Calculator Inputs
Example Data Table
| Scenario | Capacity (kW) | Sun Hours | Days | Downtime (hrs) | Tariff | Estimated Loss |
|---|---|---|---|---|---|---|
| Roof Array Phase 1 | 250 | 5.1 | 30 | 10 | 0.11 | 842.60 |
| Warehouse Canopy | 400 | 5.8 | 30 | 16 | 0.13 | 1,834.20 |
| Ground Mount Block B | 750 | 6.0 | 30 | 21 | 0.15 | 3,296.80 |
| Temporary Site Office | 80 | 4.7 | 30 | 6 | 0.12 | 216.40 |
Formula Used
Gross Potential Energy = Capacity × Sun Hours × Days
Adjusted Expected Energy = Gross Potential Energy × Performance Ratio × (1 − Degradation) × (1 − Curtailment)
Downtime Ratio = Total Downtime ÷ Daylight Hours in Period
Energy Lost = Adjusted Expected Energy × Downtime Ratio
Revenue Loss = Energy Lost × Tariff
Total Financial Loss = Revenue Loss + Maintenance Impact
This method links production exposure to actual solar operating time, making the estimate useful for construction sites, phased installations, and maintenance planning.
How to Use This Calculator
- Enter the project name for reporting clarity.
- Provide installed capacity and average daily sun hours.
- Set the analysis period in days.
- Enter performance ratio, degradation, and curtailment assumptions.
- Input planned and unplanned downtime hours.
- Add tariff and maintenance cost values.
- Set recovery efficiency and target availability.
- Press calculate to view loss, availability, and graph outputs.
Why This Calculator Matters
Solar downtime can affect commissioning plans, temporary power strategies, project cash flow, and maintenance scheduling. This calculator helps construction teams estimate lost production, outage cost, and operational impact using one practical workflow.
The output supports daily reporting, budget checks, contractor reviews, warranty discussions, and decisions on whether recovery actions are financially justified.
FAQs
1. What does solar downtime loss mean?
It is the energy and money lost when a solar system cannot produce normally during available daylight hours.
2. Does planned downtime count as a loss?
Yes. Planned shutdowns still reduce production, so they should be measured for budgeting, maintenance scheduling, and contractor coordination.
3. Why use sun hours instead of full clock hours?
Solar production mainly depends on daylight generation windows. Using sun hours gives a more realistic exposure estimate than a full 24 hour day.
4. What is performance ratio?
Performance ratio reflects real operating efficiency after system losses. It helps convert ideal generation into a more practical expected output.
5. What does recovery efficiency represent?
It estimates the share of lost production that can be partially regained through cleanup, faster repair, or improved scheduling after an outage.
6. Can I use this for monthly and yearly reviews?
Yes. Enter the correct number of days for the period you want, and the calculator will scale the energy and cost estimate.
7. Is maintenance cost always part of total loss?
Not always, but including it gives a broader downtime picture, especially when repairs, callouts, or labor hours rise during failures.
8. Can this help compare outage scenarios?
Yes. Change downtime hours, tariff, or recovery values to compare financial exposure across maintenance plans or failure cases.