LV networks – ready for anything?

The UK’s first Christmas in lockdown should reassure DNOs that their networks are in shape to cope with rising EV ownership.

By Jim McRae, Kelvatek

Rising EV ownership has triggered concerns that extra load from all those plug-in vehicles will stress the network taking customers off supply and triggering costly penalties for operators. But based on what we have seen in December, it appears that much of the UK’s distribution network is better equipped than some may have credited.

The nation’s first Christmas in lockdown posed a novel challenge for DNOs. Restrictions on household mixing meant large family gatherings were a no-go. Instead of travelling, people stayed in their own homes to watch TV, stay warm and cook dinner for themselves. With more ovens and electric heaters fired up, it’s no surprise that household power consumption increased sharply compared with the previous year. Data captured by one of Kelvatek’s load monitoring systems shows, the Christmas Day load on a representative substation peaked at almost 100kW higher than the same figure in 2019. Measured in car terms that’s equivalent to adding a dozen charging EVs to each circuit.

Above: Load Patterns from a typical LV substation – Christmas day 2020 vs 2019

Despite the unprecedented strain the LV infrastructure coped well, ensuring families across the UK were able to enjoy that all important Christmas dinner.

During December we issued over 700 reclose notifications to our DNO customers across the UK. These alerts advised customers where our smart devices had detected signals indicating the presence of a developing fault on a cable, with a calculation of the likely distance to that fault. Armed with this information, DNOs were able to send out engineers to sniff for fault gases. This allowed them to pinpoint fault locations, effect repairs and greatly reduce the risk of a fuse rupturing on Christmas Day.

On Christmas Eve and Christmas Day Kelvatek saw more than fifty successful reclosures of our smart devices, keeping customers on supply and avoiding costly penalties in customer interruptions and customer minutes lost.  Assuming roughly thirty households on each of those cable networks, that’s Christmas dinner saved in 1,500 homes. And what about those homes – fortunately not many – where faults did go permanent on Dec 24th and 25th? Armed with accurate fault location information, DNO staff were able to attend site, isolate or repair faults quickly and ensure households had power.

It is reassuring to know that our distribution networks are able to cope with the challenges of today and the expectant challenges of the near future, however this highlights just how vital network monitoring is going forward. What once would have been seen as a costly ‘nice to have’, network monitoring is now an essential element of network operations.

The latest example of Kelvatek’s commitment to helping DNOs understand and manage their assets more effectively and cost-efficiently is PRESense — our new, AI-enabled LV network monitoring solution. Powerful machine learning algorithms allow PRESense to identify subtle patterns and trends in network behaviour and power flows, helping build a detailed picture of likely fault activity, asset and network health.

Deployment of a powerful monitoring system, like PRESense will enable DNOs to identify, locate and repair faults much earlier in their development – in many cases well before a connected customer even realises that there is a problem. Similarly, monitoring the load from substations, such as that above, will allow early identification of any trends which will affect the networks capability to supply and take appropriate action to prevent the network becoming overloaded.