This month Storm Arwen ripped through parts of Scotland and the north of England, leaving destruction and devastation in its wake. Stories of farmers having to dig their sheep out of snow drifts, hundred-year-old trees being ripped from the ground, and a rare turtle from the Gulf of Mexico washing up on a Welsh beach, all showed the scope of this extreme weather event.
One of the effects of the storm has been the disruption to power supply, with residents in Northumberland, the Northern Peak District, Southern Lakes, Aberdeenshire, and Perth most affected. Initially millions were left without electricity; after five days the number was reduced to 30,000 residences, most of which are in remote locations. Although a week without power in the depths of December sounds rather unpleasant, there has been a heroic effort by engineers and power companies to get supplies back on for 97% of those affected.
The storm has been called the worst for 25 years; a once in a generation event. But business secretary Kwasi Kwarteng has warned the public that extreme weather will become commonplace as climate change continues. Storm Arwen is also unusual as, historically, storms are more likely to cause landfall on the UK’s west coast. But the easterly winds are thought to be the source of the damage. Elderly trees and loose branches are not usually blown so strongly from that direction, and are more likely to come loose and damage power lines.
These events raise questions about the resilience of the UK’s power grid, especially when our transition to a green economy will mean more electricity use.
The State of Electricity Use in the UK
In 2020 it was found that the UK’s electricity use was at its lowest since 1983. This was largely to lockdown measures imposed during the pandemic. However, electricity use had already been reducing year-on-year in the run up to this. The trend was due to introduction of energy efficient appliances and off-shoring of heavy industry. But this downward trend is not fated to continue. As fossil fuels are phased out, renewable energy powered electricity is set to replace many of our everyday energy uses.
If every car and taxi (excluding other transport like road haulage and buses) were to be electrified tomorrow, enough electricity to power the 280 billion miles a year they travel would need to be found. This equates roughly to 70+ terawatt hours per year; coincidentally the same amount of wind energy produced in the UK in 2020.
Currently 80% of home heating uses gas. All of this will need to be replaced by low-carbon heating systems, most commonly heat pumps. The exact amount of energy required to power electric heating systems is difficult to calculate. Variables including what kind of pumps are installed, as well as other retrofitting measures, need to be taken into account.
However, just as with electric vehicles (the sales of which tripled in 2020) electric heating systems are only going to increase in popularity. The UK government is seeking to have 600,000 heat pumps installed per year by 2028.
How do we Add Resilience to the National Grid?
There are two main reasons for power outages; disruption to infrastructure and lack of fuel.
In the 1970s, power cuts in the UK were caused by industrial action, and they were avoided in 1980 due to stockpiling of coal. However, it remains extremely tricky to stockpile renewable energy in this way due to difficulties with storage. Solutions are being explored, including batteries, storing leftover energy in hydro dams, and most promisingly thermal electricity storage.
But weather proofing the grid is a different issue. To avoid blackouts of the future halting transport and switching off heating and lights, some changes are recommended. Steps such as undergrounding wires so they are not affected by high winds, strengthening towers and replacing wooden poles with more solid concrete ones, could all help to ensure our infrastructure is weather-proof.
To an extent this is already happening. According to Ross Easton, director of external affairs at the energy networks association, providers have put 700 million into resilience in the last five years, 150 million of which was invested last year.
Doing this on the scale required won’t be easy, and the government will be ordering a review into resilience measures put in place by electricity companies in the wake of Storm Arwen.
We can only hope that those still without electricity as I write this prove a lesson in resilience for the companies that run our power grids.