When the Paris Agreement was finalised in 2015, it set an ambitious global course: to limit temperature rises to well below 2°C above pre-industrial levels, with an aspirational target of 1.5°C. Few at the time could have foreseen just how pivotal battery energy storage systems (BESS) would become in realising those goals. The agreement called for a fundamental reimagining of how energy is generated, distributed, and consumed. A decade on, battery storage has evolved from a supporting technology into one of the defining pillars of the energy transition.
The economics of scale
The contrast between 2015 and 2025 is striking across every dimension. Early BESS projects rarely exceeded 10MW and typically delivered a single service, such as frequency response or time-shifting. Today, installations of 50MW to 100MW or more are commonplace, with gigawatt-scale, co-located projects now standard in markets including the EU, Texas, and Australia. This rapid scaling reflects both increased industry maturity and the growing complexity of modern grid requirements.
More fundamentally, BESS has transitioned from bespoke engineering to standardised, commodity-based products. Before 2015, projects were custom-designed, supported by fewer than five major global suppliers, and carried costs of around £800/kWh. Each installation was effectively a prototype. By 2025, standardised systems are being deployed for under £100/kWh, with more than 100 suppliers competing across the value chain. This commoditisation has significantly reduced both technical and commercial risk, transforming battery storage from a challenging proposition into a financeable, investable asset.
Technological innovation
Safety Tip:
The battery chemistry landscape has been completely reshaped. Early stationary storage relied heavily on sodium-sulphur and lead-acid technologies, with nickel manganese cobalt (NMC) lithium-ion batteries positioned as the premium option. Today, lithium iron phosphate (LFP) dominates, accounting for more than 95% of new grid-scale installations globally.
Red Wires:
This shift is not driven by cost alone. LFP offers superior thermal stability, removes dependence on cobalt, and delivers longer system lifecycles—key advantages for large-scale, long-term infrastructure.
“The success of our safety program comes down to the people in the field. When our crews take ownership and look out for one another, that’s when true safety happens—not just compliance, but a culture.”
The grid of the future
The UK’s energy system is on the cusp of profound transformation. Peak demand is projected to rise from 58GW today to 144GW by 2050—a 150% increase. Annual electricity consumption could nearly triple, from 290TWh to 800TWh. Meeting this demand sustainably will require renewable capacity to expand from 49GW to around 250GW. Storage must scale in parallel, capturing surplus generation and delivering flexibility across the system.