Blackouts !

There is growing concern that we may lack sufficient power generating capacity to avoid load shedding - and the inevitable blackouts that will cause - in summer demand peaks unless Liddell power station remains on the grid past 2020.  Present plans call for it to close by that date.

Last week we had a major bushfire in Sydney's south-west and it seems that came perilously close to causing a major blackout city wide.  That would have  been a disaster.  The trains would have stopped, isolating people and shutting down commerce.  The lack of traffic lights would have created chaos on the roads and the entire hospital system would have had to depend on generators to keep life preserving equipment running.

Sadly, there is a strong suspicion that fire was deliberately lit.   It roared through the bush that makes this city such a delightful place to live and threatened the 330-kilovolt transmission lines that bring electricity into the city.  We were only saved because transmission engineers managed to juggle the load by reducing distribution and they freely admit that luck played a major part.

While this fire did not burn down the transmission lines, the heat raised the air temperature around the wires, making it harder for them to transmit power.  At the same time soot and ash settled on the lines, causing micro arcing and bringing the system close to closing down to prevent lasting damage. Once the system trips and shuts down, restarting is a delicate and lengthy process - and this fire persisted for several days.

It is said that trees are the " lungs of the city " and we guard them carefully, but there must be a degree of logic in the way they are balanced.  The ground under high voltage transmission lines is kept completely bare as a fire precaution, but this fire made it obvious that this is insufficient.  The forest on each side of that bare strip needs further thinning and it should have high priority for remedial burning to reduce the fuel load.

Last summer broke a lot of temperature records and it seems that the hot part of the year starts earlier and last many weeks longer.  As a consequence, we face a longer bushfire season and we need to plan fire safety accordingly.  What was sufficient in the past will not meet our needs in the future.

We need a comprehensive plan to manage the dense stands of bush that still separate suburbs.  Our fire fighting services know where fire breaks will enable them to isolate fires and stop them roaring unchecked into suburban housing and they need legislation to make that happen.  Such a plan will not be popular with some sections of the public, but we saw what can happen in both Hobart and Canberra several decades ago and fire danger has since increased.

Perhaps last weeks fire was a timely warning.  Whether we believe in global warming or not, fire is delivering a greater danger each summer and we had better re-plan our defences.  If we fail to do that, we will pay a price in lost homes - and lost lives !