Prime mover with more power, less exhaust emissions while maintaining high efficiency for electricity power generation on heavy fuel oil.

Wärtsilä Corporation today introduced the new 20-cylinder 46F engine for power plant installations burning heavy fuel oil. The new engine develops 23,000 kW at 600 rpm, suitable for both 50 and 60 Hz electricity generation. It offers more power and less emissions than the existing 18-cylinder Wärtsilä 46 engine, while maintaining the high energy efficiency. Therefore the Wärtsilä 20V46F offers more value for money with lower lifecycle costs.

The new Wärtsilä 20V46F engine develops 1150 kW/cylinder compared with 975 kW/cylinder from the Wärtsilä 18V46, at 600 rpm (50/60 Hz) as opposed to 500 rpm (50 Hz) and 514 rpm (60 Hz) respectively.

The Wärtsilä 46F is especially environmentally friendly. It has low NOx emissions, down to 710 ppm NOx at 15% oxygen, which is the required level in India today. The Wärtsilä 20V46F will also be able to comply with the World Bank environmental requirements, which are becoming increasingly stringent. However, as it is a known fact that reducing NOx emissions has an adverse impact on fuel consumption, the Wärtsilä 20V46F incorporates design features which enable optimizing the fuel consumption while meeting the required NOx emission levels. Additionally, the engine can minimize the fuel consumption adaptively according to prevailing ambient conditions.

Though visually similar to the original Wärtsilä 46 launched in 1987, the new Wärtsilä 20V46F engine is packed with new features including twin injection pump and scaleable control, for high performance and low exhaust emissions, regardless of fuel quality. It is ideally suited to applications which place a premium on savings in operating and maintenance costs, superior environmental performance and fuel adaptability.

The complete Wärtsilä 20V46F diesel generating set measures 21 m long with an extreme width of 6.275 m and height of 6.2 m above the underside of the baseframe, and has a total weight of 413 tonnes. It is designed to be dismantled to three discrete units, namely the engine with baseframe, generator with baseframe, and the turbocharger module, for separate transport to site. The separate elements are designed for easy assembly on site with minimum installation time. The largest unit is the engine unit, which weighs less than 300 tonnes, conveniently enabling transportation with a heavy lift ship.

The Wärtsilä 46F engine was initially introduced for marine applications in 2004 when a six-cylinder engine began running on the test bed in Vaasa. The first Wärtsilä 46F marine engines entered service at the beginning of 2007 and the longest-running engines have some 3100 running hours. To date 14 marine engines have been delivered. The 20-cylinder Wärtsilä 46F launched today began running on the Vaasa test bed in November 2006, and has accumulated 1250 hours of test running.

The Wärtsilä 20V46F is targeted at those power plant markets which today still employ liquid fuels and require new, higher output generating plants with lower lifecycle costs and less emissions. Despite the focus of many power plant markets being on gaseous fuels, there are many strong markets such as many islands world-wide, Brazilian hydro power backup plants and African baseload plants, where only liquid-fuel operation is possible and heavy fuel oils are used for operating economy.

Manufacture of the Wärtsilä 20V46F engine will be undertaken in Wärtsilä's Delivery Centre in Trieste, Italy. The first engines are expected to be shipped in the later part of 2009.