Indian Railways has two types of diesel locomotives that are among the most powerful in the country: the WDG5 Bheem and the WDG4G GE. The WDG5 Bheem is a 5,500 hp (4,100 kW) locomotive built by Banaras Locomotive Works in collaboration with Electro-Motive Diesel. It is based on the EMD SD80MAC and has a 20-cylinder engine. The WDG4G GE is a 4,500 hp (3,400 kW) locomotive built by GE Transportation and Diesel Locomotive Factory, Marhowrah. It is based on the GE Evolution Series and has a 12-cylinder engine.
Both locomotives have AC-AC transmission and can haul heavy freight trains at 100 km/h (62 mph). However, the WDG4G GE is more fuel-efficient and environmentally friendly than the WDG5 Bheem, as it meets the UIC-1 emission norms and consumes less diesel per km. The WDG4G GE is also more reliable and easier to maintain, as it has fewer moving parts and a longer service life. Therefore, the WDG4G GE is a better choice for Indian Railways than the WDG5 Bheem, which has been discontinued after only 7 units were produced.
