00:05 – The hidden risk
So, the second theme we’re going to look at is looking at non-firm connections solutions. So, a firm connection for a data center would typically be two circuits or more to the site, such that if, if one circuit is switched out, they can stay on supply because the security of the supply for data center is really important. The same is true for the sort of upstream network capacity as well. So, as well as the two, three or more circuits that are connecting into your site; the upstream network has a limited capacity as well, and it might be the case that for outages of certain circuits or certain bits of the network, upstream of your connection, you might get your capacity reduced or you might get tripped off, and that would also be classed as being non-firm.
So, data centres will want to avoid non-firm connections as generally, as the long-term connection solution, but I think it’s important to set the scene that data centre connections are really big, some of them enormous. So a 500-megawatt data centre connection, is quite common at the moment, there’s lots of data centres of that size or bigger, looking to connect. But to get it into perspective, a 500 megawatt load is the size of a very large town or a small city. So, we’re talking about large point loads connecting all over the network; so, they’re going to have a really big impact on the network and the scale of these connections can trigger, works on the transmission system, and works on the transmission system can take quite a long time to do so if you need to replace the conductors, the wires on an overhead line that could take 3, 4, 5 years to do. If you need to build a new transmission circuit, you’re looking at 10 years to actually build a new overhead line circuit. So, timescales for reinforcement works are really quite significant.
01:56 – The dilemma
There’s then a dilemma potentially here for some data centers is to go, well, I want a firm connection, but I want to be connected quickly, because being connected quickly means you can potentially get access to more end customers, and get into the sort of AI usage and so on. So, this is where non-firm connections can really come into their own to go potentially as a stop gap solution between being energized and having a firm connection once some reinforcement work have been done on the network.
Maybe I’m going to be happy with a non-firm solution, so that’s being explored by quite a lot of data centres at the moment, and it’s something that we’ve helped data centres explore and some of the key challenges that we’ve helped developers look at are in the weeds of these non-firm connections because every non-firm connection’s a little bit different from the other.
02:56 – Early power options
So, one of the typical solutions is an inter-trip solution, whereby if something happens on the network, that could be an outage of a transformer or a circuit that an inter-trip is sent to the data centre to trip off either part of its load or all of its load. So, the impact on the data centre is going to depend on the nature of the inter-trip. So, if the inter-trip is based on a single outage happening on the network, that could happen at anytime 24/7, 365; and so, that’s quite high risk potentially for a data centre developer, they might have to keep their backup generators on site ticking over in the background all the time in order to, you know, come on at a moment’s notice if there was an outage to happen elsewhere on the network. If there is an inter-trip where it’s as a result of a second circuit outage, so not just one circuit or transformer being switched out, but one being switched out and then another one being switched out, and typically that would be a maintenance outage on one bit of kit, followed by a fault on another bit of kit, and in those circumstances it’s much easier to manage because during the maintenance outage, that’s when you start running your generators up in the background and keeping them warm, but that only might be for a week, two weeks, a month, or something like that, rather than all the time. So, digging into the nature of the non-firm arrangements is really important to try and understand what that looks like and the impact on the customers.
Another non-firm arrangement that might be available is a single circuit connection, which is going to be followed up with a second or third circuit at some point in the future. So it might be that there’s only one circuit breaker bay available at a substation now, and a data centre could connect into that circuit now, but then the second or third circuit break bay is not going to be available for 3, 4, 5 years or something, until some works are done at the substation. So the data centre developer then has to make that assessment, do I take the single circuit now and be at risk of an outage, a single circuit outage for a few years? Or do I have to wait until the second and third, whatever bay is available?
05:10 – Navigating the process
So, we will help developers think through that, think through the impacts, you know, how often might they go off as a result. So, where’s that single circuit connected into, is it just connected into a busbar? Is it connected off an overhead line? You know, what’s the risk of them going off supply? And the other thing that we do quite a lot of is actually working with the transmission companies to go, actually you haven’t provided a non-firm solution here and you know the connection date is a long way away, but actually is there a non-firm solution that, you can provide? You know, here’s some ideas about, what you could do, and just trying to engage with the transmission companies so that the developer gets the project and the solution that they want and that they need in order to get to that early power.
So all this is about early power, and that’s what the data centre developers want, and that’s what we try and help them get.
