With plenty of wind and sun, South Australia has become a forerunner in renewable energy. A high share of renewables needs, however, to be balanced by flexible power generation.
To improve its energy reliability, AGL Energy Limited, one of Australia’s leading integrated energy companies, turned to Wärtsilä for dispatchable power. In addition to reliability, Wärtsilä’s fast-starting high-efficiency reciprocating engines provide superior value to AGL’s portfolio in the changing Australian energy market.
AGL is Australia’s largest private owner and operator of renewable energy assets and the country’s biggest developer of the firming capacity needed to support renewables. Barker Inlet Power Station (BIPS) will play an important role in the utility’s portfolio, as the plant’s main task will be to ensure reliability in the renewable-heavy South Australian power system and to balance the stochastic production of the renewables. The Wärtsilä engine generating sets can reach full output in a matter of minutes, providing the fast-start capability needed to rapidly respond to the fluctuations inherent to solar and wind power.
Being fuel-efficient, the reciprocating
engines at BIPS are both cost-saving
and environmentally sound: the new
power plant requires 28% less fuel than
its predecessor turbine plant and reduces
greenhouse gas emissions by 35-50%.
The engines have low sensitivity to
ambient temperature and can produce full
power, even at 40 degrees Celsius. The
engines’ negligible water consumption
and their low fuel gas pressure create
further operational cost savings.
As a multi-unit plant, BIPS offers high
operational flexibility and high efficiency
also at part load. Even if one of the
twelve engines was unavailable due
to maintenance, greater than 90% of
the plant capacity would still be readily
available. To match load requirements,
any number of engines can be dispatched
and run at high efficiency.
Continuous starts and stops, which
characterise the operating mode of
renewable-balancing generation, do not
affect the maintenance intervals of BIPS’s
reciprocating engines. Their fast startup capability makes the plant optimal
as balancing capacity, but also provides
increased revenue to AGL.
To align the dispatch interval and
settlement interval, Australia’s National
Electricity Market (NEM) will switch into
a five-minute settlement regime in July
2022. The settlement period for the
electricity spot price will then change
from 30 to five minutes. While leading to
a more efficient market, the switch also
enables a more reliable power system,
where investments in fast-response
technologies are encouraged to back
up renewable energy production. The
fast-starting reciprocating engines of the
BIPS are ideally suited for this new market
structure.
BIPS was delivered on an engineering,
procurement and construction (EPC)
basis. The delivery also comes with a
10-year maintenance services agreement.
Safety requirements are high in Australia
and were a top priority at the construction of BIPS. Through close cooperation
between Wärtsilä, its subcontractor and
AGL, the construction project saw record-high safety numbers: over one million
working hours without a single Lost-Time Incident (LTI).
BIPS is the first utility-scale reciprocating
engine power plant in Australia’s National
Electricity Market (NEM). It is also the first
gas-fired generation capacity added to the
NEM in many years. For Wärtsilä, the plant
is an important step on the path towards a
100% renewable energy future.
