Project snapshot: 500kWp rooftop solar PV + 1MWh LFP BESS · Epping Industria, Cape Town · Commissioned Q3 2024 · RTO structure via SOCO CAPITAL
The Challenge
Our client operates a 12,000m² cold storage and logistics facility in Epping Industria, Cape Town. With ammonia refrigeration running 24/7 and a peak demand of approximately 820kVA, the facility sits on a Megaflex tariff with significant peak-period energy and demand charges.
The business faced two compounding pressures heading into 2024:
- Load-shedding exposure: Stage 4–6 load-shedding was causing 4–8 hours of daily outages, requiring the facility to run diesel generators at a cost of R18–22/kWh — more than three times the Eskom Megaflex peak rate. Product temperature excursions during extended outages created food safety compliance risk.
- Escalating grid costs: Monthly electricity spend had increased from R480,000 to R680,000 over three years — a 42% increase — with no change in throughput volumes.
The facility already had two 500kVA diesel generators, but running them continuously was financially unsustainable and operationally disruptive. The management team needed a permanent solution that did not require capital deployment from a business already managing tight margins.
The Solution
SOCO ENERGY proposed and designed a hybrid solar + BESS system optimised for the facility's Megaflex tariff structure and load profile:
Solar PV — 500kWp
1,250 × 400Wp monocrystalline bifacial panels installed across the facility's north-facing warehouse roof sections. The system was designed to maximise Standard-period generation (10:00–18:00) when the tariff is highest and the cold storage loads are at their peak. Average modelled annual yield: 780 MWh.
Battery Energy Storage — 1MWh LFP
A 1MWh lithium iron phosphate battery system (4 × 250kWh containerised units) with a 500kW inverter. The dispatch strategy was programmed for three simultaneous functions:
- Peak demand shaving: Discharge during the morning (07:00–10:00) and evening (18:00–20:00) Eskom Peak periods to suppress measured demand and reduce Network Demand Charges
- Load-shedding backup: Reserve 400kWh capacity as a no-break backup, sufficient for 45–60 minutes of critical refrigeration load during grid outages before the generators auto-start
- Off-Peak charging: Charge from grid during Off-Peak hours (22:00–06:00) at R0.92/kWh to discharge during Peak hours at R7.40/kWh — R6.48/kWh arbitrage margin
Financing Structure
The full system (solar + BESS + installation + monitoring) was financed via SOCO CAPITAL's Rent-to-Own product over a 60-month term. The monthly RTO payment was set at 65% of the client's average monthly electricity saving — ensuring positive cashflow from month one.
Results (First 6 Months of Operation)
Load-shedding resilience
During the Stage 4 and Stage 6 events in May–June 2024, the facility experienced zero product temperature excursions. The BESS provided seamless transition to backup power ahead of generator start — eliminating the 8–12 second gap that previously caused refrigeration control system resets.
Demand charge reduction
Network Demand Charges reduced by an average of R62,000/month — accounting for 25% of the total saving — through consistent BESS dispatch during Peak demand windows.
Diesel savings
Generator runtime reduced by 94% compared to the pre-installation baseline. Diesel spend dropped from an average of R85,000/month to under R5,000/month.
Client Comment
"We went from a situation where load-shedding was an existential risk to our cold chain compliance to one where we barely notice it. The financial case was compelling — but the operational peace of mind was the real win."
— Operations Director, Epping Cold Storage Facility