Energy security: how battery storage helps keep the lights on

Energy security shot up the political agenda following the Russian invasion of Ukraine in February 2022, resulting in a significant rise in energy prices.

Across Europe, countries grappled with their reliance on fossil fuels to heat homes and power businesses. Governments opted for expensive LNG imports, revived old gas storage sites and refired coal plants to manage demand over winter.

Substantially raising the cost of living or running a business, the link between global prices and energy bills in the UK raised the question of how energy should be priced, as well as generated, in a net zero system.

Although prices have come down in recent months, the issue hasn’t gone away - far from it.

This raises the question of how we avoid another winter of uncertainty, as further international conflict means how we source and price our energy remain critical for policymakers.

That context is key to the debate around the cost of transitioning to net zero and whether the UK should continue to exploit its oil and gas reserves. However, in the name of energy security, ministers announced legislation in November to mandate annual North Sea licensing rounds.

With steps like these, there’s a risk we lose sight of the opportunity that achieving net zero gives us:

1. investing in homegrown renewable power which brings down our bills in the long term
2. unlocking the potential of batteries in creating a more reliable, flexible and affordable system - all while meeting our climate targets
   

But net zero doesn't need to come at the cost of energy security. By prioritising the transition to clean energy, we can achieve climate targets and strengthen our energy security at the same time.

If done by growing renewable and storage capacity, achieving energy security could solve multiple issues.

Making cheap, green and reliable energy accessible to consumers across the UK relies on a number of factors. Breaking the link between global gas prices and consumer bills is one of them, something the Government consulted on as part of its review of electricity market arrangements.

Another is the need to throw our full weight behind building and connecting domestic renewable energy infrastructure. This includes wind, solar and, crucially, battery storage - or we won’t be able to store the power generated by intermittent energy sources.

Making the growth of renewable infrastructure a priority is essential. It means we can bring down energy bills in the long term and also help the UK achieve its net zero targets. It also means we reap the rewards of investing in the industry’s growth, creating new jobs or sources of economic revenue.

Homegrown clean energy – as opposed to importing supplies via tankers or trading expensive fossil fuels on global wholesale markets – and securing affordable power supplies for the future are two sides of the same coin.

Fortunately, we have the proven technology to help deliver both.

Battery storage plays a vital role in powering the UK’s electricity system, despite occupying a smaller share of the conversation around energy security.

For example, arbitrage - charging a battery when output is high (and cheap) to then discharge supplies when renewable output is low (and typically more expensive) - can keep prices down for end consumers.

Batteries provide a number of other solutions, including helping the electricity system operator:

1. ensure the grid’s frequency remains stable
2. manage constraints when power supplies outstrip customer demand.

Another service batteries can provide is called ‘black start’, usually tendered to storage site operators by an electricity system operator. If a system operator manages a full or partial blackout, batteries are able to respond quickly, or bolster plants which have already been brought back online, by discharging power when and where it’s most needed.

A rapid response like this can help boost supplies over winter - much more cheaply and quickly than the UK’s existing use of gas plants can.

Bringing more batteries onto the electricity system allows the UK to secure its energy independence.

This makes us less vulnerable to volatile international markets, easily stoked by geopolitical conflicts or turmoil in industry overseas.

It also helps lower energy bills in the long run. With more batteries at the system operator’s disposal, the more clean electricity we can store for use over peaks in demand - particularly during the winter when buying power at spot prices can be more expensive.

This winter will see us continue to fall back on fossil fuels when heating our homes or plugging any grid capacity crunches. As the UK increasingly deploys renewable energy infrastructure, batteries will be our real ally for securing energy independence - enabling us to rely on an electricity system powered by renewables.