"The base load on a grid is the minimum level of demand on an electrical grid over a span of time, for example, one week. Base load power sources are power stations which can economically generate the electrical power needed to satisfy this minimum demand."So base load power stations are those that produce power cheaply at a steady, or near steady, rate. Coal and nuclear power stations, which are unable to quickly, easily and efficiently change their output to fit the variation in the demand on the power grid, are well suited to provide base load power.
With the rise of renewable energy there will be less and less need for
base load power and more and more need for peaking power.
Hydro power is not base load, it is available as required within the limits set by long-term rainfall.
Pumped hydro is not base load, it is readily available energy storage suited for storing large amounts of energy. Its availability is not limited by rainfall because it uses the same water over and over again.
Batteries do not provide base load, they also provide readily available energy storage, available at even shorter notice than pumped hydro. As of the time of writing, 2017, batteries cannot store the large amounts of energy that pumped hydro can. Batteries can also provide valuable grid services.
Solar thermal is not base load; it provides energy as required within the limits of available sunshine. It typically has several hours storage.
Obviously wind power and solar PV do not provide base load power.
The Liddell power station closure is not scheduled until 2022. This is five years off at the time of writing. In this time the Australian power supply mix will change greatly and the need for base load power will decline substantially. In these five years:
On current trends Australia will have far more renewable power five years in the future than it does in 2017. Much of this power will be available only when the wind blows or the light is bright (direct sunlight is not needed for solar PV power generation).
There will be a strong need for peaking power to fill the gaps when the renewables are not generating sufficiently to fill the demand. (In the longer term energy storage, most economically pumped hydro, will fill much more of this need.)
Diesel is easily and cheaply stored for long periods. Diesel powered generators, that will only be needed a small percentage of the time, will be ideal for the needed rare peaking power in exceptionally high demand times in the short- to medium-term. South Australia is planning to use diesel generators to fill this need for peak demand in the summers of 2017/18 and 2018/19.
On this siteHow should Australia generate its electricity?
South Australia's success with renewable power
Mid-North South Australia, leading the nation in renewable energy
Northern SA's renewables
Wind power in Australia
Impressive renewable energy developments in Australia
Pumped hydro power
Glossary of technical terms relating to wind power
Climate change disasters and the Australian government's actions
Greatest crime in history
Major threatened disasters compared
The end of coal
Coal seam gas: an environmental disaster
The Turnbull Australian Government
On the InternetA glossary of the energy debate; The Conversation.
Renew Economy; AGL ridicules Coalition request to keep Liddell [coal-fired power station] open extra 5 years.
The Conversation; Why coal-fired power stations need to shut on health grounds.
More coal doesn't equal more peak power, Alan Pears, The Conversation, 2017/09/13.
The big three Australian power generators see no future in coalAGL's statement on the Liddell closure.
Energy Australia boss says there are much better options than keeping the old Liddell coal-fired power station running for a few more years.
Origin Energy boss regects coal