South Africa’s 2nd most populous city, Cape Town has repeatedly been selected as the world’s most attractive tourist destination. Cape Town’s natural beauty includes the scenic Table Mountain, Victoria and Albert waterfront development, the close proximity to the vineyards at Paarl and Stellenbosch, Kirstenbosch Gardens and Caledon Gardens. There is much undeveloped potential that could be developed in the future to make the Cape Town area even more appealing to tourists. Cape Town is also served by a major seaport and a world class international airport. Railway links connect the Greater Cape Town area to numerous mining resources.
While the Gauteng and Johannesburg area is South Africa’s most populous metropolis, that inland region is located at a great distance from the sea and its future expanded supply of potable water will depend on water resources development in several neighbouring countries. Gauteng – Johannesburg area does NOT have the option to desalinate seawater. Industries and groups that depend on overland transportation between Gauteng – Johannesburg and Durban have complained about lack of capacity to move massive numbers of containers by rail and also by road. A railway link between Port of Maputo container terminal and Johannesburg is being developed.
Cape Town area has several advantages over Gauteng – Johannesburg:
1 – Cape Town is a seaport with direct access to low-cost maritime transportation. Most of the world’s international trade moves in containers carried by ships and ships incur far lower transportation per container per unit-of-distance that railway and truck transport. Cape Town’s coastal location reduces the transportation cost of importing and exporting goods-in-containers, compared to large inland locations.
1a – Expansion of a Brazilian container port will result in much larger container ships sailing between South America and Asia, at much lower per container transportation costs. These ships will sail via South Africa and could be built to a much larger size than container ships that sail through the Suez Canal. The Brazilian initiative should prompt Transnet to develop or allow for the development of a transshipment port at or near Cape Town that could berth the super-size container ships and offer lower per container transportation costs between South Africa and Asian and Brazilian super ports.
2 - Close access to the ocean provides Cape Town with a resource to desalinate to produce potable water. A major thermal desalination plant may be built adjacent to Koeberg nuclear thermal power station, using the exhaust heat from the power station to produce water vapour in low-pressure ‘boilers’. Seawater from the cold northbound Benguela Current would be used to condense potable water from the low grade steam.
3 – During summer, portion of the cold water of the northbound Benguela Ocean Current that flows along the western coast of the Greater Cape Town Area can be applied to decreasing the energy consumption required to main cool temperatures inside large buildings located to the sea front. During winter, heat pumps may extract heat from seawater in False Bay to provide interior to buildings located within close proximity to False Bay.
4 – In recent years, Cape Town area has experiences increased humidity in the atmosphere. The cold seawater from the Benguela Ocean Current can be applied to closed-loop heat exchangers that could be applied to extract potable water from humid summer air, while using minimal energy. There have been major advances in the development of water-from-air technology and Cape Town could become the site of a mega-scale version of installations of that technology.
4a – The increase in wind-blown summer humidity allows for the installation of fog-fences across several mountain valleys in the Greater Cape Town Area. Fine-mesh fences made from woven stainless steel would be corrosion resistant as well as UV-resistant, allowing many years of operation compared to woven fabric mesh that is vulnerable to damage caused by prolonged exposure to solar UV-radiation. Provincial government may need to negotiate with national government to allow for installation of mesh fences in mountain areas across the Greater Cape Town area.
5 – Cape Town has endured alternating seasons of drought and excessive amounts of rainfall. During periods when Cape Town’s water storage dams are filled to capacity, there remains much potential to store massive amounts potable water underground in aquifers across the Greater Cape Flats area. There is also massive potential across the Cape Flats for hundreds of private homeowners and owners of commercial buildings to install rain barrels and water storage tanks on their properties, including underground tanks.
6 – Sea waves regularly pound the Greater Cape Town Area’s coastal region. New developments in ocean wave conversion technology could be applied along the coast of the Cape area. Provincial government officials would need to negotiate with National Government officials to allow private entrepreneurs to install ocean wave conversion technology around the coast of the Cape area, to generate electric power for private use.
7 – Sea wave technology could also sustain the operation of installations of reverse-osmosis seawater desalination technology, to provide potable water to numerous coastal locations around the Greater Cape Town Area.
8 – A powerful ocean current moves westbound off the southern coast of the Western Cape and northbound off the western coast of the Cape Peninsula and Western Cape. Provincial government may need to negotiate with National government to allow private entrepreneurs to install ‘underwater windmills’ that can extract some energy from the ocean currents. The ‘underwater windmills’ could drive either electrical generators OR corrosion-resistant water pumps that pump water under pressure to reverse-osmosis desalination installations at coastal locations.
8a – During winter, the ‘underwater windmills’ may also drive coastal heat pump installations that extract heat from seawater and transfer the heat into nearby buildings. During summer, the heat pumps may switch to reverse mode and transfer heat from nearby buildings into the seawater or into underground geothermal reservoirs of water-saturated porous rock.
