Baseload and dispatchable (electricity) are terms you have no doubt heard mentioned frequently by our politicians, particularly baseload. These two terms are amongst the most important for understanding the electricity debate. They’re at the heart of our energy distribution/generation paradigm shift.
For many of us, our ability to absorb any more electricity talk is nearing full capacity. For a lot of Aussies, it has already become indecipherable white noise, as the debate has descended into a political mirror maze with no apparent exit signs.
One of the reasons we’re switching off (amongst many valid others) is simply because we don’t understand much of the terminology that is being bandied about. In the electricity debate, commentators use terms like baseload, dispatchable power, peak load, intermediate load, grid stability and a litany of other industry-specific terminologies, with no explanation; and these terms are quoted as if they are as common as your average conjunction.
Do we actually need to understand any of these terms? Well…yes. If you want to know what is going on with the future of your electricity supply; if you want to know what the politicians are scheming so you can make an informed assessment, a modicum of understanding of the lingo is required.
Electricity generation and distribution have an enormous glossary of terminology. But we only need a few of these terms to enter the electricity conversation with some confidence.
Our aim here is to strip these terms bare and define them in as simple a manner as possible. Ideally, when you have finished reading this, the next time you hear baseload and dispatchable used in an electricity context, you will have a working knowledge of their meaning.
Baseload electricity is the constant, invariable quantity of electricity generated to the grid to meet minimum electricity demands over a period of time. That’s pretty well it in a nutshell. In Australia, coal-fired power stations provide baseload electricity. The exceptions are South Australia and Tasmania.
Baseload power comes from large, centralised, mostly coal-fired power stations, and is always being generated, 24/7. The only time it’s not, is when a power plant breaks down or is in scheduled maintenance.
Baseload power is the traditional method of providing Australians with their electricity, and our electrical grid was designed to distribute baseload power. Traditionally, baseload power has been the most reliable and cost-effective method of power generation in Australia. This is changing rapidly, however.
A baseload coal-fired power plant does not have the flexibility to change its output easily or quickly. They are indeed very slow to start up or alter, are unable to adjust down and they take a long time to increase output. This is not satisfactory because the grid needs to be supplied with the appropriate amount of electricity more or less instantly.
A baseload power plant cannot turn its power down in periods of low demand or turn its power up in periods of high demand. This creates a situation of either excess electricity or not enough electricity.
Baseload provides an invariable constant supply. However, electricity demand is not constant, it has peaks and lows. For example, early in the morning when we sleep, demand is low. When the nation awakes, demand increases.
While the coal burning baseload power stations cannot adjust to meet peaks in demand or unpredictable spikes in demand, there are other types of power stations that are engaged to meet the increased demand. These power stations can be gas, hydro, diesel, wind, solar or battery. This power is switched on as required, can be adjusted up or down (depending on the source) and is, more less instant. This is called dispatchable electricity.
Dispatchable electricity is electricity that can be supplied on demand. This power can be switched on and off, meeting its demand in seconds. It can be easily adjusted based on grid requirement, i.e. the amount of electricity consumers need.
In Australia, gas, hydro, diesel, wind, solar or battery (and others) are used for dispatchable power. A coal-powered station does not have a dispatchable capacity as it can take many hours and even days for a coal power station to fire up and meet the demand.
Dispatchable electricity operates in conjunction with baseload and is a very important aspect of grid stability or, as the politicians say lately, keeping the lights on. It is called on for a number of reasons; one key reason is to meet peak demand or spikes in demand.
Dispatchable power’s main roles also include clearance of grid congestion, frequency control and other roles. For the purposes of keeping things simple in this article, we won’t go into the details of these functions.
Dispatchable and baseload in short
- Baseload electricity is in constant supply, meeting the minimum requirements of the grid. Traditionally, it is generated from large, centralised, fossil fuel (coal) power stations. It is inflexible and cannot be varied quickly or easily.
- Dispatchable power is switched on and off to meet electricity demands and variations that baseload cannot satisfy. The generation source varies, and these dispatchable electricity sources are becoming more and more decentralised. They are instant, meaning turning on a dispatchable power plant is like turning a light switch on and off.
Why is there a huge debate about baseload vs. dispatchable?
Our electricity grid is changing, and it’s changing rapidly. The need to radically reduce carbon emissions, coupled with advancing electricity generation technology, is seeing a power evolution that will relegate the old fossil fuel baseload electricity paradigm.
In simple terms, the electricity generation industry, generally accepts that things are changing, and accepts that we are moving irreversibly toward renewable, decentralised power generation.
Even those generators and retailers that survive and grow on baseload fossil fuel power, state openly that this method and its respective technologies have had their day. It is time to focus on dispatchable power generation, with renewables providing the ‘new look’ baseload.
However, some people are resistant to this change. There are those who are telling us renewables cannot provide the reliable power we need, and that only coal-driven baseload power will “keep the lights on.”
Currently, the most significant voice for maintaining the coal-driven baseload system is the Australian Federal coalition government. They are using whatever methods they can to convince Australians of their position.
Now you have a new understanding of what baseload and dispatchable actually mean relative to electricity generation and distribution.
While this new information may not inspire you to re-engage with the electricity argument, you will at least be familiar with some critical language when you hear it.
Persisting with fossil fuel baseload electricity is a little like insisting we use Morse code on the telegraph while keeping a smartphone in our back pocket.
Baseload and dispatchable power as we understand it now is changing. The resistance to this change coming from our leadership is very difficult to fathom. The change is inevitable, it’s upon us already, but is not without significant challenge.
However, it would be a lot easier for everybody concerned if the top echelons of our policymakers would embrace the future, instead of demonising real progress while propping up our grandparents’ technology and telling us (falsely) it’s for our own good.
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