Project Information

A tour group at inspecting one of the DUPS at a community open day in October 2012
A tour group at inspecting one of the DUPS at a community open day in October 2012


One of the most exciting prospects in KIREIP and a world first in this application is the Uninterruptible Power Supply class Diesel engine or D-UPS.

KIREIP is aiming to enhance the value of existing renewable energy generation on King Island. The way which this can be done is to switch all diesel generators off during periods where there is plenty of renewable generation.

When renewable energy generation solely meets the customer demand, it results in what is called 100% renewable energy penetration. The first time this is achieved it will be a world first for an off-grid system of this size.

Each D-UPS unit contains a large mass flywheel, which uses excess wind energy rather than diesel power to maintain its motion. Its diesel engine operates only rarely when the unit is required to provide power for an extended period, otherwise the mass of the flywheel carries sufficient energy to cover the gap in power generation.

Although D-UPS is a well-proven commercial technology, common in airports and data centres, the application of these units in a remote power system of this size is a world first.

In the King Island system the D-UPS allows all primary diesel generators to be switched off, when there is a period where renewable energy generation is greater than the customer demand, resulting in what is called 100 per cent renewable energy penetration.

Without the D-UPS, switching diesel units completely off would present a problem.

If the wind generation were to reduce quickly the primary diesel generators would not be able to be switched back on fast enough – resulting in a gap in power generation and a blackout.

This is where the D-UPS comes in.

So how does the D-UPS work?

The D-UPS provides an immediate short-term backup for the primary diesel generators – it makes sure that there is not a gap in generation when the customer demand rapidly exceeds renewable generation.

The flywheel of the D-UPS contains significant inertia and if renewable generation drops, the inertia of the flywheel can quickly start the attached secondary diesel generator. The D-UPS unit can cover the gap for enough time to allow a larger primary diesel engine to be started.

The D-UPS provides the system operator with the confidence to switch off the primary diesels knowing that they have the short-term backup required under all circumstances.

The completion of the D-UPS is a huge step in the King Island renewable energy journey allowing the island to have periods where it is powered by 100 per cent renewable energy.