Solar Chapel Cluster, Franschhoek South Africa
Solar Chapel at the HoldenManz Wine Estate, Franschhoek, Cape Town. The project utilizes the same solar panel technology used on the farm to clad the expanding wedding chapel's roof structure. The vertiginous mountains within the estate are reflected in the beton brut primary structure off which the concentrator Fresnel lenses, solar panels and holographic filters are suspended. The concentrator photovoltaics arrangement uses an angular configuration similar to that of a butterfly’s wing receiving more exposure to solar rays affording maximum efficiency for electrical output. The frame expands and contracts enabling a further rearrangement of this concentrator photovoltaic cluster. The concentrator lenses use fewer solar cells to harness solar energy, they can be programmed to follow the sun in tandem as it moves across the sky taking full advantage of available sunlight, the sliding steel frames onto which they are supported allow for more movement and maximum exposure. The main problem we are facing is to cool the concentrator photovoltaics, high concentration ratios introduce a heat problem, when solar radiation is concentrated so is the amount of heat produced this reduces cell efficiencies, higher temperatures also threaten the long-term stability of solar cells, therefore, the solar cells must be kept cool in a concentrator system, requiring sophisticated heat sync cooling designs, in this case the vineyards irrigation system.
The chapel sits within the vineyard amongst an array of existing solar screens, with the help of the holographic panels it also concentrates and intensifies the solar energy which can be stored and accessed as and when required. The chapel is used for religious fellowship and is a free standing structure epitomising the duality of the monumental context and the process of wine making.
Concentrator photovoltaics (CPV)
A CPV system uses mirrors and lenses to concentrate sunlight, the Solar Chapel concentrated Fresnel lenses capture the solar energy shining on a fairly large area then focus that energy onto a smaller area, where the solar cell is located. Concentrators increase the electrical energy output by 50%.