Back in 2019, we finished an UG project creating a timeline of #HVDC projects πππ and also added the what was then the newly proposed π¦πΊπΈπ¬ #suncable project.
This just looked at one aspect (the most technically challenging of all βοΈ) the undersea cable.
There have been quite a few #BESS projects developed since then but all within the bottom left box where all π’are.
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In fact, we had to redraw the #BESS part of the project on an log scale in the x-axis to make a bit more sense of it!
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Back on the cable and based on 2021 costs and publicly available information, this provides a rough cost estimate (or at least an indication) for MW-km costs.
*Many of these cables do not go as deep as #suncable and Murraylink is underground, not undersea!
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A lot of commentary focuses on the losses across the cable, which, yes are going to be high in % due to the length, but as such a system would operate continuously and not intermittently, only affect the unit economics of $/MWh delivered in Singapore.
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Instead, here are some other technical challenges that need to be worked out
1. How to operate the #Solar & #BESS at that scale as an island? 2. The #Darwin connection? Does it taper as a multiterminal? Does it convert back to AC and then back to DC?
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3. How do you operate whatever you choose as the option from 2? 4. πΈπ¬ contingency operation? How do you plan for N-1 when one link is 15% of your infeed? 5. #BESS in πΈπ¬? 6. Maintenance and Faults? 6. How do the economics of all of the above stack up? 7. Competing supply?
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Really interesting to see how any and all of the above play out in the next few days / months / years.
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OK, most of the following is textbook stuff on #HVDC but just a quick reference for what a "low-voltage metallic return" - the faulty part of #Basslink - is used.
Basslink is a monopolar HVDC system and the original design was based on an earth return. This is quite typical of monopolar #HVDC systems as it reduces cost (requires only one cable) and losses (again because of one cable)
Reading through @OtherProfGreen summary of the 9th August #UK event, the similarities to the 25th August 2018 #Australian separation event across the #NEM are very interesting to observe.
Firstly, they are all attributed to lightning strikes.
And although the #UK one was easy to identify, the #QLD one took a bit of forensic investigation as it happened at a time that no weather warnings were out for the area.