A few days ago Rafe posted about the proposed solar farm “near Tennant Creek” that will send electricity to Singapore via a “Bass link” on steroids. The numbers are impressive. The solar array will be rated at 10GW, which is 10,000 Megawatts or around one third of the average Australian peak load. Because it is a solar installation and produces nothing for half the year there will be storage and this will also be on steroids, 22GWh or 22,000MWh. By comparison, SA’s “Big Battery” is rated at 100MWh so the one proposed 220 times larger.
One of the proponents makes the masterful understatement that: “It’s a huge project on a world scale, right? This is not big just on Australian scale. This is big on a world scale…The reason that we are all involved is to serve as a lighthouse project to Australia, to the world. It is a world scale engineering project.”
He goes on to say “10 gigawatts of solar, which should be the largest, if not at the time it is built, definitely the largest solar farm that exists today, connected to 22 gigawatt-hours of storage.”
As they say, “you can say that again Cecil”.
When talking about batteries he says: “It is 150 times bigger than the world’s biggest battery, the Tesla facility at Hornsdale…. I’ve got friends that know about storage,” he said. “You ring them and ask them for 100 megawatt-hours, it’s totally different. You ring them and ask for 22 gigawatt-hours. They’re like, ‘wait you mean 150 times bigger than South Australia?’ I’m like yeah”.
I’m like impressed yeah. He needs to get the calculator out; like it’s actually 220 times bigger like, (sorry, I’m just trying to get into the youth vibe).
I have looked at a few proposals for 100MWh batteries in SA and the going rate is around $100 million each, so one million per MWh or one billion per GWh. So the 22GWh battery is likely to cost $22 Billion alone. It will probably last 8 to 10 years before needing replacement.
The number of solar panels is equally impressive. The biggest I can find are rated at 500 watts so you need 2 per kilowatt, 2,000 per Megawatt and 2,000,000 per Gigawatt, giving the number of panels needed for 10GW as 20 million. These might last 15 years or perhaps a tad longer but their efficiency will degrade over time.
Apart from the vast area needed to house these and the infrastructure to support them there will also be the need for power inverters to convert from 12DC to AC so the voltage can be raised before converting again to HVDC for transmission. The terminal end of the cable also needs inverters and transformers to get the juice back to useable voltages AC.
I read somewhere that the “export” would be 3GW and I presume that the Singaporeans want it to be constant. With all solar installations the trick is to balance the load, generation and deficits over the day so there can be a constant output. This is usually where reality collides with dreams. I tried to pick a “typical day” and the chart below is for 21 December. It should be a good one because it is the summer solstice where there is a maximum sun angle. Unfortunately things like clouds get in the way and theory departs from practice.
For this day total generation is 34.3 GWh, total consumption is 72 GWh and the deficit is 37.7 GWh which is presumably made up by taking from the 22 GWh battery but there is not enough juice in the box. Also, once you take from the battery you have to re-charge it and the question is from where? Just by way of explanation for those who wonder, the GWh is taken directly from the Generation in GW multiplied by the time interval which equals one hour.
The only way to balance it is to reduce the load which means that the 3 GW will be reduced. Perhaps I am missing something or perhaps they are. I recognise that I am an old bloke and therefore suspect, but always willing to learn, yeah.
The cable might also be an issue. Currently the longest power cable is the NorNed that connects The Netherlands with Norway and it is 580 kms long. The connection to Singapore is around 3,800 kms. The deepest power cable is the SAPEI that connects Sardinia to mainland Italy and it gets to depths of 1,500 metres. The sea floor between Australia and Indonesia/Singapore extends over the junction of 3 tectonic plates and contains one area known as the Weber Deep that gets to 7.2 kms depth. Basslink cost around $900 million for a capacity of 500 MW and a length of 370 Kms. This project needs a capacity of 3,000 MW and a length of 3,800 kms – guessing $9 to $10 billion or more.
Perhaps they could name it the “Darryl Kerrigan Project”.