Maintaining the ‘health’ of voltage and current

Estates and Facilities managers and their teams in NHS hospitals and other healthcare settings face major challenges. With the NHS committed to becoming the world’s first Net Zero national health service, numerous energy-saving measures must be implemented, with gas as an energy source increasingly being replaced by electricity.

Additionally, the growing use of electronic equipment is contributing to electrical pollution, placing the reliable operation of equipment under increasing strain.

Electrical energy supply in NHS hospitals

NHS hospitals have experienced a significant rise in the use of electronic medical devices over recent decades, with, for example, CT scanners, MRI scanners, X-ray machines, dialysis equipment, and surgical robots, now indispensable in healthcare. With more advanced devices being introduced, productivity is increasing, and hospital stays are being shortened. At the same time, the need for energy efficiency is becoming more pressing, with solutions such as solar panels, LED lighting, and frequency-controlled drives, being widely implemented.

However, these energy-saving devices and medical equipment also introduce pollution into the power grid, negatively affecting power quality (voltage and current quality). Compounding the issue, modern equipment is increasingly sensitive to the very pollution it generates. This has serious consequences for the stability of the electrical energy supply, in terms particularly of:

• Increased risk of system failures due to voltage dips and/or current peaks.
• Emergency power systems failing due to 
capacitive networks, harmonic pollution, and unbalanced loads.
• Higher maintenance costs and more frequent malfunctions due to increased network pollution from mechanical installations, medical equipment, LED lighting, and solar panels.
• Greater load on the neutral conductor due to unbalanced phases and network pollution.
• Increased transformer load caused by network pollution and asymmetric loading.
• Ever more stringent legal requirements regarding electrical energy quality and responsibilities.

Decreasing manageability of electrical energy systems

One major consequence of these trends is the decreasing manageability of electrical energy systems. Emergency power operations are failing, and voltage dips are causing diagnostic equipment failures, sometimes even leading to temporary department closures. The costs of poor power quality are often hidden within maintenance budgets, making them difficult to track.

Existing energy monitoring systems in NHS hospitals are typically linked to building management systems, and focus primarily on energy consumption. However, the ‘health’ of voltage and current is often overlooked. Electrical disturbances and power quality issues frequently go unrecorded, making it difficult to diagnose voltage failures. This is no longer acceptable for modern NHS healthcare institutions aiming for Net Zero.

Leveraging its experience in critical applications such as data centres and hospitals to ensure voltage and current availability under all conditions, fortop UK applies its unique chain of competencies: measuring, monitoring, and improving.

This chain of competencies enhances operational reliability, and optimises the utilisation of electrical installations, a process known as power optimisation.

• The four management aspects 
of electricity

Power optimisation is a continuous improvement process involving measurement, monitoring, and optimisation to prevent failures, reduce energy and maintenance costs, and minimise the impact of malfunctions. This process focuses on four key aspects (see Figure 1):

1. Energy Efficiency (Consumption)

Mandatory energy audits and increasingly stringent NHS and government regulations make continuous insight into energy flows essential. By visualising energy consumption, awareness and engagement in energy-saving measures increase, and their impact can be continuously assessed. Additionally, this approach enables accurate allocation of energy costs to different hospital departments and tenants. Monitoring power consumption across installations helps identify energy losses, standby consumption, and metering connection errors immediately.

2. Load (Current)

Facilities managers need a clear understanding of available capacity within the electrical system without requiring costly expansion. When switching to back-up generator operation, it is crucial to know how much power is available for connected equipment. Harmonic pollution, low power factor (cos-phi), and unbalanced loads, place additional stress on transformers and generators. Additionally, the dynamic behaviour of loads makes prediction challenging, necessitating insight into daily, weekly, and yearly load profiles.

3. Quality (Voltage Quality)

A ‘healthy’ voltage supply lowers maintenance costs, prevents failures, and conserves electrical energy. It also provides clarity and responsibility allocation, which is essential in liability cases following equipment failures. Voltage quality standards play a crucial role in determining whether medical equipment can be connected, and whether warranties apply.

