The UK National Power Grid is the high-voltage electricity transmission network which distributes power from its power stations and sub-stations to all parts of the network. Energy from all sources (traditional and renewable) is integrated onto the network to satisfy demand, as required. Click here and here to see real time supply and demand for the UK grid.
Black-outs, what Black-outs?
So, how close did we come to the total collapse of our national electricity network this year? Was it all just fear-mongering & nutty conspiracy theorists OR is it a crisis just waiting to hit us sooner, rather than later?
It’s no secret that the UK’s National Grid was expecting to experience severe pressure this winter, with some experts even saying it could approach breaking point this year, resulting in potential black-outs. In response to this, in October 2022, the Government laid out its emergency strategy for possible electricity rationing during the winter months, if necessary.
Thankfully though, this winter has been very mild so far, which has meant less strain on the network than might otherwise have been the case.
In truth, there was no real imminent danger of experiencing widespread, wholesale or long term power grid failures this year and likely not next year either, but have no doubt, if we sit on our hands and do nothing……it will come, and it will hurt! Until now, the UK power grid has been relatively stable, reliable and capable of meeting the country's electricity needs and more. However, as demand increases going forward, the ageing power grid infrastructure poses some challenges that the National Grid and others must work to address.
So……we managed to dodge a bullet this year……but what about the next few years?
As the government is committed to net-zero carbon emissions by 2050, we need to do two things urgently to ensure the worst case scenario never becomes a reality;
1. Significantly increase the amount of renewable energy we generate to lower our carbon emissions and;
2. Make significant investments in both our national infrastructure and our distributed networks to include more battery (and other) storage to offset any intermittency issues created from the increased renewables as reported in our <previous articles>.
For now though, until these new technologies are deployed in volume, which can be a lengthy process, we must focus on stopping the lights from going out, on several fronts! Most of the UKs energy is currently generated by burning our own gas or from gas imported from local neighbours, and this is likely to continue to be the case for some time to come.
Even though the UK has never been directly reliant on Russian gas for our power generation, as expected, the war in Ukraine has caused knock-on constraints from other affected countries, which we do import from. Although it was seen as only a remote possibility of experiencing black-outs this year, it was still deemed necessary by the Government to have a “just in case plan”. These emergency plans resulted in the roll-out of the Demand Flexibility Service whereby some UK consumers and businesses can be incentivised to restrict their usage and demand to outside of peak times to help smooth the demand with respect to supply.
Topology of the UK’s National Grid network
The topology of the UK's national grid system is a transmission and distribution network that is divided into two main parts, both of which need to upgraded going forward;
This is the high-voltage network that connects power stations to substations across the country. It operates at voltages of 132-400 kV and is responsible for transmitting electricity over long distances. The transmission system is operated by the National Grid, which is responsible for ensuring that electricity is available to meet demand, and for maintaining the security and stability of the grid.
This is the low-voltage network that connects substations to homes and businesses. It operates at voltages of 11-33 kV and is responsible for distributing electricity to the final consumers. The distribution system is operated by a number of different companies, known as distribution network operators (DNOs), who are responsible for maintaining the distribution network and connecting new customers to the grid.
The UK's national grid system is also connected to other European countries via interconnectors, which allows for the exchange of electricity between different countries and helps to balance supply and demand.
The grid is a complex system, with multiple generators, transmission lines, substations, transformers and control centres that work together to ensure that electricity is delivered to consumers in a safe, reliable, and efficient manner when it is required.
What are the critical challenges?
The UK's national grid has an ageing infrastructure that is in desperate need of upgrades and constant maintenance. This infrastructure includes power plants, substations as well as transmission and distribution lines which have been in operation for decades. These older components are more prone to failure and are less efficient than newer technologies and also require significant, time-consuming maintenance to ensure they are robust enough and kept up to a reliable standard.
One of the main challenges with the UK's ageing infrastructure is that it was never originally designed to handle energy inputs from multiple sources, most notably renewables. Most of the technologies causing the design issues today simply did not exist in any meaningful way when the grid was designed. The grid was primarily designed to be fed from baseload generators such as coal-fired power stations. Now with the closure of many of these coal power stations, the drop in the constant baseload and the rise of renewable energy sources has introduced a mix of energy sources which the grid was never designed to cope with. This has made it more difficult to balance supply and demand and has increased the risk of blackouts. Frankly it is testament to the ingenuity and hard work of National Grid and the other operators that the network has coped so well.
Integrating new technologies
Another challenge with the UK's ageing infrastructure is that it is not well-suited for integrating new technologies, such as electric vehicles and energy storage systems. This can make it difficult for the National Grid to manage the integration of these new technologies, which is essential for achieving the government's goal of net-zero emissions by 2050.
To address these challenges, the UK government has announced plans to invest in upgrading and modernising the national grid's infrastructure. This includes upgrading existing power plants and transmission lines, building new substations, and investing in new technologies such as energy storage systems and interconnectors.
The National Grid is also working on the ‘Future Energy Scenario’ which aims to provide a flexible and responsive grid system that can efficiently integrate new forms of generation and consumption, such as the electric vehicles and distributed energy resources mentioned above.
Balancing power loads
It is difficult for the UK National Grid to balance the inputs from renewable sources and fossil fuels because renewable sources are inherently intermittent, meaning that their generation can fluctuate depending on weather conditions. As we reported in a <previous article> , this can make it difficult to predict how much electricity will be available at any given time, which makes it challenging to balance supply and demand unless energy storage is introduced.
Fossil fuels, on the other hand, are considered as base-load power sources, meaning that they can generate power consistently and can be dispatched at any time to meet the demand. However, the UK has committed to phasing out the use of fossil fuels as part of its goal to achieve net-zero emissions by 2050, which means that the National Grid needs to find ways to balance the load with these inherently intermittent and variable power sources.
This is certainly not a new dilemma for our National Grid. We have known about the challenges and are using a variety of methods to balance supply and demand already. These include adjusting the output of power stations, importing electricity from other countries via interconnectors, and using demand-side response programs to incentivise businesses and individuals to reduce their energy usage during periods of high demand, which the government re-spun this winter when they needed to issue an Emergency Plan to safeguard the grid from over-demand scenarios.
However, managing a power grid with a large share of renewable energy requires a more advanced and sophisticated balancing mechanism to ensure that supply and demand are always in balance.
As we reported previously, this is made possible by deploying Battery systems into the mix to store the excess electricity generated during peak production and storing it for release later to balance the demand. e.g. when solar and wind are not generating.
Long seen as the missing link between intermittent renewable energy and constant reliability, energy storage is now playing a wider role in the energy transition than ever before, with the potential to enable the eventual decarbonization of our energy systems.
Trina Storage is at the forefront of Battery technology and continues to implement large utility-scale battery solutions, in order to overcome the challenges presented by the renewable energy transition and help National Grid keep all our lights on.
Why not give us a call to find out more?