The power plant will be built in Amamapare, PT Freeport Indonesia's port and processing site in Papua, with the electricity fed to the Grasberg mine via a 100-km transmission line. Grasberg is located in the remote highlands of the Sudirman Mountain Range and has no grid access.

Wärtsilä will partner with Indonesian Construction engineering company PP (Pembangunan Perumahan) on the project, which will require 14 of Wärtsilä's 34DF dual-fuel generating sets. Financial details of the deal were not disclosed.

"We have completed open pit mining at the Grasberg minerals district, and are now developing large-scale, high-grade underground mines. For this it is critical that we have a reliable and efficient energy supply, and the Wärtsilä generating sets will deliver the power we need," said George Baninni, executive vice president, Freeport Indonesia.

Kari Punnonen, energy business director, Australasia, Wärtsilä said his company had offered the most competitive total lifecycle cost, but that local experience also was a contributing factor.

"This cost was ultimately the deciding factor in the award of this valuable contract. However, we have power plants operating in the vicinity of this site, which provided important references as part of the decision process".

"Our local presence in Indonesia is strong, with 5.3 GW of installed base and 350 employees on the spot. We are able to provide a high level of support."

Wärtsilä added in its statement that the 34DF engines can also operate on a variety of fuels, for instance natural gas. Initially, the engines will run on Indonesian B30 biodiesel. The engines can also integrate energy from renewable sources.

The Wärtsilä equipment is scheduled for delivery between July and November 2021. The first seven engines are expected to be officially handed over in March 2022, with the remaining seven to be handed over in July 2022.