THURSDAY, 4 JANUARY 2024Though electricity use accounts for 20% of current global energy consumption, it is an indispensable resource in our increasingly digital society. As the world transitions away from fossil fuels like coal and natural gas, renewable electricity – which can be generated from climate-friendly sources– will become a vital source of energy for both industry and domestic use. However, recent events like the Texas blackout of 2021 have demonstrated the vulnerability of the electricity grid in the face of hazards – an issue that will be aggravated as we approach net-zero and society becomes even more reliant on electrical power.
HOW IS ELECTRICITY GENERATED AND SUPPLIED?
Electricity is generated when mechanical energy is converted into electrical energy, via a turbine generator. The turbine can be powered by different energy sources: in 2021, 40% of the UK’s electricity was generated from natural gas, 40% from renewable sources, and the remainder from nuclear power and other fossil fuels. Electricity is then distributed to consumers through the national electricity grid. To keep the grid operating successfully, the supply and demand of electricity must be carefully balanced, and the electrical current kept at a stable frequency (around 50 Hz in the UK). Power blackouts can be caused by physical or digital failures within the electricity grid, or if the system operator deliberately disconnects the power if electricity supply is expected to be lower than demand.
Electricity grids are made up of a myriad of components and operating systems, all of which are susceptible to environmental and socio-economic hazards. Firstly, poor weather conditions can adversely affect the energy supply chain and transmission system: strong winds bring down power lines; heatwaves reduce the efficiency of electrical equipment; and flooding can damage equipment throughout the supply chain. In February 2021, Storm Uri overwhelmed the Texas power grid by plunging the state into freezing temperatures. Electricity generators of all types broke down because power plants were not equipped for the harsh winter conditions. Electricity demand from consumers far surpassed the available supply, forcing the regional electricity operator ERCOT to order an intentional blackout across much of the state. This decision inadvertently cut power to several natural gas producers, which exacerbated the problem as the producers couldn’t supply enough gas to the electricity plants. Ultimately, 5 million Texans lost power to their homes and businesses for several days, and nearly 250 deaths were attributed to the blackout.
As society becomes increasingly digitised and online, a report from the Energy Research Partnership has identified cyber warfare as a key threat to national power grids. The Ukrainian electricity grid was hit by a cyber attack in 2015, attributed to a Russian hacking group. The event left nearly 1.5 million people without electricity for several hours; power was quickly restored, but through physical interventions rather than the recovery of the weakened digital systems. Ukraine suffered several more attacks throughout 2016, and as the Russia-Ukraine conflict continues, the likelihood of further state-sponsored attacks only increases.
If terrestrial hazards weren’t enough, another serious consideration is the effect of “space weather”. The sun emits solar energy and plasma which interacts with the Earth’s atmosphere and magnetic field. On their own, space weather events can generate ‘excited’ currents within the electricity grid, damaging equipment and causing power fluctuations. If the grid is already near peak demand due to storms or heatwaves, a space weather event can push the grid beyond its capacity. This was the case for 6 million residents of Quebec in 1989, where the grid was hit by both a snowstorm and two solar plasma ejections within the space of a week, leading to a regional blackout lasting nearly half a day. Scientists are particularly concerned about the impacts of space weather as we approach a ‘solar maximum’ in 2025: a period of intense solar activity which occurs every 11 years.
When discussing potential hazards to the electricity grid, the elephant in the room is climate change, and unfortunately the issue here is two-fold. For nations to reach their net-zero emissions targets, fossil fuel usage must dramatically reduce over the next few decades. As electricity can be generated from renewable net-zero energy sources like wind and solar power, we will see increasing ‘electrification’ of industrial and domestic processes, displacing the need for fossil fuels. Transitioning to a net-zero society will create huge structural change within the energy industry, as power grids must both adapt to new energy sources and expand to service the increasing demand for electricity.
However, as we saw above, power grids are susceptible to adverse weather conditions, but climate change is making extreme weather events increasingly common. As detailed in BlueSci Issue 48, a warmer climate increases the likelihood of heatwaves, flash floods, hurricanes, and wildfires. Data from the US Department of Energy shows that power outages in the US linked to severe weather events have risen from around 50 per year in the early 2000s, to more than 100 per year on average over the last five years.
CREATING A MORE RESILIENT GRID
As society moves away from fossil fuels, the electricity grid must ensure uninterrupted availability of electrical power, withstanding and quickly recovering from any disturbances. Fortunately, there are many organisations and stakeholders working to improve the resilience of the electricity grid.
The Convergence Hub for the Exploration of Space Science (CHESS) is a US-based research project that aims to improve society’s resilience to space weather. As well as predicting hazardous space weather events, CHESS investigates the potential impacts of space weather on the electricity grid. In April 2022, CHESS ran a workshop for researchers, policymakers and grid operators, where they simulated a large solar plasma ejection. They determined how the event might affect the power grid in northeastern US and mapped out communication lines between different institutions. This community-wide exercise served not only to improve the future resilience of the grid, but also to expand interdisciplinary connections within the entire ‘sun-to-power-grid’ system. The workshop finally made several recommendations to policymakers, such as conducting further research into how the power grid relies on telecommunication systems (which themselves might be damaged during space weather events).
In the UK, the UKRI-funded ARIES project (Adaptation and Resilience in Energy Systems) will investigate how climate change may affect the UK’s energy systems. ARIES will model the impacts of changing weather conditions on current and emerging energy generation technologies, and how the energy grid might withstand these emerging hazards. ARIES will also investigate how climate change might affect the availability of weather-dependent energy sources like wind power.
ENERGY SECURITY FOR THE FUTURE
The UK National Grid has unveiled a new ‘Whole System’ approach to energy production, encouraging collaboration between industries to build a resilient, fair, and affordable energy system for all consumers. This was followed by the recent announcement of a ‘Future Systems Operator’, a new government body which will oversee the UK’s energy system. As the size and complexity of the energy grid increases, collaboration and interdisciplinary discussion is vital. But as helpful as these new strategies may be, policy-makers must put actions behind their words if we are to ensure energy security as we head towards net-zero. Society’s dependence on electricity is far greater than when the grid was first developed, and future hazards affecting the electricity grid could have a far more devastating impact on society than today. We must ensure that new infrastructure is built with the resilience to meet future energy needs.
Lizzie Knight is a 4th-year PhD student in Earth Sciences at Fitzwilliam College. She is interested in science policy, the energy transition, and 'net-zero' solutions. When not thinking about science, Lizzie can normally be found in a rowing boat. Illustration by Sumit Sen.