9 – Geologists advise that an extensive layer of porous rock occurs under the Cape Peninsula. Given the close proximity to the ocean, it is possible that this deep porous rock may be saturated with seawater and offering the equivalent of a geothermal battery. During summer, heat collected by solar reflectors installed on mountain areas may be transferred underground into seasonal geothermal storage. During winter, the stored heat may be used to provide interior heating for buildings, the result of a cubic unit of seawater having some 3500-times the heat capacity of the identical cubic unit of air at sea level atmospheric pressure.
9a – The temperature of deep-level, seasonally stored geothermal energy under the Cape Peninsula could be raised to just under the boiling point of water. During winter, the temperature difference between the geothermal heat and the seawater to the west of the Cape Peninsula could sustain several months of the operation of organic Rankine cycle (ORC) engines that could generate electric power for local seasonal use. South Africa typically consumes more electricity during winter than during summer as people seek to use electric power to heat the interior of buildings.
10 – Weather conditions frequently cause cyclones to occur above warm ocean water at numerous locations around the world. Some small cyclones pick up droplets of seawater that are propelled upward to higher elevations, where the seawater evaporates into cloud and sea salt falls back to the sea. Prevailing winds would push the cloud toward land and over coastal mountains where precipitation would likely occur. It may become possible to artificially produce water spouts at select locations, such as to the southeast of the southern entrance of False Bay and south of the Kogelberg and Hottentots Holland Mountains. During summer, prevailing winds would carry the additional humidity north toward the watershed areas of Steenbras Dam and Theewaterskloof Dam, where fog fences could assist in extracting water from humid air.
11 – The Port of Saldanha Bay can berth deep-keel ore carrier ships that carry iron ore to overseas markets. A heavy-haul railway line for ore trains connects that port to the mining town of Sishen, located west of Kimberley. Ore is compact while manufactured products occupy many times to volume. The availability of iron ore and close proximity to the Port of Cape Town would allow for the development of a steel products manufacturing industry located north of Cape Town, that exports to overseas markets. Barges pushed by tugs could move iron ore from Saldanha Bay to coastal locations between that bay and Cape Town, while the barges could also move large volume items from factory to Port of Cape Town.
12 – The ocean currents carry massive volumes of sand offshore near the Greater Cape Town area. Sand contains silicon that is used in a wide variety of manufactured items that include electronic components (diodes), telecommunications components (transistors), information processing equipment (silicon chips), high temperature ceramics (silicon carbide and silicon nitride) and silicone rubbers. There is scope to develop related manufacturing companies for such items in the Greater Cape Town area.
13 – A substantial volume of oceanic vegetation grows in the sea off the South African coast as is evident from the amount of sea kelp that ocean waves regularly deposit on beaches around the Greater Cape Town area. Much of this kelp contains minerals such as magnesium and iodine and is ground up to make plant fertilizer. An estimated dozen varieties of oceanic vegetation is edible (for people). Crisps made from sea kelp have become a popular snack in several Asian countries. Recent innovations in the cultivation of oceanic vegetation involve the use of buoys and trays and can be applied offshore across the Greater Cape Town area. The technology may even be applied to increase the volume of shellfish that may be commercially raised off the Greater Cape Town coastal region.
14 – The ‘boomslang’ suspended walkway at Kirstenbosch Gardens is popular with locals and with visitors. Internationally, there are several suspended walkways at tourist attractions. Cape Town could install suspended walkways along cliff sides at Table Mountain, such as between Platteklip Gorge and just below the upper cable car station. The popularity of the cable car could justify the construction of a 2nd route that could borrow precedent from overseas ski resorts that feature intermediate towers that suspend the cables at intermediate points. Such technology could bring the lower cable car station closer to Kloof Nek Road or closer to the city centre.
14a – Waterslides and roller coaster installations are popular tourist attractions. At Cape Town, it may be possible to install a waterslide using pumped seawater at Victoria and Alfred (V & A) waterfront area. An extended ride roller coaster may also be possible along Cape Town’s mountains, perhaps with the terminus at V & A waterfront area and extended above road level toward Signal Hill. An overhead cable car system with intermediate towers may also connect between V & A and Signal Hill, perhaps extending to Lion’s Head.
Cape Town is home to University of Cape Town, University of the Western Cape and Cape Peninsula University of Technology. Interested students may also enroll at UNISA and advance their studies via correspondence. There have been improvements made to international telecommunications and internet connections that allow students in the Cape Town area to gain access to educational programs from overseas. Cape Town’s future economy will increasingly come to depend on the development of the human – intellectual capital that includes the entrepreneurial mindset that is capable of developing practical new ideas in science and technology that is based on readily available resources from within South Africa. Such an endeavour will require the active participation and involvement of several thousand such people whose intellectual output would contribute to creating Cape Town area’s future economy.
Cape Town has several unique natural resources that enhance the Greater Cape Town area’s potential for future economic development. The willingness of Transnet to allow for development of a transshipment terminal for mega-size container ships that will soon sail the South America – Asia route via South Africa, would greatly enhance future economic development prospects for the Greater Cape Town area.
About the Author:
Harry Valentine was born at Cape Town and attended primary and secondary school in Cape Town’s former District-6 area. He holds a degree in engineering and undertook post graduate studies and research in transportation as well as economics.