Ofcom has set out a nuanced assessment of the range of possible objectives for mobile network resilience in the UK in comparison to some international peers
An update on its ongoing consideration of mobile power resilience and battery back-up
On 10 February 2024, Ofcom published a technical report and update on its call for input on power resilience in the mobile radio access network (RAN). The report further develops the analysis the regulator first published in December 2023 on the current state of power back-up at mobile sites alongside an estimate on the cost for extending that back-up across the UK. Since that consultation, Ofcom stated in its September 2024 statement on resilience in the sector that it was continuing to engage with operators and the Government on the issue of power resilience in mobile networks. In the meantime, the regulator has also updated its guidance for battery back-up in fixed networks, recommending four hours at the cabinet-level. Sir Chris Bryant MP (Minister of State for Data Protection and Telecoms, DSIT) has weighed in on fixed network resilience, coordinating with industry on commitments to provide more advanced battery back-up or other resilience solutions to vulnerable consumers through the PSTN switch-off process. While Ofcom’s latest report is limited to the mobile network, the regulator has nonetheless consistently justified its concerns with continuous power in the RAN in part through the resilience challenges posed by the PSTN switch-off and the loss of fixed-line services during residential power outages.
The regulator estimates that four hours of continuous access to emergency services would cost around £1bn for one operator to reach all masts in the UK
In its previous call for input, Ofcom estimated that the cost of providing one hour of battery back-up across the mobile RAN that is capable of supporting uninterrupted communications services is between £0.9-£1.8bn. To further develop its analysis, the regulator considers a range of objectives for power resilience, noting the possibility for a range of levels of service available during an outage and numbers of operators providing that service. The objectives are informed by the various negative impacts of power-related communications outages, from being unable to access emergency services to the interruption of productivity and broader economic harm. To provide “almost everyone” in the UK with four hours of continuous access to emergency services (but no other communications services), Ofcom estimates it would cost approximately £1bn for one operator to reach all of the masts in the UK. To provide uninterrupted communications services, it estimates that costs could range from £250m (minimum estimate for 15 minutes) to £4.4bn (maximum estimate for four hours).
Ofcom is clear in caveating its study as containing no cost-benefit analysis for battery back-up investment and notes that consideration of a number of factors not discussed in the report would be necessary to do so, including:
The appropriate balance of expectations between power supply reliability and telecoms-provided back-up;
The ongoing costs of back-up at mobile sites, including in relation to fuelling and theft or damage;
The need to target back-up at geographic regions more likely to experience longer outages; and
The continued development of satellite connectivity capacity and its contributions to network-wide resilience.
Though it refers extensively to international examples, Ofcom’s approach of considering scaled objectives for resilience offers greater nuance
As part of its research, Ofcom also provides an overview of mobile network power back-up requirements in a range of countries around the world. Of the 19 countries it includes, Ofcom found that six have a specific obligation for operators to provide universal back-up at mobile sites, with the longest regulated duration being six hours for rural or particularly important sites in Estonia, Finland and Romania. A further two jurisdictions, Japan and the State of California in the US, selectively require extended back-up as a mitigation measure for extreme weather – earthquakes and wildfires, respectively. Four European countries (Belgium, Greece, Hungary and Ireland) mandate that operators mitigate security or resilience risks within their mobile networks, which could but does not necessarily include the provision of battery back-up. Only one country studied, Australia, offered government funding for the provision of battery back-up through its Mobile Network Hardening Program, which provides grant funding targeted to selected high risk sites. While it clearly values this lens of international comparison, Ofcom has also repeatedly referenced a relatively unique set of compounding circumstances in the UK that have created a heightened sense of urgency around mobile network resilience. It appears unlikely that any one international example of regulated power back-up standards can be particularly instructive for advancing further resilience obligations in the UK, which is already reflected in Ofcom’s more nuanced approach to outlining the range of possible objectives it could set within the broader context of mobile resilience.
