Wärtsilä was awarded a power plant contract for an 85 MW replacement, and extension of an existing diesel power plant at Manisa in Western Turkey. It involved the very first three Wärtsilä 50DF generating sets for a power plant installation, delivered in 2004. Four Wärtsilä 34SG sets were added in an extension in 2005.
The new engines replaced three Wärtsilä 18V46 diesel generating sets running on light fuel oil. The new plant allowed changing fuels from oil to natural gas. It was supplied under an engineering, procurement and construction (EPC) contract.
The power plant serves the Manisa Organised Industrial District (MOSB), one of Turkey’s largest business centres. The MOSB houses industrial companies from paper, electronics, furniture and chemicals to food and textiles.
The plant has a high overall efficiency and is very flexible in operation. High energy efficiency is due to the use of waste heat recovery to supply hot water and steam to the industrial park. The total steam production capacity is around 40 tonnes/h at a pressure of 14 bars. Hot water is fed into the district heating system of the industrial park, with the heating network pipeline of 6 km.
The generators deliver electricity to the local grid of the industrial park through 34.5 kV transformers. Excess electricity is sold to the public grid at a price determined by the Turkish electricity authority.
Flexibility is given by the use of two sizes of generating sets, and the dual-fuel capability of the 50DF generating sets. Whereas the previous engines burned heavy fuel oil, the new engines are running on natural gas which is piped to the site. The Wärtsilä 50DF can switch over to fuel oil in case of an interruption in the gas supply. The Wärtsilä 34SG engines are pure gas engines.
When the engines are running on natural gas, the plant is able to meet the environmental regulations without using the deSOx system that was installed with the original heavy fuel-burning engines for removing sulphur oxides from the exhaust gases. The dual-fuel engines bypass the deSOx system when they are burning natural gas. If the operator wants to switch the 50DF engines to heavy fuel oil the deSOx is put back into operation.
The installation of the plant required careful organisation. The previous generating sets were replaced within a time span of seven months. However, it was necessary to exchange the sets while keeping two sets running at all times. The Wärtsilä 18V50DF generating were delivered in September 2004 and the Wärtsilä 34SG sets were delivered in January 2005. The construction time of the power plant extension was eight months.
