How utility-controlled connectivity improves SAIDI, SAIFI, CAIDI, and MAIFI
With private LTE/5G, connectivity becomes utility-controlled, resilient, low-latency, and wide-area, rather than depending on patchy public networks or a disconnected mix of radio systems. This fundamental shift in how field devices, substation equipment and operational systems communicate has a direct and measurable impact on the reliability metrics that utilities and regulators track most closely.
The four key reliability KPIs — SAIDI, SAIFI, CAIDI, and MAIFI — each benefit from the improved speed, coverage, and determinism that private LTE/5G delivers. The sections below explain the mechanism behind each improvement, with a summary reference table at the end.
SAIDI — System Average Interruption Duration Index
SAIDI measures the average total duration of interruptions experienced by each customer over a given period. It falls when faults are detected faster and service is restored sooner.
Private LTE/5G enables near real-time reporting from field devices across the distribution network. Reclosers, sectionalizers, substation equipment, smart meters, and fault indicators can all communicate continuously with the control room, allowing operators to pinpoint the faulted section quickly and isolate it before crews are dispatched. Less time searching means less time without power.
| SAIDI — System Average Interruption Duration Index
Goes down because faults are found and isolated faster. |
| – Near real-time telemetry from reclosers, sectionalizers, and fault indicators |
| – Faster fault location reduces the search time before crew dispatch |
| – Automated isolation limits the number of customers affected and shortens outage duration |
| – Smart meter data provides granular visibility of the fault boundary |
SAIFI — System Average Interruption Frequency Index
SAIFI measures how often, on average, each customer experiences a sustained interruption. It improves when utilities intervene before faults develop into full outages.
Private LTE/5G supports the dense, always-on sensor connectivity needed to detect warning signs early. Connected sensors can identify overheating assets, vegetation-related risk, abnormal voltage levels, and unstable feeders before these conditions escalate into sustained outages. With reliable backhaul, predictive and preventative maintenance programmes become more effective across the entire network.
| SAIFI — System Average Interruption Frequency Index
Goes down because threats are detected and resolved before they cause outages. |
| – Continuous sensor monitoring detects overheating, vegetation encroachment, and abnormal voltage |
| – Earlier intervention prevents conditions from escalating into sustained interruptions |
| – Supports automation and fast protection responses that limit fault propagation |
| – Enables smarter, data-driven preventative maintenance scheduling |
CAIDI — Customer Average Interruption Duration Index
CAIDI measures the average time taken to restore service after a sustained interruption. It is where private LTE/5G delivers some of its strongest operational value, because reliable connectivity is the foundation of effective restoration.
Once an outage occurs, every stage of restoration — SCADA and distribution automation, field crew coordination, remote switching, and final confirmation — benefits from a low-latency, high-reliability communications layer that does not depend on congested public networks.
| CAIDI — Customer Average Interruption Duration Index
Improves because each stage of restoration is faster and better coordinated. |
| – Real-time SCADA and distribution automation reduce manual switching steps |
| – Live video and data feeds from field crews improve situational awareness for dispatchers |
| – Better dispatch decisions reduce wasted travel and redundant crew movements |
| – Remote switching capabilities allow sections to be re-energised without physical crew attendance |
| – Faster confirmation that supply has actually been restored, closing the loop reliably |
MAIFI — Momentary Average Interruption Frequency Index
MAIFI tracks brief interruptions — typically under five minutes — that often go unnoticed by regulators but have a real impact on sensitive loads, industrial customers, and overall power quality. These are frequently caused by unnecessary or poorly coordinated protection operations.
Private LTE/5G improves the precision of communication between relays, reclosers, and control systems. Better-coordinated protection schemes reduce unnecessary trips and reclose operations, cutting the number of momentary interruptions that customers experience without compromising the integrity of fault protection.
| MAIFI — Momentary Average Interruption Frequency Index
Can improve because protection and switching devices are better coordinated. |
| – Low-latency signalling between relays, reclosers, and control systems enables tighter coordination |
| – Reduces unnecessary tripping and reclose operations driven by poor communications timing |
| – Supports adaptive protection schemes that respond more accurately to actual fault conditions |
| – Fewer unnecessary brief interruptions for customers on sensitive or industrial feeders |
Summary Reference
The table below summarises the mechanism through which private LTE/LTE/5G improves each reliability KPI.
| KPI | How Private LTE/LTE/5G Improves It |
| SAIDI | Faster fault detection & isolation via real-time field device reporting |
| SAIFI | Earlier intervention from predictive, sensor-driven threat detection |
| CAIDI | Reduced restoration time through SCADA, remote switching & live crew comms |
| MAIFI | Fewer momentary interruptions via coordinated protection & switching |
Regulatory Penalties for Poor Performance
The KPIs described in this document are not simply internal benchmarks. In most regulated markets, they are tied directly to financial incentive mechanisms that reward outperformance and penalise underperformance. The scale of these penalties makes the business case for reliability-improving technology, including private LTE/5G, materially significant.