In recent years, the global demand for power has risen sharply.
And our expectation to be continually plugged into the latest technology is as evident in industry and healthcare as it is in our home lives, with technologically-advanced equipment increasingly reliant on power to operate.
Conversely, in the last few months, the change in our lifestyles and living and working patterns driven by the Coronavirus pandemic have seen our usage patterns fluctuate and the demand on the grid reduce.
To mitigate the risk to life, and the knock-on effect of having to reschedule appointments in an already-overstretched public service, hospital power systems usually take a multi-phased approach to backing up their power supply
Hand in hand with these changes in demand, the UK’s energy mix is going through a transition from fossil fuel-generated electricity to an increased prevalence of renewable sources.
Combine these factors and the National Grid is faced with a challenge when it comes to balancing demand and supply - a situation which can lead to unexpected outages.
Needless to say, with people’s lives in their hands, hospital trusts are well aware of the impact of a break in mission-critical power - from the more-obvious effect on lighting, heating and operational infrastructure, such as lifts and computer systems; to critical lifesaving equipment in theatres and intensive care units.
To mitigate the risk to life, and the knock-on effect of having to reschedule appointments in an already-overstretched public service, hospital power systems usually take a multi-phased approach to backing up their power supply.
A mixture of local battery power and uninterruptible power supply (UPS) systems will handle the immediate risk and prevent critical machines from shutting down.
While the risks of downtime vary from site to site, one thing remains constant - interruptions in power supply have the potential to cause operational chaos
This short-term fail-safe is backed-up by generator systems, which are designed to be operational within minutes and have the capacity to take over from the emergency batteries and power buildings and machinery over a longer period.
Generators and the role of testing
Usually installed at build phase, standby generators are a common solution to provide back-up power if the standard electricity supply is interrupted.
They are known for being robust and reliable, offering contractors and facilities managers the reassurance that they’ll do the job and kick in if the worst happens.
However, just like any other internal combustion engine, lubrication, cooling systems, fuel system and electrics all need to be tested to ensure faultless operation.
Lifting, moving and transporting sensitive equipment, as well as varying on-site conditions such as temperature and humidity, make it absolutely critical that back-up power systems are tested in-situ in actual site conditions after being installed and on an ongoing basis thereafter.
Load banks are used to test, support, or protect a critical back-up power source and ensure it is working should an outage occur
Testing back-up power
While the risks of downtime vary from site to site, one thing remains constant - interruptions in power supply have the potential to cause operational chaos.
Wherever a generator is installed, there is also a need for a load bank - a device used to create an electrical load which imitates the operational or ‘real’ load that a generator would use under normal operational conditions.
Load banks are used to test, support, or protect a critical back-up power source and ensure it is working optimally should an outage occur.
Load banks are used to test, support, or protect a critical back-up power source and ensure it is working optimally should an outage occur
Ideally, all generators should be tested annually for real-world emergency conditions using a resistive-reactive 0.8pf load bank. This provides a picture of how well an entire system will withstand changes in load pattern while experiencing the level of power that would typically be encountered under real operational conditions.
The inductive loads used in resistive/reactive testing will show how a system will cope with a voltage drop in its regulator. This is particularly important for hospitals, where multiple generators might be operated in parallel.
In this type of application, a problem with one generator could prevent other generators from working as they should. With fuel, exhaust and cooling systems also untested, as well as the potential for embedded moisture, an untested system becomes extremely high risk.
The business case for load banks
The importance of testing is being recognised in many new-build facilities, with the installation of load banks often being specified at the design stage rather than being added retrospectively.
The potential cost of power failures in the healthcare sector is unfathomable, putting an overstretched system under additional pressure and causing a very real threat to life
The cost of purchasing a load bank is typically a fraction of the cost of the system which it supports, with rental options negating the need for capital expenditure altogether.
Finances aside, the potential cost of power failures in the healthcare sector is unfathomable, putting an overstretched system under additional pressure and causing a very real threat to life.
With this in mind, those specifying, commissioning or managing these sites can ill afford to overlook the critical role of load banks when it comes to ensuring a stable, consistent/ and constant flow of power.
