Report from Cape Town

Ranald Lawrence (SSoA), 29 March 2015

Temperatures in Cape Town reached 42°C earlier this month, the highest since records began over 100 years ago. With rising temperatures come new and familiar challenges. March’s peak temperatures were accompanied by wildfires ignited in Muizenberg, Table Mountain National Park, which burned through 15,000 acres of land and claimed the life of one of the helicopter pilots sent to tackle the flames. Wildfires are nothing new in Cape Town – and the fires that accompany the summer months are part of the natural process of the regeneration cycle of the native fynbos which covers the Cape peninsula – but this fire was the worst seen in decades, and the City of Cape Town Fire Service and local volunteers did well to limit the damage to only 13 properties. At one stage, with flames licking the edge of the farm, the historical collection of furniture and art at Groot Constantia, the oldest wine estate in South Africa, was removed for safe-keeping.

1. Wildfire on Table Mountain, by Warren Rohner. This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.

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This is the latest and perhaps the most acute example of a changing climate and the tourist and agriculture-led economy of the Western Cape coming into conflict, but there are also plenty of longer-term examples of systematic conflict. The wine cellars upon which the wine industry of South Africa depends need to be maintained at a long-term average temperature of 13°C. Gradual seasonal changes in temperature are acceptable, but rapid diurnal fluctuations damage wine irrevocably. Daily mean temperatures in Constantia fluctuate between 11.9°C in July and 20.4°C in January and February, with average highs of 26.5°C in February.

While the original estates depended on the massive stone construction of the Cape Dutch vernacular for storage of wine, production was expanded rapidly in the latter half of the twentieth century with investment in affordable air conditioning systems and reliable energy infrastructure. According to the 2015 statistics, the wine industry now employs directly or indirectly some 300,000 people in the Western Cape, contributing R36.1 billion (£2 billion) to the GDP of the region (the contribution of the industry to GDP has increased by 10% per annum for over a decade).

2. Groot Constantia Estate

2However, it is not only the seasonal fires that threaten the vineyards. Rolling blackouts, euphemistically referred to as ‘load shedding’, have been increasing in frequency since the 1990s. The state electricity provider Eskom were prevented from investing in new power infrastructure for most of the 1990s in an effort to deregulate the industry; however no private investors came forward to build new power plants. Rolling blackouts were introduced in 2007 as demand outstripped supply for the first time. In 2008, multiple trips across the power network forced production to cease in major gold and platinum mines across the country. Despite construction of new power stations and the re-commissioning of mothballed coal power plants together with the introduction of diesel-powered generation at peak times, power cuts have persisted. In November 2014, Eksom could only provide 24GW of electricity, 4GW short of demand and a full 22GW short of a stated operational capacity of 46GW. This shortfall was blamed on shortages of diesel, water reserves in hydroelectric facilities, and unplanned maintenance. Depending on the severity of the rolling blackouts, the economic cost in terms of lost productivity is estimated at R20-80 billion (£1.1 to £4.5 billion) per month.

3. Arnot Power Station, Middelburg, by Gerhard Roux. This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.

3Typically the rolling power outages hit in the late afternoons at the hottest times of the year. They are still relatively infrequent, and short enough not to cause significant damage to wine production at the moment, but increasingly wine producers (and those living in the wealthier suburbs) are investing in microgeneration (normally in the form of diesel generators, but PV is increasingly popular) to guarantee supplies. But are there lessons that might be learned from vernacular approaches to wine production and storage that could not only benefit the industry today but also reduce energy consumption more generally?

Gabriël Fagan is a native South African architect, born in 1925, who received the SAIA (South African Institute of Architects) Award of Merit for his design of the Klein Constantia Winery of 1986. Subtlety derived from the vernacular details of South Africa, but reinterpreted in a modern-regionalist language not unsimilar to the work of Geoffrey Bawa, Alvaro Siza or even Sverre Fehn, his work displays a deep and intuitive grasp of the environmental properties of the old Cape Dutch houses; thick thermally massive walls, small openings, and large volumes of space to dissipate internal heat upwards. The cellars of the Vineyard are partially submerged into the ground to take advantage of the diurnal temperature stability of the earth, minimising the need for additional cooling during the day.

4a/b. Klein Constantia Winery

4a4bThese lessons are also revealed in the climatically conscious domestic work of Kevin Fellingham’s practice based in Cape Town. House J, built for his parents in Simon’s Town to the south of the city, looks north and east over False Bay, stepping up the hillside at the top of the old naval town to take advantage of the strong breezes that blow along the slopes that make up the ‘Cape of Storms’. Concrete ‘eyebrows’ shade the sliding glass doors and screens that dissolve the corners of the building, extending the inside, outside, onto a series of concrete balconies and terraces, the main balcony off the living room being shaded in turn by a steel pergola and further cooled by the evaporative action of the sun on a small pool naturally cleaned by filtering reeds and other aquatic plants.

5. House J, Simon’s Town

5a5bKevin is currently also converting a historic property in the Bo-Kaap area of the city into an urban dwelling reinterpreting its historic use as a house with a tripartite plan, with studio and office left and right of the main entrance, and living and dining spaces to the rear. A neighbouring property makes use of a small internal courtyard to naturally cool the interior through passive downdraught ventilation, while the bedrooms reach up the roof to access to a terrace overlooking Table Mountain, and create a natural airpath for the purging of warm air from the inside.

6. Design detail for a house in Bo-Kaap

6Both properties are currently being monitored to record outdoor and internal temperatures and to quantify the thermal effects of the natural ventilation strategies that have been adopted.

Kevin combines his practice activities with teaching at the University of Cape Town School of Architecture, Planning and Informatics, which exemplifies this approach of learning from the vernacular traditions of the past in order to build architecture resilient to both the natural and manmade challenges of the future. At an urban scale, urbanisation and resource depletion will present more challenges to the already creaking infrastructure of the city in years ahead, including increased pollution and shortages of clean water as well as electricity. M’Arch students at the School in Cape Town are encouraged to respond to these macro-scale environmental challenges in their thesis projects, which are then integrated into design solutions at a building scale which address the specific architectural and social questions that they pose.

7. M’Arch Interim Presentations at the University of Cape Town

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