Peaking power can come from a variety of sources, like open cycle gas, traditional or pumped hydro and it has an extremely important role to play in an energy mix as it can be switched on to bolster energy supply when customers need it.

In this context, our new peaking gas plant currently under construction, AGL’s Barker Inlet Power Station, has an important role to play in delivering an energy mix which meets community needs across the year.

How’s Barker Inlet tracking?

We’re well on the road to completion (pun intended). This week, AGL received the first of 12 engines for the power station.

Construction of the Barker Inlet Power Station is expected to be completed at this end of this year.

Currently, around 200 people are working at the site under the direction of the Principal Contractor Wartsila.

How will the plant work?

The Barker Inlet Power Station will have around 210 MW of capacity which involves the installation of 12 reciprocating engines that can generate approximately 18 MW each from either gas and or liquid fuel. The units are capable of operating at full capacity within five minutes of starting, providing a rapid response to changes in renewable generation supply and demand.

This modern power plant will make a significant contribution to improving energy security in SA. It’s new technology so it’s much more reliable than the ageing plant it will replace. The equipment is also much more efficient, requiring 28% less fuel (therefore 28% less CO2).

Responsive to demand

Barker Inlet Power Station is a peaking gas plant, which means it’s flexible in responding to demand, so it can more reliably match changes in wind generation and do so much more efficiently.

Demand snapshot

There are three categories of demand:

  • Baseload - demand that's there all the time, night and day, this has historically been provided by large gas or coal-fired thermal power stations.
  • Intermediate - additional demand on top of baseload when commercial and industrial users are active, this is now supplemented by renewable energy like wind and solar.
  • Peaking - usually occurs on very hot days when everyone's air-conditioners get turned on at the same time, this is can be met by gas reciprocating engines like Barker Inlet, open cycle gas, or pumped hydro.

What has prompted the increased need for peaking power?

The declining cost of utility (large) scale renewables has spurred its rapid development and so there is a greater need for highly flexible capacity which can be switched on or off according to the more variable needs of the market given renewables aren’t always available.

This increasing need for flexible and dispatchable energy, like gas peaking plants, is why gas is a critical part of an orderly transition to a clean and reliable energy supply.