Section 6 · Business Plan
Technical Design & Engineering
The PV system configuration, grid-connection strategy and the Phase 2 battery energy storage design for the 100 MW solar plant.
6.1 System Configuration
| Parameter | Specification | Rationale |
| Nominal Capacity (AC) | 100 MW | Optimal for REIPPPP procurement |
| Installed Capacity (DC) | 130 MW | DC/AC ratio of 1.30 for yield optimisation |
| Module Technology | Mono PERC Bifacial | Tier 1 bankable, 25-year warranty |
| Module Rating | 580–620 Wp | Latest generation, high efficiency |
| Number of Modules | ~210,000–225,000 | Based on selected module wattage |
| Tracking System | Single-axis tracker | 18–25% yield uplift vs fixed-tilt |
| Inverter Architecture | Central + String hybrid | Site-specific optimisation |
| Grid Connection | 132 kV (or 400 kV) | Per Eskom cost estimate letter |
| On-site Substation | Dedicated 33/132 kV | Step-up transformation |
| Capacity Factor (P50) | 27.4% | Single-axis tracker, Northern Cape resource |
| Annual Generation (P50) | 240 GWh | Net of losses and degradation |
| Module Degradation | 0.4%/year | Year 1: 2%, thereafter 0.4%/year |
| System Availability | ≥98% | Contractual O&M guarantee |
| Project Life | 25–30 years | PPA term + residual asset life |
Table 3: System Configuration Summary
6.2 Grid Connection Strategy
Grid connection is a critical path item for any utility-scale solar
project in South Africa and has been identified as the primary
constraint for project deployment in recent REIPPPP bid windows.
Solstice Energy has proactively engaged with Eskom and the National
Transmission Company of South Africa (NTCSA) to secure a grid connection
cost estimate letter and confirm available capacity at the target
substation. The grid connection infrastructure includes a dedicated
33/132 kV step-up transformer and switchyard within the project fence, a
transmission line connecting the project substation to the nearest Eskom
point of common coupling, and protection, metering, and SCADA systems
compliant with the South African Grid Code.
6.3 Battery Energy Storage
(Phase 2)
In recognition of the evolving market preference for dispatchable
renewable energy, as evidenced by REIPPPP BW8’s 4-hour storage mandate
on 40% of capacity, the project design incorporates provisions for a 50
MW / 200 MWh battery energy storage system (BESS) as a Phase 2
expansion. The BESS will provide peak shifting, grid stability services,
and ancillary services revenue, enhancing the project’s value
proposition to off-takers and grid operators. Battery storage costs have
declined by approximately 35% in the past two years, and the Company
will evaluate the optimal timing for BESS deployment based on technology
cost trajectories and regulatory incentives.
Confidential — this business plan is provided to prospective investors and lenders for evaluation purposes only and may not be reproduced or distributed without the written consent of Solstice Energy (Pty) Ltd.