Logistics yards run on diesel. Forklifts, gensets, yard lighting, and the office air conditioning — all of it on fuel when the grid is weak. This yard, on the road between Lahore and the dry port at Multan, sees two grid outages a day on average in the summer. The owner wanted a PV-charged yard with no genset during the workday.
We built a single containerised system. Inside the container: a 100 kW PV inverter, a 50 kW bidirectional PCS, a 200 kWh LiFePO4 rack, and an EV charging bay rated at 60 kW DC. The container sits next to the office block. The PV array is on the warehouse roof, about 80 m of DC cable away. The yard lighting and the office load ride the battery. The EV charger pulls off the same bus when a truck is parked.
How it is controlled
The container runs on three modes, selected by a local PLC: solar-following, peak-cut, and island. Solar-following is the default when the grid is up and the battery is more than 30% full. Peak-cut kicks in when the office load steps the meter above the contracted kVA. Island mode runs everything — the PV, the load and the EV charger — off the battery alone, capped at the PCS rating.
The PLC is ours (an off-the-shelf unit we configure in the factory) and the local control panel was wired by the customer’s electrical contractor on site. We sent a wiring diagram and a one-page commissioning checklist. The contractor finished the install in four days, and we joined by video for an hour on the final day.
Why a single container
Three reasons. First, customs: the container goes through Pakistan customs as one line item, not three, which compresses the duty paperwork. Second, install time: the truck backs up, the crane sets it down, the cables from the PV and the office get bolted to the external terminals, and the system is on. Third, warranty: if a card fails we send a single replacement unit, the customer pulls it out, and we send the spare.
For similar containerised optical-storage-charging systems for weak-grid sites, contact: 58298175@qq.com / +86-181-5931-0123.
