Diesel Generators at Morwell by Dan Caffrey


(photo: Brett Tippet)

Over a hundred diesel generators are in the process of being placed on the site of the old Briquette Factory at Morwell, (decommissioned in 2009), in order to provide back-up electricity supply on the really hot, high demand days of the coming summer. Despite our local Latrobe City Councillors trying to make a big deal of this when the Minister overrode their discretion to object, it really is not something to be too concerned about for the following reasons.

1. The probability of them not ever being turned on is 61%

2. The probability of them being run for a maximum of 8 hours in the three months they will be there is just 32% and the probability of them being run for longer than 20 hours is almost zero. These probabilities were calculated on an analysis of the likely weather conditions, the existing generating capacity and other measures to abate demand on extreme weather days

3. AEMO made the decision to install the generators here, based on the scientific imperative

4. It is only ever intended to run these generators as the very last resort and a lot of things would have to go wrong before this happens

5. The siting at Morwell as opposed to at Hazelwood is because it is right near the lower voltage – 22 kV power lines that used to connect the briquette factory. The Hazelwood power lines carried loads of up to 660 kV, which would be unsuitable for the 102 MW output of the combined generation capacity for these diesel generators.

6. If the generators were activated, it would be when north winds were blowing and would take the noise, exhaust fumes and particulate matter away from the Morwell township and in any case the amount of pollution would be less than any of the coal fired power stations, notwithstanding that the pollution is exhausted from stacks at almost ground level compared with the 100 metre stacks of a power station

7. Extreme demand only ever lasts for spikes of at most 3 hours.

8. The hierarchy of events to respond to higher demand on extreme weather days is  a) Power up the coal fired plants to maximum capacity b) Increase the amount of hydro power c) Fire up the existing gas fired peaker units that exist around the state d) Import power from Tasmania via Basslink and the other states by one of the inter-connectors e) Demand Damping, whereby customers voluntarily agree to reduce their demand and get rewarded financially for doing so.

The important thing to remember is that these generators are a transitional arrangement and are only potentially needed because there is not enough dispatchable power in the system; things such as pumped hydro and solar thermal power stations with storage. These facilities are being built now and should ease the situation next summer and progressively more so over the years as more renewable energy comes online over a wider area of the country. This will ensure that the electricity grid is more constantly supplied with those very useful electrons.