10/02/2017 7:19 AM AEDT | Updated 10/02/2017 2:57 PM AEDT

The Heatwave Is Coming, And It May Cause More Blackouts In SA And NSW

A warning has been issued, as senators prepare to bring the heat too.

As temperatures soar across the country this weekend, South Australia and New South Wales may be battling more than just the heat with possible power outages flagged across both states.

The two states will battle temperatures warmer than 40 degrees on Friday and the Australian Energy Market Operator has warned the hot weather may lead to blackouts.

In a statement released on Thursday afternoon, the AEMO said an increasing electricity consumption on the sweltering days may place "additional strain on the national power system" and a market notice has been released to notify generators of a "forecast potential shortfall" in NSW from 5.30pm on Friday.

The AEMO is discussing the need for local load shedding to deal with the increased electricity demands across NSW in particular. Load shedding is essentially the AEMO telling power companies to switch off customers' power supply.

This occurs when the power system's supply and demand is not in balance, putting the system at risk.

On Wednesday, about 40,000 properties in South Australia suffered power outages as the state battled one of its hottest days. Load shedding was ordered by the AEMO, a move which was criticised by state politicians including the South Australia Energy Minister Tom Kountsantonis.

South Australia has suffered a number of power outages over the past few months, with an outage sweeping the entire state in September.

The issue is different in South Australia as a large proportion of power generation comes from intermittent renewable energy sources like wind and solar. When wind doesn't blow, power is limited from wind farms. The state's biggest coal-fired power plant was also closed last year.

A report released by the AEMO in December revealed South Australia's renewable-heavy power supply did play a factor in the statewide blackout.

The federal government has criticised the state's power plan, with critics including Prime Minister Malcolm Turnbull calling for more diverse sources of power to be readily available on demand when there is overwhelming electricity consumption.

Federal energy minister Josh Frydenberg has asked the AEMO for a report into South Australia's power outages on Wednesday after the regulator and state government disagreed on the need for load shedding.

An inquiry into the resilience of electricity infrastructure is being held in Canberra on Friday, where senators will question representatives from renewable energy agencies and the AEMO.