151–160 of 175 posts
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Its shockly poor procurement - those new trains are not fit for purpose.
Do you mean that they don't meet the requirements of the tender spec ("not fit for purpose") or that the spec in the tender process was deficient ("shockingly poor procurement")?
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Batteries are great for this kind of stability support. I actually work for an Australian company that aggregates residential batteries together into MW-scale units and provides coordinated responses from 1,000 of kW-scale batteries that just as capable as a MW-scale plant (at a much lower cost of capital). Here's one of our plants in Canberra which is past 3MW now, and is the first of its kind to be approved to bid…
Interesting! I've been following this through cleantechnica, electrek & other sites. It's transforming a complex heat/fluid/mechanical system issue into a computer network and security issue. Usually the home network internet access market is very concentrated so a failure there could make the VPP unavailable. Solvable by putting control servers in various places and having each box connecting to multiple redundant c…
One nice thing though is many of the stability services (such as balancing frequency) can be detected locally and therefore centralised dispatch and comms aren't necessary. All of our household systems have high speed metering attached (sampling at 20hZ) and when they make a frequency measurement outside the normal operating range (48.8Hz - 50.2Hz) they discharge/charge respectively. This means that when there's an event we have all the systems reacting in a way that looks coordinated, but is actually just syncronised (as they all essentially have the same input -- grid frequency), so services like this are extremely resilient.
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Its shockly poor procurement - those new trains are not fit for purpose.
Do you mean that they don't meet the requirements of the tender spec ("not fit for purpose") or that the spec in the tender process was deficient ("shockingly poor procurement")?
It actually sounds like this was really useful though, as a lot of the systems involved will be improved in the future. I'm not sure if the grid is already doing this, but they should trigger failures randomly, including Low Frequency Demand Disconnection schemes from time to time to ensure that all downstream systems are also ready (like the hospital someone mentioned that had an issue with the backup generator, or…
Triggering demand disconnection randomly is saying "we should provide consumers a service including deliberate random blackouts". That's OK in contexts like Netflix where the downstream systems are supposed to be able to be resilient to faults and failures are comparatively low-stakes anyway. But almost all grid consumers aren't resilient to power loss (would your house continue to be fully functional without noticea…
The question is: Should we cat power to 5% of the customers now, or let the whole electrical grid stall, resulting in zero power for anyone.
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I read your list and see a bunch of 'technical debt.' Trains put into operation without the ability to survive a power transient without intervention. Life critical backup power system failures. The set of critical sites is not being maintained properly. In my mind these failures are are not entirely unrelated; reliable power is taken for granted and the testing and maintenance necessary to cope with power outages is…
> Trains put into operation without the ability to survive a power transient without intervention. The trains were built to a environmental tolerance spec, and shutting down when that spec is exceeded seems like a reasonable thing to do. Having an expert test that all the safety systems are still working properly after they've been exposed to conditions they weren't designed for also seems prudent. Do you think peopl…
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Well, that and decentralizing your power infrastructure.
Decentralized grid will have less ability to deal with spikes in load, and be more unstable as a result. Question in cases like this is often - do you want to have a lot of smaller outages all the time or bigger, but less common outages.
... until the big disaster actually happens at which time at which point it's simply criminal that such things were allowed to happen.
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That makes me wonder, if you were standing next to these turbines would you be able to here them slow down?
Probably, although you are more likely to hear the 3000Hz to 2880Hz change in the generator RPM than the 50 to 48.8 change in the output.
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Interesting! I've been following this through cleantechnica, electrek & other sites. It's transforming a complex heat/fluid/mechanical system issue into a computer network and security issue. Usually the home network internet access market is very concentrated so a failure there could make the VPP unavailable. Solvable by putting control servers in various places and having each box connecting to multiple redundant c…
Skinny, cheap comms such as LoRa would be perfect for redundancy. If you can at least get a simple message to the batteries (charge/discharge at xkW) you still have most of your effectiveness of the system. One nice thing though is many of the stability services (such as balancing frequency) can be detected locally and therefore centralised dispatch and comms aren't necessary. All of our household systems have high s…
Presumably you need comms later to add up how much frequency support you ended up providing, for market settlement?
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Yes, batteries are very fast acting, but that battery in South Australia is only 100MW and the grid lost over 1400 MW. https://www.news.com.au/technology/innovation/inventions/eve... Batteries have a lot of potential, but they are currently small in capacity.
> but that battery in South Australia is only 100MW and the grid lost over 1400 MW I hear this kind of misconception fairly often and so it is worth noting that you don't need 1400 MW of battery to protect from this event. The initial 735 MW drop happened, as I read TFA, when a major generating source took itself offline as a result of the frequency disturbance . The later generator drops are cascades of the frequenc…
So far the largest battery is 40 MW? So not really going to help more than 40 MW can, even if it comes online instantly, when 200 MW trips off.