VANCOUVER - BC Ferries has awarded contracts for the construction of four more energy-efficient "Island Class" ferries, which will join the two that are scheduled to enter service next year.

Damen Shipyards Group, of the Netherlands, will build the ships, BC Ferries said in a news release Wednesday. The Dutch company also built the first two vessels.

As part of the contract, Damen will continue to work with Victoria-based Point Hope Shipyards, which will provide local technical and warranty support for the new vessels. The total budget for the project is roughly $200 million, according to BC Ferries.

Island Class ferries are designed to be completely battery powered, but current charging technology is not sufficient to make electricity available in the quantities required to operate them, the ferry company said.

Once charging technology matures, the vessels will be operated on electricity only. Until then, they will be run as diesel hybrids.

The first two Island Class vessels have completed sea trials and are scheduled for delivery to Victoria in January. They are scheduled to begin operation on the Powell River-Texada Island and Port McNeill-Alert Bay-Sointula Island routes by the middle of next year.

BC Ferries has previously said that Island Class vessels are designed to serve small routes between Vancouver Island and surrounding communities.

The next four vessels in the class are slated for use on the Campbell River-Quadra Island and Nanaimo Harbour-Gabriola Island routes - with two ships on each route - by 2022.

In each case, the two Island Class vessels will be replacing one larger ship, meaning more frequent service and increased passenger capacity per hour, according to BC Ferries.

Island Class ferries have the capacity to carry at least 47 vehicles and up to 450 passengers and crew, depending on their configuration.

BC Ferries said it issued a request for expressions of interest for this project in July 2018, pitching the project to Canadian shipbuilders as well as international ones. A total of 18 international shipyards expressed interest, and nine were short-listed and asked to submit a proposal. No Canadian companies submitted a bid.