The electricity grid is not as reliable as it once was, with the transition to renewable power posing new risks to both reliability and the cost of power. The grid is operating with greater uncertainty, variability and a tighter supply-demand balance. This is driven by increased renewable generation, an aging thermal generation fleet, and unexpected retirement of capacity which is increasing the risk of forced outages (AEMO).
Now more than ever, there is a stronger need for hospitals to ensure they have working redundancy measures in place and the confidence they can continue to support patients in the event of a grid trip or failure. Hospitals across Australia are raising their standard of emergency preparation by using an innovative new approach to testing their backup power infrastructure – participating in a Virtual Power Plant (VPP).
A VPP is a collection of distributed energy assets (backup generators, batteries, flexible loads) that work together to provide additional dispatchable capacity to the grid. They are called on when large power stations suddenly fail, when demand is extremely high relative to supply, or when climatic events threaten grid stability.
Participating in a VPP provides a compelling new way for hospitals to enhance their emergency preparedness by testing backup power systems under conditions which simulate true emergency situations. This achieves a new benchmark for best practice testing standards.
Hospitals typically participate by switching to backup generation when required, which can be done safely and without interrupting hospital services. By temporarily reducing demand during critical grid events, hospitals can earn a significant new revenue stream. This can be reinvested into backup power infrastructure upgrades, further enhancing system reliability. Where hospitals require an infrastructure upgrade to achieve uninterrupted load transfer, in many cases this new revenue stream will quickly pay off the investment, which can be externally financed.
Routine testing practices have shortfalls
Common testing practices often fail to fully simulate the response required during a grid power failure.
While load bank testing can exercise the generator under load, it doesn’t test the full load transfer sequence using automatic transfer switches and ancillary circuit breakers, and loads are not representative of actual hospital operations.
Another practice, black start testing, tests all system components, however it’s not often done under true emergency conditions such as during a hot summer afternoon when an outage is most likely to occur. This approach doesn’t account for the effects of elevated ambient temperatures, increased building loads, and generator de-rating on system performance.
By participating in our VPP, hospitals can thoroughly test their backup power systems whilst having the safety net of grid power to switch back to should any potential issues be identified.
