An impressive green home with a solar power system fully sponsored by Rubicon has won the My Clean Green Home design competition for sustainability. The competition is an initiative of the City of Cape Town (CoCT) and the Green Building Council of South Africa (GBCSA).

The home, designed by Team Mahali – consisting of recent graduates and young African professionals – competed against 17 other teams to create the net zero energy house. The modular house was made from two shipping containers, recycled pallet wood, and other upcycled and locally available materials.

Dubbed the “Mahali Hub’, the house incorporates rainwater harvesting, solar power generation, energy-efficient appliances, passive cooling, and a food garden. It has been exhibited to the public in various locations across Cape Town to demonstrate how sustainable energy, water, waste, and food systems function in practice.

The client’s requirements

When Team Mahali built the Mahali Hub, team member Natheera Ravat asked Rubicon if it could assist with solar power for the house.

The house needed to have an off-grid system that was also able to connect to a grid. This meant that the system needed to include a 3kW hybrid inverter that could use multiple power sources including battery, PV, and grid power, to supply a load.

 

The competition required the house to have a 1.1kWh back-up battery. However, Team Mahali opted to go for two 2.4kWh battery back-up so that the house would be able to run on it for longer if necessary.

All equipment used needed to comply with the CoCT’s regulations.

The solution

Team Mahali and Rubicon had several meetings with the CoCT to ensure that the equipment would comply with the city’s requirements.

Rubicon supplied and sponsored the entire power system for the Mahali Hub, except the mounting structure for the solar panels. This is because Team Mahali built the solar panels into the timber frame of the house.

Rubicon project lead, Travis Hatt, said: “I chose products that would best showcase Rubicon’s offering, comply with the city’s regulations, and be as cost-effective as possible.”

Hybrid inverter: Rubicon supplied a 3.6kW GoodWe single phase hybrid inverter. It chose this product, not only because of its high quality, but also because it complied with the CoCT’s requirements. During the exhibition, the Mahali Hub operates completely off-grid. But the house will be donated once the exhibition is over and needs to be able to connect to grid power. The GoodWe inverter makes this possible.

Solar panels: Eleven 295W Canadian Solar PV panels were provided. Hatt says that Canadian Solar is one of the best PV panel brands available in South Africa. These panels  are A grade which means they have no defects and are highly efficient. They are also tier one, which means that they are made by a large manufacturer, who is trustworthy and has good bankability.

Battery: Rubicon supplied two Synapse 2.4kWH batteries and the locally manufactured Synapse Slimline wall mounted enclosure in which to house the batteries.

Rubicon also sponsored and supplied all the smaller, balance of system components including the DC board, DB board, surge protectors, cables, crimps, fuses, and connectors.

Client feedback

Ravat raved about the service and equipment that Team Mahali received from Rubicon. She also emphasised the importance that a project like this has on reducing our carbon footprint.

“Rubicon fully came on board and grabbed this project by the horns,” she said. “They made a massive contribution, and I don’t think we would’ve been able to get the house up and running if it hadn’t been for them. They said ‘whatever you need, we’ll sort you out’. That helped tremendously because we didn’t have to approach different people to try fund the project.”

“Rubicon even did the design for us. Usually, we’d have to do the calculations to see how many breakers and such things we need, but they did all of that for us.”

“Everything runs perfectly. We could power up whatever we wanted to and the system supplied power more than what we needed for the competition.”

“The solution Rubicon supplied is an affordable, workable solution. The main thing is that it’s a turn-key solution. Everything you require is in one package, which makes implementation easy.”