What monitoring actually finds
Every building has a bill it never questions. Monitoring is how you find out what is in it.
The overnight baseline
The first thing sub-metering shows is what a building draws when it is closed and empty. Almost nobody guesses this correctly.
Some of it is legitimate: refrigeration, security, servers, frost protection. The rest is plant nobody switched off, equipment on a timeclock set years ago, and heating running in an empty building.
It is the cheapest saving available because it costs nothing to fix. It is also the one a monthly bill can never reveal, because the bill sums the whole month into one number.
Equipment failing slowly
Most commercial equipment does not fail suddenly. A fridge with a going door seal draws a little more each week. A compressor with a dirty condenser works harder. A motor on a worn bearing pulls more current.
None of that shows in temperature or in output until it is far along. It shows in the draw almost immediately, which is why alarms on measured circuits catch failures weeks before anyone notices in the room.
Schedules that no longer match the business
Opening hours change. Shift patterns change. Timeclocks do not.
Monitoring shows equipment coming on hours before the first person arrives and running long after the last one leaves. This is usually the second-largest finding and the second-cheapest to fix.
The outlier site
For anyone running more than one building, the highest-value finding is comparison. Two shops of similar size and trade should use similar energy. When one uses appreciably more, that gap is a list of actions.
Without per-site measurement on the same basis, the difference disappears into a portfolio average.
Drift
This is the finding that justifies ongoing monitoring rather than a one-off audit. Settings get changed back. A contractor puts a schedule to manual and leaves it. A setpoint moves during a cold snap and stays.
Savings decay quietly unless somebody is still watching the numbers, which is what energy management is for.
Common questions
How much can energy monitoring save?
It varies by building type and by how well the site is already run. VisionGreen sees typical payback on monitoring installations of 1 to 3 years. One VisionGreen client site saved 10,518 kWh in its first six months of monitoring, avoiding 2.46 tonnes of CO2.
Is monitoring different from smart meters?
Yes. A smart meter measures the whole building at the incomer, usually in half-hour intervals. Circuit-level monitoring measures individual assets and areas every few seconds, which is what makes short cycling, equipment faults and schedule problems visible.
Do I need monitoring on every circuit?
No, and it is usually a waste of money. The circuits worth metering are the ones that are large, variable or prone to failure. In most buildings that is refrigeration, HVAC, compressed air, process equipment and the overall baseline.
Want this applied to your building?
Start with an energy audit. If you spend over ten thousand euro a year on energy, the SEAI grant covers most of the cost.