SOUTH AUSTRALIAN SUPER-BATTERY, or why I disagree with Elon Musk on batteries for renewables. (I disagree with great sadness, as you might have noted I love everything else Elon does. 😉 )
I don’t get it. Say we take Elon Musk’s price of $250 / kilowatt-hour for the capital cost of his battery system. (There’s good reason to think it might be $500 to $600 per Kwh!)
Let’s compare it to a 1 gigawatt nuclear power plant. $250 / kilowatt hour storage is one millionth of the output of a GIGAwatt power plant. So to scale up to one gigawatt, multiply the cost by a million which is $250 MILLION! But we can’t stop there, the figure is $250 million for just 1 hour of output at 1 Gigawatt.
A battery that can store about 16 hours (as solar PV only works about a third of a day) would be 16 * $250M = $4 BILLION dollars to store just 16 hours power of a 1 Gigawatt power plant.
That’s not all. You haven’t built the power source yet, this is just the battery! You’ve still got to build all the wind and solar you need to charge this beast. Remember the rough rule of 3. You’ve got to build at least 3 times the power you need (in this case 3 GIGS of wind and solar) so that 1 lot can run your town during the day, and the other 2/3rd’s can charge the batteries for night time. Add in some cloudy weather forecasting and you might actually have to overbuild your wind and solar by 4 or even 5 times to be sure!
Then there’s another problem. These batteries might only last 12 years, but nuclear power plants can last 60 years. So you’ve got to multiply that $4 billion by 5, bringing it up to $20 billion, just for batteries. (You still haven’t built the solar and wind farms yet!)
And this is based on Elon’s battery only price of $250 / kwh, not the full $500 to $600 per kwh that Forbes thinks is more likely given cooling and other infrastructure costs.
But despite American nuclear being legislated into oblivion, there are good examples around the world that show nuclear power could be built for $3 billion, maybe even $2 billion per GW.
A nuke will run all day and all night, no matter the time of year. We are still so, so far from anything being a ‘saviour’ for unreliable wind and solar energy. In contrast, there are future projections for various modular breeder reactors that eat nuclear waste to come off the line at about $1 billion / GW.