Digital grids: turning energy uncertainty into opportunity
Three trends rule the energy sector – decarbonisation, decentralisation, and digitisation.
To meet the UK’s environmental and sustainability goals, it has become imperative to decarbonise the grid, incorporating a large proportion of low carbon sources into the energy mix.
This is transforming our system of energy generation from a centralised system to a decentralised model, comprised of small pockets of generation from wind farms, solar panels and even electric vehicle batteries. To incorporate these changes, the grid is becoming more digitised - moving towards a two-way flow of energy where ‘prosumers’ play an active part in grid balancing and energy management.
To protect the digital assets of this new, omnidirectional grid, distributed services operators (DSOs) and distributed network operators (DNOs) must improve and modernise their protection relay solutions, whether it’s through installing new relays or retrofitting existing equipment with smart capabilities. This will save operators money by making maintenance easier, protecting staff from arc flashes and safeguarding the other equipment in their networks.
Out with the Old
Protection relays are digitally operated switches that trip a circuit breaker when a fault or issue has been detected, preventing further problems. It is critical in preventing abnormal activity or adverse conditions that risk damaging important and expensive equipment. Ultimately, protection relays are protection for power systems, there to ensure a continuity of service which protects your employees and the power security of end-users. So, why implement smart protection relays, and what are the drawbacks of legacy solutions.
Power security is critical for consumers relying on utilities for their energy supply. Faults and issues at substations can cause blackouts and major disruption. To make energy supply more resilient and reliable, problems need to be identified, located and resolved rapidly. Although so-called digital relays have been the industry norm for several years, they are often imprecise, not showing the location of the fault and making it more difficult to find and resolve.
Safety is an area that will be better developed with a smart solution. Detecting a problem early contributes to keeping your employees and equipment safe. The longer a fault or problem persists the worse it will get, increasing the chances of a dangerous arc fault or flash (dangerous explosions that result from circuit damage). A more efficient solution network will be able to detect faults before they become problematic.
Cybersecurity is a new consideration for energy operators. Equipment damage is no longer the only danger facing utilities. The energy network is now a target for a wide range of cybercriminals and state actors. Having digital relay solutions is no longer enough – they also need to be cybersecure.
With modern energy use, one weak link could have a calamitous effect - compromising stability, and the optimum delivery and storage of energy. Subsequently, we are at a stage where traditional relay solutions are no longer enough. Today a more connected offering is required if energy operators are to deliver on the next level of service expected by consumers, such as cheaper energy prices for variable-voltage overnight EV charging which allows operators to reduce grid load.
As energy the energy mix becomes more diverse, maintaining the integrity of these next-gen network grids will require efficient, advanced relays that work to minimise downtime by automating processes. Add to that, the rare but recognised risk of security means that utility companies must upgrade protection relays to enhance safety and minimise the loss of costly equipment.
One of the major benefits of a connected solution, is that it allows utilities to exploit a system of ‘predictive maintenance’. Most utilities follow a ‘preventative maintenance’ approach where equipment is checked by technicians/ engineers on a regular but strictly scheduled basis. The problem with this approach is that the likelihood of solving an issue, such as a minor fault or physical damage to the equipment, is left purely to chance.
You can’t respond to issues in real-time, you simply hope a technician finds the problem the next time they perform their checks. In the meantime, that minor fault could snowball into a business interrupting crisis. This could be anything from a power cut that leaves millions without power, to an arc flash which risks personnel safety and the integrity of equipment in a whole facility.
What’s worse is that after the crisis is over you need to then pay for repair costs. These are usually much more expensive than traditional maintenance due to the amount of work involved and potential need to replace a whole section of your facility’s energy grid.
With a connected solution – like a connected protection relay – utilities can monitor equipment condition in real-time. Any issues, software problems or faults will be flagged immediately and sensors within the cabinet can shut down operations within milliseconds. This allows operators to be proactive and schedule maintenance when equipment actually needs it, resulting in less frequent but more effective maintenance. Operators can react to problems in progress and, based on the data collected from equipment, even predict when the next round of maintenance is required. This approach avoids unnecessary and dangerous crises and creates cost efficiencies, both in terms of maintenance and repairs.
Reducing costs and boosting efficiency through hastening the fault detection and resolution processes, are critical to optimising energy networks by doing more with less. This is where smart protection relays play their part, enabling DSOs to deliver a more reliable supply to end-users. Those that are embracing this digitally enabled approach to provide an enhanced service to end-users, are well on the way to improving grid resilience and meet the future of a connected, carbon neutral grid.
This article was contributed by Alexandre Golisano, Strategy Director Power Systems UK & Ireland at Schneider Electric.