Know what the numbers mean.
Review the PHI model, the evidence behind it and the difference between a performance gap, a Project estimate and verified savings.
A model built for this hotel.
The PHI model compares actual energy and water use with efficient use for that hotel, its facilities, activity and weather.
Each hotel has its own model. Another hotel’s consumption does not become your model. Cost and carbon remain separate from the PHI score.
Read the score correctly.
PHI = (Actual − Best in class) ÷ Actual × 100. Lower is better. A negative value means use is below the model.
Actual use must be positive. Overall PHI is the equal mean of unrounded Energy and Water PHI. The product assigns the displayed band.
Keep three measures separate.
The performance cost gap prices a modelled difference. A Project estimate describes proposed work. Accepted verification establishes a realised saving.
These measures are never added together. Approval or completion alone establishes no saving and changes no PHI score.
Keep the evidence visible.
PHI is published monthly. Inputs, assumptions, confidence and coverage sit beside the result. Missing evidence remains visible.
Published corrections retain their reason and version history. Savings verification uses an agreed comparison method with relevant weather, activity and measurement coverage.
- Outperforming
- Best in class
- Good
- Needs attention
- Poor
- Not available
Data and assumptions
| Input | Basis | Value |
|---|---|---|
| Energy | Actual | 1,000,000 kWh |
| Water | Actual | 10,000 m³ |
| Assumption | Assumption | laundry kg / occupied room |
| Missing | Missing | Missing |
Correction history
Published v225.0
Meter 3 reallocated after the bill was reissued.
Superseded v127.2
A clearer next step for every hotel.
Bring your energy and water questions. Explore the findings, proposed work and evidence in a Cadae demo.