Australia's clean energy experiment

AEMO's Integrated System Plan is its "roadmap". It presents a set of scenarios comprising various assumed mixes of built generation, transmission and storage that could complete the clean energy transition. How, when and where those projects will happen, who manages them and what they'll cost are not given. And no-one appears to be in charge of implementation.

The ISP is not a normal construction plan. It's "a plan for investment in the NEM to ensure a reliable and secure power system through Australia's transition to a net zero economy".

So AEMO's role is to urge investment in renewables and offer investment signals to the market. In other words, with governments foreshadowing closure of fossil fuel generator, the energy market operator is encouraging investors to enable the energy industry to replace them with renewables. Sounds like crowd funding. Is it working? The recent "rocket" comment suggests not.

Which brings me to the question, is an Australian net-zero clean energy future based on the trio solar, wind and storage actually feasible? There was no feasibility study. It was just assumed. The last few years comprise a preliminary experiment that so far suggests the renewables trio is not adequate.

That's precisely the reason why nuclear energy must be added to the means of generating clean energy. Solar and wind are not doing the job.

What improvement would nuclear energy make to the growth rate? The arithmetic is easy. Like coal-fired power stations, nuclear power plants are often built to total capacities of around 1 gigawatt, much like the coal-fired power stations they must replace. Often they comprise several smaller units on the one site. Power engineers decide these things around what's commercially available or feasible and the expected demand.

Annual energy output is a simple function of rated power and capacity factor (fraction of the year when the unit works at rated capacity). A generator with rated output of 1 GW and capacity factor 80% has an annual output of 25 PJ.

As we have seen Australia's total solar/wind output is presently increasing by 35 PJ per annum, well below what energy policy needs. A typical nuclear power plant can supply 25 PJ per annum. That's not far behind what's lost when a coal-fired plant shuts down. The current shortfall facing us is easily made up with nuclear energy.

Cost and construction rates always come up in nuclear energy debates. On cost the current government has a clear position; "everyone knows renewables are cheapest". Both the Federal government and AEMO rely on one main source of cost information for deciding policy, CSIRO's annual GenCost report. This now includes nuclear costings, even though AEMO itself has explicitly rejected nuclear energy.

It has been suggested that GenCost omits extra system costs like new transmission and storage ("firming") in its renewables costings. Conversely others claim that GenCost's nuclear costings are too high. Nuclear is consistently dismissed by Australian politicians on the basis of its cost. The slogan "nuclear too slow, too expensive" caught on about a decade ago and is still influential. Cost debates will no doubt remain vigorous while the relevant evidence is in short supply.

I enjoy recounting my involvement long ago in a peer-reviewed scientific study of nuclear costs (https://www.sciencedirect.com/science/article/abs/pii/S036054421000602X.

Nicholson, Biegler, Brook, Energy, January 2011). We used published technical cost literature from 2000 to 2010; the study is certainly dated. But it remains relevant and of special interest in its conclusion that just 13 years ago we claimed nuclear was the cheapest clean electrical energy technology for Australia, at least under the conditions explained below.