How load bank testing prevents pharmaceutical manufacturing downtime

According to research from UK-based technology and managed-services provider, IDS-INDATA, “UK and European manufacturers are projected to lose more than £80 billion to downtime in 2025.”

Unplanned downtime remains one of manufacturing’s greatest risks. While less frequent than in sectors such as general industrial manufacturing or food processing, in pharmaceutical production it carries far more severe consequences.

Modern therapies, including monoclonal antibodies, vaccines, advanced cell and gene therapies, are developed through laboratory-scale processes before being scaled for commercial manufacture. This transition involves tightly regulated, highly complex operations where every stage, from cell growth and purification to formulation and packaging, must be precisely controlled.

Even brief interruptions can compromise product quality. Power fluctuations during bioreactor runs can destroy weeks of cell culture. Lapses in airflow or pressure on aseptic fill-finish lines can trigger requalification, while interruptions to chromatography or lyophilisation may render entire batches unusable. Deviations can also result in non-compliance with GMP or MHRA requirements, leading to batch rejection.

While less frequent than in sectors such as general industrial manufacturing or food processing, in pharmaceutical production [downtime] carries far more severe consequences

Downtime delays batch release and disrupts supply chains, creating bottlenecks that affect hospitals, pharmacies, and clinics. For patients dependent on time-critical therapies, such delays can directly impact treatment schedules and outcomes.

The financial implications are equally significant. Downtime events in pharmaceutical manufacturing often last eight hours or more, with costs estimated at £5–10 million per incident. Conservative projections suggest UK-wide downtime losses for the sector could approach £1 billion in 2025 [1]. Given these stakes, maintaining uninterrupted power is essential. 

Backing up power

Even in well-managed facilities, power outages remain an unavoidable risk. To protect sensitive manufacturing processes, pharmaceutical plants rely on carefully engineered backup power systems combining standby generators, uninterruptible power supplies (UPS) and battery storage and redundancy.

In practice, generators provide sustained electricity during extended outages, keeping essential manufacturing systems operational until grid power is restored. UPS systems deliver instantaneous power during the critical seconds required for generators to start and synchronise, preventing interruption to sensitive processes. Battery storage further stabilises supply by absorbing voltage dips, extending UPS runtime or supporting particularly critical circuits.

Pharmaceutical plants rely on carefully engineered backup power systems combining standby generators, uninterruptible power supplies (UPS) and battery storage and redundancy

Redundancy is also designed into these systems to ensure continuity if a single component fails. This may include dual generators, parallel UPS configurations or segregated power distribution circuits isolating essential equipment. Additional considerations, such as selective coordination, fault-clearing times and compliance with IEC 60364 or BS 7671, help ensure system stability under abnormal grid conditions.

While these arrangements provide multiple layers of protection, even well-designed backup power systems can fail without proper validation.

Hidden vulnerabilities

Over time, backup systems can develop weaknesses that only become apparent under real operating stress. UPS systems are particularly susceptible to gradual degradation. As valve-regulated lead-acid or lithium-ion batteries age, internal resistance increases and discharge capacity declines. This can result in voltage sag or brief interruptions capable of tripping sensitive PLCs, environmental controls or aseptic systems — threatening batch integrity even when primary equipment remains functional.

Generators present different risks. Emergency loads in pharmaceutical facilities are often low and stable, meaning generators frequently operate below rated capacity during routine testing. Chronic underloading can lead to wet stacking, where unburned fuel accumulates in the exhaust system. During an actual outage, this may cause slow load acceptance, frequency instability or voltage drops affecting motors that drive bioreactors, pumps or centrifuges.

Ageing transfer switches, harmonics, corroded connections or poorly integrated upgrades can introduce resistance or distortion. Systems may pass inspections yet fail under full load, making proactive, high-fidelity testing essential. As a result, systems may pass routine inspections yet fail during sustained or full-load operation, making proactive, high-fidelity testing essential.

Testing systems

Load bank testing provides pharmaceutical manufacturers with a controlled, measurable way to replicate the electrical loads and stresses backup power systems would experience during a real outage. During testing, electrical load is applied to generators or UPS systems to simulate full facility demand or critical sub-system loads. Engineers can then assess voltage and frequency stability, step-load response, transfer times, thermal behaviour, fuel consumption and sustained performance.

This approach reveals issues such as wet stacking, UPS voltage sag, overheating cables or slow transfer switches that low-load testing cannot detect. Different load bank types allow accurate simulation of real operating conditions. Resistive load banks apply steady-state loads reflecting baseline demand, while reactive load banks replicate equipment with variable power factors. Dynamic load banks simulate rapid load changes such as motor starts, inrush currents and transient surges typical of pharmaceutical processes. 

Because simulated loads cannot be routed into live facilities, load banks safely absorb and dissipate generated energy using high-capacity ballast elements. Advanced programmable systems, such as Digiloa, can reproduce complex load profiles that mirror real plant behaviour, transforming load bank testing into a predictive tool for modelling realistic outage scenarios.

Unplanned downtime may be unavoidable, but its impact is not. Prevention remains the most effective safeguard. Load bank testing gives manufacturers confidence that backup power will perform, protecting therapies and ensuring medicines reach patients.

Andrew Keith is division director of load bank manufacturer Power Prove

Pic: UK Power Network

[1] https://idsindata.co.uk/manufacturing-downtime-costs-and-forecasting/