The City of Cape Town has been focusing on how it can save energy in its operations in order to reduce its environmental impact, improve resource efficiency, and avoid excessive electricity costs – especially in light of Eskom’s tariff increases and South Africa’s electricity supply shortages.
The City’s own operations (street and traffic lights, buildings, pumping, fleet etc.) are responsible for 1,4% of all energy consumption and 2,2% of all electricity consumption in Cape Town. Considering that the City is just one organisation, this is a large amount of energy.
“Recognising the role that it has to play in leading by example and helping to promote energy efficiency in Cape Town, the City has committed to reducing its energy consumption by 10%. A number of projects and programmes are already underway, and the savings that are being realised are helping to motivate for further projects to be initiated,” said the City’s Mayoral Committee Member for Economic, Environmental and Spatial Planning, Alderman Belinda Walker.
Buildings account for about 16% of the City’s electricity consumption. Making administrative buildings more energy efficient not only reduces costs, but also often improves the quality of the working environment.
Four large administrative buildings in Plumstead, Ottery, Fezeka and Durbanville have been retrofitted with energy efficient technology, through a performance contract with an energy services company. These retrofits, completed in 2011 and funded by the Danish International Development Agency, saw the installation of efficient lighting and lighting controls, power factor correction units, solar water heaters, and air conditioning thermostat controllers. Through this project, the City is guaranteed to see savings of 338MWh every year across the four buildings. This amounts to a saving of 17% of the energy consumed in these buildings.
The success of this project has meant that the City has expanded this programme to a further 14 buildings, including libraries, clinics, administrative buildings and workshops. This new project is funded by the Department of Energy’s Energy Efficiency and Demand Side Management(EEDSM) programme. The audit for these buildings has been completed, and the City aims to commence installation of efficient lighting technologies in September 2012. The savings on this project will be guaranteed by the energy services company, and the City will save 547MWh each year through these lighting retrofits alone. This is a saving of 54% of energy used on lighting, and further opportunities for retrofits of other technologies will be identified to save even more.
The Cape Town Civic Centre was audited in 2011, and there are a number of interventions which have been proposed. A detailed redesign of the lighting will be taking place this year and, from the audit results, it is estimated that 3 800MWh could be saved each year on the lighting alone. The lifts, heating, ventilation and air conditioning system are being upgraded and sub-meters will be installed in this 23-storey building to monitor the impact of these interventions. This project is funded from the City’s budget.
Behaviour change interventions
While technical retrofits do a lot to save electricity in buildings, the behaviour and habits of occupants in these buildings has an impact on consumption. Much effort has been put into changing behaviour in a number of City-owned buildings, particularly where retrofits have taken place. Workshops, exhibitions and the use of resources like posters, flyers and the City’s Smart Living Handbook have been used to educate facilities managers, building office staff and the public who use the services offered in the buildings, on how to save electricity through their actions – both in the workplace and at home. Workshops are currently being held in the 14 buildings receiving lighting retrofits and in the Cape Town Civic Centre.
Street lighting and traffic lighting
Street lights and traffic lights make up approximately 37% of all electricity consumed by the City. This provides an enormous opportunity to save. As such, funding from the EEDSM programme and the Electricity Services Department has been allocated for retrofitting Cape Town’s street and traffic lights.
The City of Cape Town is on track to have retrofitted all of its traffic lights with Light Emitting Diode (LED) technologies by September 2012. Retrofits of the 1 378 traffic intersections in the city will save 11 818MWh per year.
Upon completion of all of the projects outline above (where the savings can be easily calculated or monitored), the City will be saving 22 747MWh (or 22,7 million kWh) of electricity in total per year and reducing its carbon footprint by 22 747 tonnes of CO2.