Business energy bills in the UK are coming under fresh pressure as two major cost-drivers are escalating: TNUoS charges and the RAB Levy. The TNUoS fee recovers the cost of maintaining and reinforcing the high-voltage transmission network, essentially the “backbone” of power delivery.
According to the National Energy System Operator (NESO), TNUoS demand-residual revenue is projected to leap from about £3.84 billion in 2025/26 to £7.52 billion in 2026/27 — nearly doubling. For businesses this means much higher daily standing charges tied to their connection band and location, rather than just consumption.
Meanwhile the RAB Levy has been introduced to fund new nuclear power projects via the regulated-asset-base model. The cost is levied per kWh and will appear as an additional non-commodity line on bills, with initial rates set around 0.4 p/kWh (later rising) for supplier obligations.
Together these charges squeeze margins: TNUoS raises fixed infrastructure costs, RAB adds a new pass-through cost of low-carbon investment — both outside the typical commodity rate negotiations. Businesses need to revisit forecasts, scrutinise their tariff bands and negotiate contracts that account for elevated non-commodity charges. Ignoring them risks surprise jumps in standing charges and overall energy spend.
As the UK accelerates grid upgrades and low-carbon power capacity, these network and infrastructure cost-recovery mechanisms will become a permanent feature of business energy bills.
Contact Richard at Utility helpline for more information or help with business energy bills