4. Continuity (Sags, Swells, and Residual Currents)

Voltage dips and current peaks can cause failures in parts of the electrical installation. Timely alerts shorten downtime by enabling faster troubleshooting. By recording dips and peaks with a resolution of 50 microseconds, the root cause can be identified, and appropriate measures can be taken to mitigate negative impacts.

Integrating power quality into power monitoring systems

When integrating energy measurement systems for energy efficiency, it is essential to incorporate voltage and current quality into the monitoring concept.

• Three steps to lower consumption,
reduced maintenance costs,
and fewer failures

Power management is a continuous improvement process involving measurement, analysis, and optimisation, aiming to reduce energy consumption, lower maintenance costs, and minimise failure risks.

1. Continuous measurement with power analysers

To support continuous improvement, 24/7 measurement is essential to enable trend analysis, verification of energy savings, and real-time alerts for incidents. Fortop uses a standardised blueprint for an ‘installation-wide’ measurement system, assigning the most suitable measuring instrument at each level of the electrical installation, including Janitza measurement instruments with a resolution of 50 µs for precise voltage and current sampling (see Figures 4 and 5).

2. Continuous monitoring with gridXpert

To consolidate all measurement data into a single 
system, and translate it into actionable insights, fortop
UK has developed the gridXpert Healthcare Edition (see Figure 6). This system provides real-time and historical 
measurement data at a millisecond level. It integrates data from meters, switches, generators, and UPS systems into real-time alerts, visualisations, and reports. Its key features include:

• Alarm Manager: Immediate alerts for 
overloading, voltage failures, and power quality deviations, via SMS, email, BMS, or a dedicated smartphone app.
• Power Tree Function: This maps real-time and historical phase loads for the entire electrical 
system, identifying energy waste and optimising capacity.

The NHS should use power monitoring instead of just a simple building management system (BMS), because power monitoring provides detailed insights and control over energy usage, which is crucial for healthcare facilities. Building management systems can provide only basic energy data, and cannot offer the advanced insights into grid health, usage, and quality, that drive power monitoring forward.

A simple BMS controls building functions, but lacks deep energy analytics. Power monitoring adds precision, cost control, and reliability, making it a smarter choice for the NHS’s energy management strategy. This will lead to enhanced energy efficiency, cost savings, improved resilience and reliability, compliance and sustainability, and better, more informed, decision making and future planning.

This is not to say that PMS and BMS are exclusive solutions. In fact, many facilities are already 
equipped with a BMS and choose to expand on its capabilities by integrating with a new PMS. Issues arise only when facilities attempt to rely on a BMS to avoid using an PMS.

3. Improving power quality

Electronic devices distort current, generating 
harmonics that cause overheating of cables, 
transformers, and generators, leading to energy 
waste. Harmonic currents also pollute voltage, 
causing unstable operation, unexplained failures, 
and unnecessary energy losses.

The FPH Modular Hybrid Filters provide a comprehensive solution for power quality issues. These filters contain both active and passive components, allowing them to mitigate various power quality problems, including harmonics, supra-harmonics, resonances, and unbalanced phases. Key benefits include:

• Up to 30% more transformer capacity, and 50% more generator capacity, by filtering reactive power and harmonics.
• Up to 4% energy savings and CO2 reduction by reducing cable and transformer heating, and improving overall energy efficiency.
• Lower maintenance costs and protected equipment warranties by minimising voltage pollution.

Voltage dip prevention with stabilisation systems

Voltage stabilisation systems operate parallel to the load, mitigating short-term voltage dips without requiring full UPS systems. This prevents equipment failures and unwanted current peaks.

The team of technical specialists at fortop UK can guide NHS hospitals and healthcare facilities through all aspects of power management — from selecting the right meters, to commissioning and maintaining software and active compensation systems.