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SSEG Program Assessment

Quantitative Assessment on the Benefit Proposition of Residential Nano-Grid Deployments

3 kWp PV Solar10 kWh BESSGrid-Tied System
Year 1 Savings
R 4.45 Million

Per 10,000 unit deployment

Year 10 Savings
R 73.90 Million

16.6x Year 1 savings

10-Year Cumulative
R 338.34 Million

Total bulk cost reduction

Peak Demand Reduction
50 MW

33.3% evening peak reduction

How Nano-Grid Reduces Municipal Bulk Supply Costs
Strategic cost reduction through distributed energy resources and demand management

Solar Generation Offset

Each 3 kWp PV system generates 4,500 kWh annually, directly offsetting grid purchases during sun hours (07:00-17:00).

45 GWh/year

at 10,000 unit scale (62.8% of total 71.6 GWh municipal consumption)

Peak Demand Shaving

10 kWh BESS discharges during evening peak (18:00-20:00), reducing maximum demand and saving R 44.32/kVA monthly.

R 2,659/unit/year

in demand charge savings

Tariff Arbitrage

Eskom escalates at 9% vs Nano-Grid at 5%. This 4% differential compounds over time, creating accelerating savings.

16.6% CAGR

savings growth rate

10,000 Unit Fleet Deployment Impact
Projected annual and cumulative savings from full-scale Nano-Grid deployment

Total PV Capacity

30 MWp

Total BESS Capacity

100 MWh

Annual Generation

45 GWh

62.8% of 71.6 GWh total

Instantaneous Peak Shaving

50 MW

33.3% of evening peak (17:00-21:00)

The Fused Nano-Grid Solution: 10 kWh BESS + 3 kWp PV
Understanding how the specific component blend creates optimal distributed energy resource utilization

3 kWp Photovoltaic System

  • Generates 4,500 kWh annually (17% capacity factor)
  • Operating hours: 07:00-17:00, peak generation 10:00-14:00
  • Excess energy exported to grid (grid-tied system)

10 kWh Battery Energy Storage System

  • 5 kW continuous discharge power
  • Charges during day (PV excess), discharges 18:00-20:00
  • Reduces peak demand by 5 kVA per unit

Grid-Tied DER Optimization

As a grid-tied system, ALL excess alternative generated energy is exported directly into the municipal grid. This ensures optimal Distributed Energy Resource (DER) utilization with zero energy wastage, maximizing the return on each Nano-Grid deployment while supporting grid stability.

Energy Cost Convergence Over Time

While Year 1 shows a premium for Nano-Grid PV Component energy, the 4% annual escalation differential causes crossover by Year 8.

Note: Year 8 marks the crossover point where the Nano-Grid PV Component becomes cheaper than Eskom supply

Strategic Value Proposition

Immediate Benefits

  • Positive cash flow from Day 1 (R 37.12/unit/month)
  • Demand charge savings of R 2,659.20 per unit annually
  • Reduced grid dependency during critical evening peak

Long-term Value

  • 16.6% CAGR savings growth over 10 years
  • Long-term hedge against Eskom tariff escalation
  • R 338.34M cumulative savings at 10,000 unit scale