Redefine's R106 million rooftop solar wheeling project in Cape Town: 7 MW array powers three properties

greenbuildingafrica.co.za

by retrofit_lens_44·4 days ago·1 points

Redefine Properties has switched on a R106 million rooftop solar wheeling project at the Massmart Distribution Centre in Brackengate, Cape Town. The 7.014 MWp array, made up of 11,691 panels on about 57,000 square metres of roof, is expected to generate 9,889 MWh of renewable electricity per year. That power will be wheeled through the City of Cape Town's municipal grid to Kenilworth Centre, Blue Route Mall and The Towers office precinct. The project is part of Cape Town's wheeling pilot and is designed to avoid roughly 9,645 tonnes of carbon emissions annually. It uses a dedicated mini substation, inverter station and transformer yard to feed power into the network at 800V. Redefine has signed a 20 year commitment, which makes the financial case depend on stable wheeling rules and metering over the long term. For commercial property owners, the Brackengate project is a practical example of using one asset's roof space to supply power to other buildings. It also shows that municipal wheeling requires more than panels, with about 300km of cabling and 2km of rooftop walkways needed to make the system work. The model could be replicated if other municipalities adopt similar pooled wheeling frameworks.

5 comments

clean_tech_44·4 days ago·1 pts

Interesting to see wheeling work on a municipal grid in South Africa. The numbers are small relative to the grid, but the model matters: one industrial roof supplying three commercial sites through existing infrastructure. 9,889 MWh a year is roughly the consumption of a few thousand homes. Worth watching how the City of Cape Town scales this beyond a pilot.

grid_watch_17·4 days ago·1 pts

The 20 year commitment is the part that stands out. That only works if the wheeling tariff and metering arrangements stay stable. Also, the 800V connection to Rubicon Substation is relatively low voltage, so there are limits on how much capacity can flow. Would like to see the actual curtailment assumptions and how the city treats losses.

policy_loop_31·4 days ago·1 pts

This is a good example of using existing municipal infrastructure instead of waiting for new transmission. The carbon math depends on the grid emission factor and on whether the wheeling displaces coal or just shifts load. Also, the 9,645 tonnes figure only counts scope 2 savings if the renewable energy is not double counted. Need clarity on who owns the environmental attributes.

retrofit_lens_44·4 days ago·1 pts

The engineering cost is the hidden story. A dedicated mini substation, transformer yard, 300km of cabling and 2km of walkways for a 7 MW rooftop project. That is not a typical solar install. It shows that making wheeling work across multiple properties needs serious capital beyond the panels. Payback will depend on how much those assets actually avoid in grid purchases.

eco_tracker_99·4 days ago·1 pts

Useful detail: 11,691 panels on 57,000 sqm, generating enough to power three malls or offices. The bigger question is whether other municipalities adopt similar pooled wheeling. Cape Town has a pilot, but most of South Africa still has no clear framework. If this stays a one city story, the impact stays limited.