Good Practice: Energy Efficiency in District Heating Pleven, Bulgaria

Download the Good Practice Case Study (174 Kb PDF)

Setting

Country: Bulgaria
Location: Pleven
Project start date: 2007
Project end date: February 2008
Technology keywords: Combined Heat and Power, District Heating
Host sector: District Heating Company
Ref: SETatWork Good Practice # 28

Objective of the Project

To carry out a renovation of district heating station implementing a CHP unit based on a gas turbine.

Technical Summary

The project was executed in DHC Pleven, Bulgaria. It included instillation of a gas turbine and boiler-utilisator, after which the produced steam is fed to the existing main steam collector and feeds the respective steam turbine. A heat exchanger is installed at the outlet of the bolier-utilisator to utilize the heat of exhaust gases using water as a heat carrier. The overall capacity of the unit is 108 MW of which 32 MW electrical capacity.

The overall efficiency of the cycle is 84 % while only the electrical efficiency is max. 38 % depending on the workload of the turbine, the working regime and the ambient temperature.

Technical data of the gas-turbine LM - 2500+ are given below:

1. Electrical capacity - 32 056 kW_el.
2. Natural gas consumption - 9 670 kJ/kW_h
3. NOx emissions < 51 mg/Nm³ at 15% O₂
4. CO emissions < 31 mg/Nm³ at 15% O₂
5. Capacity of the heat exchanger:
• without additional burners - 10.4 MW
• with additional burners - 9.8 MW
6. Total cycle efficiency:
• without additional burners - 84.15%
• with additional burners - 88.26%

Project results:

Annual production of 227000 MWh electricity and 381000 MWh heat energy in the new installation;

Project benefits include:

• Combined heat and power production with high overall efficiency;
• Production of energy based on natural gas fuels with low emission factor;
• Greenhouse gas emission reductions.

The generated electricity is fed to the national grid at 110 kV and the generated heat to the consumers of Pleven town, respectively steam for industrial consumers and hot water for space heating and domestic hot water.

Lessons learned and conclusions:

This type of equipment for combined heat and power based on gas turbine is very appropriate in cases of consumption of both steam for industrial purposes and hot water for space heating and domestic hot water preparation. The industrial steam consumption ensures better capacity utilization of the CHP unit.

The cycle has high overall efficiency over 80 % and is very suitable for replication in DH stations where there is all-year-round consumption of heat.

See the Good Practice Case Study PDF file for further information

Environmental and Social Benefits

(Estimate of) Greenhouse Gases abated (in metric tons of CO₂-equivalent):
Annual: 154 000 tCO₂-equivalent in average. Up to and including 2012: 770 000 tCO₂-equivalent. Up to a period of 10 years: 1 540 000 tCO₂-equivalent. Up to a period of 15 years: 2 310 000 tCO₂-equivalent

Economic Data

Capital Costs: 37 million leva

To find similar reports, click on a keyword below:
SETatWork: Sustainable Energy Technology at Work (2008-2010) : Combined Heat and Power : Engines, Turbines and Transmission : Heat Generation, Recovery and Use : Industrial Combined Heat and Power : Power Generation and Use

Toplofikacia Pleven