[Report] Visiting the 'World's Only' LNG·LPG Dual-Fuel Power Plant... All-in-One from Terminal to Power Generation

SK Gas Expands Beyond LPG Sales
Transfers LNG at KET and Generates Power at Ulsan GPS
Completing the Power Value Chain with a Triangular Formation

On a 300,000㎡ site adjacent to the sea near Ulsan New Port, large-scale facilities for transferring and storing Liquefied Natural Gas (LNG) are densely established. About 10 km from downtown Ulsan, if you drive about 20 minutes inland from here, you will find a power plant that generates electricity using the LNG just confirmed. These two facilities are connected by a winding 7 km-long pipeline, allowing the entire process from LNG unloading to power generation to be handled seamlessly.

The first facility facing the Ulsan sea is the 'Korea Energy Terminal (KET),' jointly constructed by SK Gas and Korea Oil & Gas. The second facility, located relatively inland, is the 1.2GW LNG·LPG combined 'Ulsan Gas Power Solution (Ulsan GPS)' power plant, which matches the capacity of one nuclear reactor. SK Gas has grown over 40 years since 1985 with a single business model focused on Liquefied Petroleum Gas (LPG), and in line with the eco-friendly trend, it completed LNG-related facilities one after another last year and officially launched its LNG business this year.

The scene of constructing LNG storage tank number 3 inside 'Korea Energy Terminal' in Nam-gu, Ulsan, visited on the 25th. Korea Energy Terminal, jointly built by SK Gas and Korea National Oil Corporation, currently has two tanks and aims to build up to six tanks, including the SK Gas site behind Korea Energy Terminal. 2025.03.25. Photo by Oh Ji-eun

During a visit to Nam-gu, Ulsan on the 25th, the LNG·LPG integrated value chain completed by SK Gas could be seen firsthand. The first place visited was the construction site of LNG storage tank number 3 within the Korea Energy Terminal. The diameter of the cylindrical LNG tank’s bottom surface is 90.6 meters, which is even wider than Jangchung Gymnasium in Jung-gu, Seoul (diameter 80 m). Once the tank is completed, this large space will be filled with LNG, which remains in liquid form only below minus 162 degrees Celsius. One tank handles an annual LNG volume of 1.2 million tons, enough to cover about 50% of Ulsan city’s city gas demand.

SK Gas has created a power business structure that connects import, storage, supply, power generation, and sales by leading a 'triangular formation.' In addition to the 'SK Gas Ulsan Base,' which was introduced in 1989 and can store 270,000 tons of LNG, the 'Korea Energy Terminal,' completed last November, is responsible for LNG unloading and transmission. Ulsan GPS began commercial operation in December last year, generating 1.2GW capacity by sourcing LPG and LNG from these two facilities.

Unlike LPG, LNG emits fewer harmful substances, making it an eco-friendly fuel. However, it is highly affected by weather and supply conditions, causing significant price volatility during international issues. The company states that it has diversified its power portfolio to better respond to price volatility. When LNG costs are high, it can supply power using the LPG facilities it previously owned. Transportation is also convenient. Ulsan GPS is connected by a 3 km pipeline from SK Gas Ulsan Base and a 7 km pipeline to the Korea Energy Terminal.

When supplying LNG to customers from the Korea Energy Terminal, seawater at mild temperatures is used to vaporize LNG in an eco-friendly way. LNG, which is liquefied at temperatures below minus 162 degrees Celsius, must be converted into gaseous natural gas (NG), and this process minimizes environmental impact by not generating additional heat. The company is continuously researching ways to reuse the 'cold energy' generated during this process.

On the 25th, when opening the window to observe the LNG vaporization process at Korea Energy Terminal in Nam-gu, Ulsan, seawater was continuously falling from a height of several tens of meters. Korea Energy Terminal uses about 10,000 tons of seawater to produce approximately 180 tons of NG. 2025.03.25. Photo by O Ji-eun

Opening a window to observe the vaporization process, seawater was seen falling continuously from a height of several tens of meters. The Korea Energy Terminal uses 10,000 tons of seawater to produce about 180 tons of NG. The more large-scale seawater circulation there is, the less the temperature change in the sea, so a large amount of seawater is used. LNG flows through wide, flat pipes shaped like rectangular plates with winding paths, and seawater flows along these pipes to convert LNG into NG. The reason for using wide, flat pipes is to increase the surface area for better heat conduction. The converted NG flows along the upper pipes toward the demand sites.

Ulsan GPS is the world’s first LPG·LNG combined gas combined cycle power plant, with SK Gas holding a 99.5% stake. SK Gas has designated this year, when LNG production is being actively expanded at Ulsan GPS, as the first year of LNG business expansion. Ulsan GPS’s location inside the Ulsan industrial complex is considered its greatest advantage due to excellent site conditions. The Ulsan GPS combustion system uses two Siemens latest 410.5 MW gas turbines and one 406 MW steam turbine. Since both LPG and LNG are used, Siemens specially manufactured turbines capable of burning both fuels.

On the 25th, a panoramic view of Ulsan GPS located in Nam-gu, Ulsan. On the left, two towering devices are the latest Siemens gas turbines. 2025.03.25. Photo by Oh Ji-eun

Based on its experience with LNG blending, SK Gas announced plans to diversify energy sources to simultaneously supply hydrogen and ammonia in the future.