When you think about all the various independent generation types, the millions of kilometres of wires, the sheer size of Australia, the impact of extreme weather events, and the millions of customers switching appliances on at random, it’s amazing the grid works as reliably as it does.
That only happens due to a whole bunch of work, technical analysis, and modelling going on behind the scenes. For example, for the past couple of months the Australian Energy Market Operator (AEMO) and industry have been getting ready for what’s predicted to be an unusually hot summer.
In conjunction with businesses in the energy sector and big industrial energy users, such as Alcoa’s Portland aluminium smelter, AEMO has been preparing our power systems and their operators for a summer of extreme demand.
This includes AEMO offering financial incentives to major industrial power users to cut their use when demand peaks in order to reduce the likelihood of blackouts at a time when many Australians are expected to switch on their air conditioners.
Are you prepared in case your area is subjected to load shedding?
How likely are blackouts this summer?
In its Summer Readiness report, AEMO warns that demand for electricity could spike to a once-in-ten-year high in the coming months.
This has increased the risk that we will see forced power outages across the country.
As a result, AEMO has been seeking contracts for additional supply, particularly in South Australia and Victoria.
“This year’s summer forecast is for hot and dry El Niño conditions, increasing the risk of bushfires and extreme heat,” AEMO’s executive general manager of operations Michael Gatt explained.
Bushfires and extreme weather can damage transmission poles and lines, causing unplanned power outages. If this happens at a time of peak demand, there may be no avoiding selective load shedding, also known as rolling blackouts.
What is load shedding?
Because the national electricity grid needs to stay in balance, with supply matching demand almost perfectly at all times, margins of error are very small.
If it’s clear that there is no possibility of getting enough supply to meet demand at a particular time, demand has to be reduced.
This is when load shedding, the deliberate shutdown of parts of the power network, is required.
This can involve switching off electricity to whole suburbs or directing big industrial users to cut or pare back their usage, and sometimes both.
Load shedding is regarded as an absolute last resort to protect the grid from collapse. This is why South Australia had a statewide blackout in 2016 and 200,000 Victorian consumers and businesses were subjected to rolling blackouts during the last El Nino summer in 2019.
Who decides where load shedding happens?
When AEMO has no option but to call for load shedding, they work with distributors (not retailers, like GloBird) to decide where power will be switched off.
Distributors try to minimise the impact by rotating the disruptions between different areas (rolling blackouts), and prioritising power to major health facilities, emergency services and public transport.
On January 25th, 2019, AEMO had to shed 250 megawatts of demand after Melbourne’s hottest day in five years placed “unanticipated levels of demand” on the grid.
AEMO activated emergency reserves, including preparing to pay some businesses to voluntarily curtail their own usage, but those reserves were not enough to cover the shortfall.
Power was also imported from South Australia, Tasmania, and New South Wales, but more could not be brought in as interconnectors were at their maximum limits.
AEMO later confirmed that more than 200,000 Victorian consumers had been impacted by the load shedding over the course of the day.
Around 50 Melbourne suburbs and regional areas were impacted, including Southbank, Armadale, Toorak, Camberwell, Fairfield, Northcote, Caulfield, Elwood, Beaumaris, Bulleen, Burwood, Riversdale, Epping, Rowville, Cranbourne East, Bentleigh, Balaclava, Malvern, Balwyn, Surrey Hills, Essendon, Glenroy, Broadmeadows, West Footscray, Fairfield, Ivanhoe, Alphington, Airport West, East Keilor, Niddrie, Ascot Vale, and Moonee Ponds.
You can (and probably should) prepare for load shedding
As AEMO has flagged the likelihood of very high demand caused by very hot weather at some stage in the coming months, it’s worth thinking about an “emergency kit” to make sure you’re prepared in case load shedding does happen in your area.
Know where your torch is and make sure that you have batteries for it and maybe also put some candles and matches somewhere they’re easy to get to. Having a battery-operated radio will allow you to monitor the situation if your electricity does go out.
A portable power bank to recharge mobile phones is probably a must have these days.
Speaking of mobile phones, it’s worth considering installing a couple of apps: the BOM weather app, the Red Cross Get Prepared app, and Emergency Plus, developed by emergency services in conjunction with the federal government.
If you have life-support equipment, like an oxygen concentrator or kidney dialysis machine, make sure you register with your energy retailer because, by law, you’re entitled to additional support before and during a power outage.
Who will contact you if load shedding is about to be implemented?
The company responsible for electricity distribution in your area will notify you via SMS if there is a chance that you will be impacted by load shedding over the coming hours. They will usually give you an indication of the potential start and end time of the “Power Response event”.
Electricity distributors must also provide information about the outage via a 24-hour phone number and on their website.
Hopefully, any load shedding will only happen in a particular area for a couple of hours, as the “rolling” concept means that the impact is shared by staggering the areas being shut down.
If you want to read more about load shedding, check out this page on AEMO’s website: Fact sheet: Explaining load shedding.
Meanwhile, spare a thought for those unsung technicians and analysts stressing about keeping the lights on heading into a challenging summer with unknown demand … and if their hard work pays off and we manage to avoid the need for load shedding this summer, remember that it didn’t happen by accident.