of higher RES integration, increase resilience and reliability of heat- and power supply for consumers at the expense of smoothing the heat load peaks (morning-evening) and electricity generation surplus (day-night, summer). 

Social and economic advantages: ensure continuity of heat supply, decrease the thermal energy cost for consumers at the expense of improvement of energy efficiency, and additional revenues for heat-generating utilities at the expense of power network balancing.  

Ecological and climate advantages: reduce the emissions of harmful substances, advance decarbonization of heat supply that improves air quality and mitigates climate risks.  

The workshop participants also learned about the main types of heat accumulation systems (presentation by Kyrylo Baranchuk, Technical Support Engineer from Danfoss), the possibility of improving the energy efficiency of DH systems at the expense of heat accumulation (presentation by Ievhen Nikitin, USAID ESP Heat Supply Consultant), specifics of thermocline formation in storage tanks of various configuration (presentation by Hennadii Voropaiev, Director of the Institute of Hydromechanics of the National Academy of Sciences of Ukraine), and the European experience related to solar heat storage in sand (presentation by Staffan Liberteus, GRUNDIR AB).