Thread by @flexibledragnet

@BieglerTom @factchekka @mcannonbrookes @simonahac Tom! I'm so glad you asked. To lay it out for you will be a bit of a thread, so please bear with me. Reference for numbers are Lazard 12.0 and the new study by ITP on dispatchable renewables by Keith Lovegrove available on the ARENA website. 1/n

@BieglerTom @factchekka @mcannonbrookes @simonahac Old power generation system was baseload, intermediates and peakers. Intermediates provided baseload backup when required & met increased demand. Peakers only came into play at times of extremely high demand. Peakers has low capital costs and high fuel costs. 2/n

@BieglerTom @factchekka @mcannonbrookes @simonahac New power generation system will be basecost renewables (when sun shining and wind blowing) with backup/intermediate demand met by flexible renewable dispatchable sources. Batteries, pumped hydro, solar thermal and demand management. Extreme demand - "all in" 3/n

@BieglerTom @factchekka @mcannonbrookes @simonahac If you would like a week's liquid fuel backup for when the wind doesn't shine and the sun doesn't blow - NH3. Made from renewable H2, 2.6 MWh/tonne. South Australia could be comfortably be backed up for a week with 100,000 tonnes and $2 billion in capital plant (2GW recips) 4/n

@BieglerTom @factchekka @mcannonbrookes @simonahac So now the thing to do is compare the cost of the two systems. For the sake of simplicity, I will ignore network costs (which is a worthwhile, but tangential discussion) and concentrate on the generation mix. And I'll also assume we are building from scratch. 5/n

@BieglerTom @factchekka @mcannonbrookes @simonahac Let's start with basecost renewables. Wind & solar are now the lowest cost of newbuild generation (Lazard 12.0). Unsubsidised solar US$ 36-46/MWh, wind US$ 29-56/MWh compared to coal US$ 60-143/MWh, CCG US$ 41-74/MWh and nuclear US$112 -189/MWh. Note: US gas price is 1/3 ours 6/n

@BieglerTom @factchekka @mcannonbrookes @simonahac Now let's move onto storage. Lovegrove looks at multiple time scales, 1, 6, 12 & 24 hours and finds different options at roughly twice the cost per MWh as renewable generation alone. Note that this includes the cost of the generation to charge the storage. 7/n

@BieglerTom @factchekka @mcannonbrookes @simonahac Results: 1 hr storage, wind/battery $102/MWh, solar PV/battery $124/MWh. 6 hours, wind/PHES (pumped hydro) $116/MWh, solar PV/PHES $126/MWh, CST (concentrated solar thermal) 4134/MWh. 8/n

@BieglerTom @factchekka @mcannonbrookes @simonahac 12 hours storage. Wind/PHES $115/MWh, solar PV/PHES $127/MWh, CST $122/MWh. 24 hour results similar prices for wind solar and CST.

So dispatchable renewables are less than new build baseload nuclear, in the centre of the baseload coal band and more expensive than US gas. 9/n

@BieglerTom @factchekka @mcannonbrookes @simonahac But of course US gas is cheap. Aus gas at (say) $8/GJ is a fuel cost of $56/MWh before capital and O&M costs. The trouble for expensive capital plant is that one needs to maximise capacity. But as W&S generate at a lower cost than new build conventional running at maximum CF 10/n

@BieglerTom @factchekka @mcannonbrookes @simonahac they will always be able to bid into the market lower and hence be taken. No priority dispatch, no subsidies, just pure economics.
So it is cheaper to build a renewable plus storage generation system than a conventional generation system. Challenges, yes, insurmountable, no 11/n

@BieglerTom @factchekka @mcannonbrookes @simonahac Finally, you mentioned pumped hydro and the public antipathy to new dams. I agree with you on run of river dams, but PHES is not run of river. It is isolated connected storages utilising a closed loop and not taking water from agriculture or environment. Minimal issues IMO. 12/12