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Case Study: Delivering Measurable Energy Savings Through HVAC System Optimisation

HVAC system upgrades often miss the real performance issues. This case study shows how simulation-led optimisation reduced energy use and improved comfort—without replacing equipment.

The challenge: high energy bills despite ‘efficient’ equipment

A government office complex had undergone major HVAC upgrades in recent years. Efficient boilers had replaced aging plant, VFDs were added to pumps, and a new BMS provided basic visibility into operation.

Still, energy bills kept climbing. Comfort complaints from staff were consistent—some zones overheated, others never reached setpoint. The facility team had run out of conventional fixes.

Diagnosing the system with simulation

Using Hysopt, engineers created a digital twin of the existing system. The simulation didn’t just visualise layout—it showed real dynamic behaviour under varied conditions.

Key findings included:

  • Flow bypassing through inactive loops
  • Pressure zones that destabilised ΔT
  • Control sequences that caused unnecessary boiler cycling
  • Pumps operating outside their efficient range due to hydraulic imbalance

These inefficiencies weren’t visible in the BMS or detectable via manual audits—they only appeared when system interaction was modelled holistically.

Simulation-led optimisation—no new hardware needed

With full system visibility, the team was able to take targeted, effective action.

Pump settings were recalibrated to better match actual load, and valve authority was restored simply by adjusting pre-sets, without replacing any hardware.

Control logic was reprogrammed to reduce oversupply and stabilise return temperatures, while a heating night-setback strategy was implemented, simulated, and validated before activation.

No new plant or emitters were purchased. The result was a low-disruption and evidence-backed upgrade.

Results: energy and comfort gains that stuck

After 12 months of monitored performance:

  • Heating energy consumption dropped by 27%
  • Return temperatures fell by over 6°C—boosting boiler efficiency
  • Occupant complaints fell by more than 40%
  • Commissioning issues were eliminated during zoning updates
  • The payback period came in under 24 months

The simulation model remained in use as a live validation tool—supporting ongoing optimisation and maintenance planning.

Insight: sometimes the problem isn’t the equipment

This project succeeded because the team asked a better question—not “what needs replacing?” but “how is the system behaving?”

The answer came from simulation. With a clear picture of flow, temperature, and control interaction, they made smart changes that worked—and proved it with real data.

Want to see similar results?

You don’t always need new hardware to improve performance.

You need the right insight, applied at system level. Here’s everything you need.

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