The 10% Improvement That Cannot Be Proven
At a chilled-ready-meal factory you are conducting a stage 2 certification audit. The site consumes 84 GWh of natural gas and 38 GWh of electricity a year. Its EnPI is 'electricity kWh per tonne of product', and the energy baseline is 218 kWh/t set in 2019. The energy manager claims a 10% energy performance improvement, reporting 196 kWh/t for the last 12 months, although production fell 18% and the product mix shifted from ready meals to soups, which need longer cooking. In March the team retroactively adjusted the 2021 baseline by subtracting a fixed 12 kWh/t 'product mix correction'; no method, data set or approval is recorded. The 2022 energy review lists ovens, ammonia refrigeration and boilers as significant energy uses. Compressed air is not listed, although sub-metering shows it uses 19% of electricity and a 2023 leak survey identified leaks that were never repaired. Gas is excluded from the EnPI.
1. The energy manager argues that the 10% improvement is proven by the EnPI. As lead auditor, how do you test this claim and what evidence do you require before accepting it?
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Start by decomposing the claim. A fall in kWh per tonne can be caused by lower production, a different product mix, or fixed loads (refrigeration, compressed air, lighting) spread over fewer tonnes. The 18% production drop and the shift to longer-cooking soups are plausible confounders, so intensity alone does not demonstrate energy performance improvement.
Check the indicator's coverage. Gas is 84 GWh of a 122 GWh total, roughly 69% of site energy, and it is absent from the EnPI. An indicator that ignores the dominant energy source cannot determine energy performance as required by 6.4. Recompute using total energy (convert gas and electricity to a common unit, e.g. GJ) per tonne and per product family.
Test the baseline adjustment. 6.5 permits adjustment when there are relevant changes, but the adjustment must be based on a documented, repeatable method and retained as documented information. Ask for the regression model, the independent variables (tonnage, product mix, degree days), the data period, the statistical basis, the approval, and how the 12 kWh/t figure was derived. A retroactive flat correction applied to 2021 without a record is not verifiable.
Evidence to sample: three years of monthly gas and electricity meter data reconciled to invoices; production records by product; recipe and process changes; degree-day data; sub-metering; the EnPI definition and data collection plan; the baseline adjustment record; management review decisions on performance.
Conclusion: the 10% claim is not supported as presented. State in the report what could and could not be verified rather than accepting or dismissing the figure.
2. Formulate the nonconformities you would raise, with clause references and a proposed classification (major or minor). Justify each classification.
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NC 1 - major - 6.4 and 6.6. The EnPI excludes natural gas, about 69% of site energy, and the data collection plan does not provide gas data for performance evaluation. Evidence: the EnPI definition, monthly performance reports, gas invoices. This is major because the indicator is structurally incapable of demonstrating energy performance; the failure is in the design of the measurement process, not an isolated lapse.
NC 2 - major - 6.5. The 2021 baseline was adjusted retroactively by a fixed 12 kWh/t with no documented method, data set or approval. Evidence: the adjustment spreadsheet, absence of a procedure, interviews. Major because the baseline is the reference against which all performance claims are judged, and this adjustment cannot be verified or repeated.
NC 3 - major - 6.3. Compressed air, at 19% of electricity, is not identified as a significant energy use despite sub-metering and a leak survey. The energy review has not been updated to reflect current data. Justification: the energy review drives SEU prioritisation, objectives and operational control; omitting a fifth of electricity use undermines planning. An auditor could argue minor if compressed air were already controlled elsewhere, but here the identified leaks were not actioned, which reinforces the systemic gap.
NC 4 - minor - 8.1. Identified compressed-air leaks were not repaired or included in an action plan. Minor if the leak programme is otherwise operating and this is an isolated control failure; it would become major if no operational control exists at all.
Record objective evidence for each, avoid duplicating the same root cause across NCs, and note that NCs 1 and 2 may be reported together if the root cause is a single ineffective performance-measurement process.
3. What would you tell the certification body's technical reviewer about whether the organization has demonstrated continual improvement? Distinguish 'continual improvement' from 'energy performance improvement'.
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Distinguish the two concepts. Continual improvement (10.3) is the recurring process by which the EnMS enhances overall energy performance; energy performance improvement is a measurable result related to energy efficiency or energy use. An organization can maintain a conforming EnMS that is continually improving without achieving a fixed percentage reduction, and certification does not certify a performance level.
However, the EnMS must be capable of demonstrating results. 9.1.1 requires evaluation of energy performance against the baseline and EnPIs, and 6.4/6.5 must make that evaluation meaningful. Here the indicator omits most energy, the baseline adjustment is unverifiable, and an SEU is missing from the energy review. Therefore the organization cannot show whether performance improved, and the claim of 10% should not appear in the audit report as verified.
Advice to the reviewer: the major nonconformities affect the core performance-evaluation process, so the auditor cannot conclude that the EnMS is effective. Certification should not be recommended until correction and corrective action are implemented and their effectiveness verified. If the certification body later issues a certificate, the report must be clear that the 10% figure was not validated, so the certificate is not read as an endorsement of that claim.
Also examine 9.3: management review accepted the 10% claim without challenge. That is relevant evidence about whether top management is reviewing energy performance effectively, and it should be explored in the closing meeting.