A huge spike in renewables has put the electricity grid under critical pressure at a time when mounting weather crises threaten to undermine the resiliency of the energy system.

The Energy Security Board's annual Health of the National Electricity Market report released on Monday stressed the importance of a resilient electricity system following the bushfire tragedy that ravaged the east coast over summer and warned intense weather will become more common.

Kerry Schott is the head of the Energy Security Board. Its future hangs in the balance. Credit:Louie Douvis

"This needs serious attention in the years ahead as further extreme events including fire, flood and high temperatures can be expected ... The particular specifications and cost of equipment able to withstand these conditions must be re-examined," the report says.

"The increased severity of weather events, especially over summer, coincides with an ageing, and hence less dependable, coal generator fleet."