What is the difference between a walkthrough audit and an investment-grade audit?+
A walkthrough or screening audit uses bills, a site visit and engineering judgement to indicate where the opportunity is likely to be, and is appropriate when you are deciding whether to look further. An investment-grade audit adds measurement, detailed modelling, vendor-level costing and risk assessment so the numbers can support a capital decision or financing. Choosing the deeper study first is only worthwhile once you know roughly where the consumption sits.
How much energy saving is realistically available?+
It depends entirely on the facility, its age, how it is operated and what has already been done. The honest answer before an audit is that nobody knows, and any consultant quoting a percentage in advance is quoting an industry average rather than your site. What is consistently true is that a meaningful share of the opportunity is usually operational, meaning schedules, setpoints, controls and maintenance, and therefore available without capital expenditure.
Do we need submetering before an audit is useful?+
No, an audit is useful without it, but submetering changes what can be proven. Without it, consumption is allocated using engineering estimates and run hours, which is adequate for prioritising but weak for verifying savings. Where a facility intends to manage energy continuously, pursue ISO 50001, or verify performance contracts, we normally specify metering as one of the first measures rather than a later refinement.
What does ISO 50001 actually require?+
ISO 50001 requires a management system: an energy policy, a documented energy review that identifies significant energy uses, an energy baseline and performance indicators, objectives and action plans, operational controls, competence and awareness arrangements, monitoring and measurement, internal audit, and management review. The technical analysis sits inside that structure. Organisations sometimes commission an audit expecting it to deliver certification; the audit is an input to the energy review, not the system itself.
How are savings verified after implementation?+
Through a measurement and verification plan agreed before implementation, which defines the baseline, the measurement boundary, the normalising variables, the data to be collected and how routine and non-routine adjustments will be handled. The protocols in common use, such as IPMVP, provide recognised options for whole-facility and isolated-system approaches. Agreeing the method afterwards almost always produces a dispute, because both parties then choose the baseline that suits them.
How does energy management relate to carbon reporting?+
Energy data is the primary input to Scope 1 and Scope 2 emissions. If consumption cannot be attributed reliably, the emissions figures inherit that weakness, which matters where disclosure is assured or where product-level figures are required for export reporting. Building the metering and data discipline once serves energy cost control, ISO 50001 and carbon disclosure together, rather than maintaining three parallel and mutually inconsistent datasets.
Should energy performance be addressed at design stage?+
Yes, and it is materially cheaper there. Envelope, orientation, system selection, sizing, zoning, metering provision and control strategy are largely fixed at design and expensive to change later. Reviewing design intent, specifications and control philosophy before procurement typically costs a fraction of retrofitting the same performance into a completed building or plant, and it also avoids the oversizing that drives poor part-load efficiency.
