Plumbing Africa August 2019 | Page 34

32 ENVIRONMENT AND ENERGY Solar thermal systems go big in South Africa “The level of sophistication of these ST systems has expanded rapidly and today, these systems provide hot water for large residential institutions, such as hotels, hospitals, schools, student residences and even districts. African Solar Thermal Training & Demonstration Initiative), a regional project focused on capacity building and the demonstration of solar thermal solutions in the SADC region. It is funded by the Austrian Development Agency (ADA) and the OPEC Fund for International Development (OFID). “South Africa recently made it into the top 20 largest ST systems in the world with the installation of two SOLTRAIN projects – a district heating plant for Wits University residences in Parktown Johannesburg and a solar process heat plant for the Klein Karoo International (KKI) tannery in Oudtshoorn. Both will save millions in electricity costs over the lifetime of the plants. “In order to apply the knowledge gained during SOLTRAIN training courses implemented across the SADC region, 326 demonstration systems were installed in ‘Solar Thermal Flagship Districts’ to pilot and demonstrate the different solar thermal applications available. The total collector area of these systems is 4 621m², corresponding to an installed capacity of 3.2 megawatt thermal (MWth). “The first of its kind, the Wits Junction district heating project, combines solar, co-generation and gas heating technologies, servicing 1 103 students in 14 student residence buildings with hot water from one centralised hot water plant room. “There is an average consumption of 94 000ℓ of hot water per day. Peak demand is in the morning, averaging 30% of daily consumption, with a maximum demand of 28 200ℓ an hour. The system supplies the entire hot water demand, including kitchens, laundry, cleaning and other domestic uses.” SOLTRAIN builds capacity through demo systems “SANEDI is a critical partner in SOLTRAIN, (Southern www.plumbingafrica.co.za @plumbingonline @plumbingonline “The size of these demonstration systems ranges from small systems with a 2m² collector area and a 150ℓ hot water tank for single family houses in social housing areas to the above large-scale systems, with almost 600m² collector area and 60 000ℓ storage tanks for industrial applications and district heating. “The annual solar yield of all 326 solar thermal systems is 3 534MWh, which corresponds to electricity savings of 3 887MWh per annum and 1 222 tons of avoided CO 2 . The avoided electricity cost corresponds to R9.9-million, based on City of Cape Town tariffs in 2019 of 222.39c/kWh plus VAT, which equals 255.75c/kWh.” @PlumbingAfricaOnline August 2019 Volume 25 I Number 6