Optima vs EnergyPlus, RETScreen & Excel
They are all good tools, for different jobs. The real question is: which job do you need done?
| Optima | EnergyPlus / HAP / TRACE | RETScreen | Excel | |
|---|---|---|---|---|
| Question the tool answers | Is replacing this unit worth it? | How should the building’s system be designed and sized? | Is this clean-energy project viable? | Whatever you manage to model yourself |
| Typical user | Contractor, distributor, engineering firm, building manager | Building simulation engineer | Energy project analyst | Everyone, at the cost of hours of manual work |
| Time for a replacement business case | ≈ 5 minutes | Days (full building model required) | Hours | Hours, redone for every project |
| Weather | Real hourly data, any location | Hourly weather files (TMY) | Monthly averages | Rarely included |
| Equipment performance curves (COP vs T°) | Built in, defrost included | Possible, modeled by hand | Simplified | Manual, rarely done |
| Actual energy tariffs | Extracted automatically from the bill | Entered manually | Entered manually | Entered manually |
| Deliverable | Client-ready PDF report | Technical simulation output | Project analysis report | Your spreadsheet |
| Learning curve | Low | High | Medium | Low, but inconsistent results |
The right tool for the right job
Use EnergyPlus, HAP or TRACE…
to design a new system, size equipment or run code compliance. They are excellent engineering tools, but building a full building model just to justify a unit replacement takes days.
Use RETScreen…
to screen clean-energy projects at large (solar, wind, efficiency). Its strength is breadth, not depth: on the HVAC side it works with monthly averages rather than hourly equipment simulation.
Use Excel…
for a quick back-of-the-envelope estimate. But without hourly weather, COP curves or consistency between reps, a spreadsheet remains an approximation that is hard to defend in front of a client.
Use Optima…
when the question is economic: replacing a gas RTU with a heat pump, retrofitting an aging system, comparing two candidates. Hour-by-hour simulation, real tariffs, professional report, in about 5 minutes.