Leading Indian contract mining group Thriveni Earthmovers is one of the largest Mine Developer and Operator (MDO) players in the country and is already noted for its innovative approach to mining. One of the challenges faced by mine operators to move towards green mining practices is the huge capital required to invest in new electric machinery, especially when you are operating diesel powered assets which still have a large residual life left in them.

To overcome this challenge, Thriveni, among the many initiatives being undertaken, decided to convert an existing 900 kW diesel powered excavator of the 250 t class (Hitachi EX2500) to electric operation at a coal mine owned by NTPC where it has the MDO contract. NTPC supported the project along with the state Directorate General Of Mines Safety (DGMS). This was a formidable exercise due to the technical challenges & the importance of maintaining functionality while ensuring safety at the highest level. The company told IM it involved the replacement of the engine with an electric motor, redesign of the internals of the gearbox, modifying the swivel joint to incorporate a slip ring arrangement for power lead-in, as well as installing the required electric control systems and safety provisions. The entire design, development and integration was done by the in-house engineering & technology team at Thriveni.

Much of the components have been designed and developed within India through the excellent vendor base that Thriveni has. The newly electrifed excavator has been put into trial production and has shown performance equivalent to the original diesel unit. The company added that work is now underway to progressively convert all the large excavators in Thriveni’s fleet into electric driven units. The potential is huge – this one excavator has the potential to reduce carbon emissions by as much as 2.7 million kg per annum.