Downloadable public model
South African corporate PPA and wheeling model
A transparent representative workbook that separates the PPA energy price from losses, use-of-system charges, administration, balancing and residual grid supply before calculating buyer savings and generator returns.
Model viewer
Follow the commercial logic from meter to cash flow
The public workbook contains eight linked sheets. These panels show the core settlement, buyer and generator calculations.
Delivered-cost bridge
Year 1 all-in renewable cost
Total R1.45/kWh versus an illustrative avoided grid tariff of R1.85/kWh.
Energy allocation
Year 1 buyer settlement
- Buyer load
- 120.0 GWh
- Renewable delivered
- 96.0 GWh
- Residual grid supply
- 24.0 GWh
- Unmatched generator energy
- 7.0 GWh
| Metric | Year 1 | Year 5 | Year 10 | Year 15 |
|---|---|---|---|---|
| Gross generation | 110.0 GWh | 107.8 GWh | 105.1 GWh | 102.5 GWh |
| Energy after availability, losses and curtailment | 103.0 GWh | 101.0 GWh | 98.5 GWh | 96.0 GWh |
| Buyer load | 120.0 GWh | 124.9 GWh | 131.2 GWh | 137.9 GWh |
| Renewable energy delivered | 96.0 GWh | 99.9 GWh | 98.5 GWh | 96.0 GWh |
| Residual grid supply | 24.0 GWh | 25.0 GWh | 32.8 GWh | 41.9 GWh |
| Renewable share | 80.0% | 80.0% | 75.0% | 69.6% |
The declining renewable share later in the term demonstrates why a live case should use interval or monthly load matching, not only annual generation and consumption.
Year 1 cost bridge
| Grid-only baseline | R222.0m |
|---|---|
| PPA energy cost | R110.4m |
| Network and service charges | R28.8m |
| Residual grid cost | R44.4m |
| Total cost with wheeling | R183.6m |
| Buyer saving | R38.4m |
Buyer outputs
| Year 1 saving | 17.3% |
|---|---|
| Year 5 saving | 21.4% |
| Year 10 saving | 24.5% |
| Year 15 saving | 26.5% |
| 15-year savings NPV | R525.2m |
| Base buyer case | PASS |
| Metric | Year 1 | Year 5 | Year 10 | Year 15 |
|---|---|---|---|---|
| Delivered renewable energy | 96.0 GWh | 99.9 GWh | 98.5 GWh | 96.0 GWh |
| PPA tariff | R1.15/kWh | R1.40/kWh | R1.78/kWh | R2.28/kWh |
| Revenue | R110.4m | R139.6m | R175.6m | R218.6m |
| Total OPEX | R17.0m | R21.1m | R27.5m | R35.8m |
| EBITDA / unlevered cash flow | R93.4m | R118.5m | R148.1m | R182.8m |
The public workbook deliberately shows an unlevered generator case. A transaction model would add development spend, construction drawdown, debt, tax, working capital, reserves and distributions.
| Scenario | Year 1 saving | Saving % | Generator IRR | Commercial reading |
|---|---|---|---|---|
| Base | R38.4m | 17.3% | 11.91% | Benefits both parties in the public case |
| PPA +10% | R27.4m | 12.3% | 13.79% | Value shifts from buyer to generator |
| Grid tariff -10% | R20.6m | 10.3% | 11.91% | Lower avoided cost narrows savings |
| Delivered energy -10% | R37.1m | 16.7% | 10.25% | Generator return is more exposed |
| Network charges +20% | R32.6m | 14.7% | 11.91% | Buyer savings absorb network risk |
| Buyer downside | R3.7m | 1.9% | 12.09% | Buyer economics nearly lose commercial rationale while value shifts toward the generator |
| Buyer upside | R64.6m | 26.4% | 11.35% | Lower PPA and higher grid baseline |
Transaction map
The model covers the interfaces that determine delivered cost
A corporate PPA is only one part of the structure. The model makes the additional commercial interfaces visible.
Public basis
Official framework used to structure the representative case
The public model reflects the structure described in current official material: time-of-use matching, generator and buyer agreements, use-of-system and administration charges, loss-adjusted credits, connection requirements and monthly settlement. All prices and financial outputs in the workbook remain illustrative.
Live mandate
What a transaction-specific wheeling case adds
- Half-hourly or monthly buyer load, generation and profile-matching analysis.
- Actual Eskom or municipality-specific network tariffs, loss factors and administration fees.
- Connection, use-of-system, account amendment, metering and settlement agreement review.
- Volume, shape, take-or-pay, shortfall, surplus energy and imbalance allocation.
- Curtailment, deemed energy, grid outage, change-in-law and termination-payment scenarios.
- Buyer and generator credit support, security deposits, guarantees and payment timelines.
- Generator project-finance model, buyer savings model and a reconciled commercial term sheet.
Public Excel file
Review the settlement and savings formulas directly
The file is a synthetic representative model. It is not a legal opinion, approved network quotation or confirmation of available wheeling capacity.
Corporate power analysis
Need a PPA or wheeling case run on the actual buyer and generator data?
Share the load data, generation assumptions, tariff schedules, proposed contract and decision deadline.