Power plant - Cheong Soo - South Korea
Cheong Soo + Wärtsilä

Reference case

Introducing trigeneration in Cheong Soo

In May 2007, Wärtsilä was awarded a contract from JB Enertek Co., Ltd., South Korea, to deliver engineering and equipment (EEQ) in two phases for a 25.3 MWe combined heat and power plant (CHP).

The plant is located in Cheong Soo community in Cheon Ahn City, approximately 100 kilometres south of Seoul, Korea. The purpose of the Cheong Soo trigeneration plant is to provide district heating and electricity to a suburban area covering approximately three square kilometres with about 6400 households and public buildings. The first phase of the project comprised two Wärtsilä 20V34SG natural gas-fuelled generating sets equipped with a heat recovery system for district heating purposes. Phase 1 was commissioned and handed over in February 2010. The second phase consists of an identical genset to the previous and is scheduled to be completed in 2015. The three gensets generate electricity in parallel with the electrical grid and supply district heating to the town network.

During the warm summer periods the plant provides district cooling as well. Due to tariff policy in South Korea, selling only electrical power to the grid is not feasible. At night, the electrical load in the suburban area is so low that the amount of heat generated by the engines at this time is significantly reduced compared to daytime. Unfortunately, the amount of heat needed by households during this period of time in the 24-hour cycle is at its maximum. This is why installing a heat accumulator comes into question: it allows the Cheong Soo plant – operating essentially in island mode – to run continuously on high load and thus, at high levels of total efficiency (more than 85% in this case). The additional heat generated during daytime is partly stored in the accumulator for use during the following night.

This was the first CHP project delivered by Wärtsilä in South Korea under the CES (Community Energy System) concept which is based on South Korean legislation to encourage decentralized energy production. The objective of the CES concept is to supply electricity and heat from independent power production facilities to commercial, residential, business and hospital buildings in specific areas.

After the completion of the second phase, the total electrical output of the plant will be raised to 25 MWe and thermal output to 21 MWth. Wärtsilä designs, procures and delivers the equipment as well as provides technical advisory services at site during the installation and commissioning works. The erection and installation of the equipment is carried out by JB Enertek and local contractors.

WhoJB Enertek Co., Ltd
What 2 x Wärtsilä 20V34SG & 1 x Wärtsilä 20V34SG Flexible Baseload
WhereCheong Soo, South Korea
HowEEQ (Engineered equipment delivery)

This is what we achieved


MW of electrical output


MW of district heating output


Total operating efficiency

Cheong Soo CHP is the most successful engine plant in South Korea and we are very proud to supply power and heat to our customer by using Wärtsilä 20V34SG engines.

Mr DP Lee, Gas Equipment 1 Team, Sales Manager, JB Enertek Co., Ltd.

How we did it

Challenge icon


  • Electrical load minimal but head demand maximum at night
  • Electricity generation parallel to the grid
  • Meeting the noise level and emission requirements set by Korean legislation
Solution icon


  • Charging of heat accumulators during daytime and consumption of heat at night
  • Wärtsilä 34SG gensets provide continuous and reliable energy
  • Advanced emissions and noise reduction equipment were installed
Benefit icon


  • Minimum 85% efficiency 24 hours a day
  • Avoiding the costs of installing external site connections 
  • Compliance with regulations allows plant to operate efficiently and avoid potential penalties

The main details

   Customer  JB Enertek Co., Ltd (IPP)
   Type  Wärtsilä 34SG gas trigeneration power plant
   Operating mode  Flexible baseload
   Gensets  2 x Wärtsilä 20V34SG & 1 x Wärtsilä 20V34SG
   Total output  25 MWe + 21 MWth 
   Fuel  Natural gas
   Scope  EEQ (Engineered Equipment Delivery)
   Delivered  2010 & 2015
Cheongsoo map

Would you like to know more?

Contact us

Contact us

Fill in a contact form and our experts aim to be in contact within 1-2 business days. Contact us »


Read our brochure

Read our product brochure to get all the details.


Find your local office

Find a Wärtsilä office near you.

Related solutions and services

Related materials

Trusted partner to the best companies in the world

swb Bremen CHP power plant
Bremen, Germany
Wärtsilä and Uniper enable a revenue-adding transition from coal to gas for public utility swb Erzeugung in Bremen, Germany. When...
Pesanggaran - Bali
PLTD Pesanggaran, Bali
Grid stability in Indonesia – 200MW multi-fuel power plant generating reliable electricity in Bali with operational and fuel...
Makuhari Power Plant, Japan
Makuhari, Japan
The growing demand for natural gas as fuel and the increasing importance of environmental values in Japan have encouraged...

Related press releases

Wärtsilä Energy. Let's connect.