Browsing by Author "Pickering, Mark"

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    Electrification financing and tariffs: international literature review
    (1993) Eberhard, Anton; Mountain, Bruce; Pickering, Mark; van Horen, Clive
    This report was commissioned by the National Electrification Forum (NELF}. It is a review of international experience in electricity pricing, funding and financial management. The purpose of the report is to assess how these issues have affected electrification programmes in developing countries and to draw conclusions which will assist NELF in establishing appropriate electricity pricing and financing policies for South Africa. A successful electrification programme which enables widened access to electricity is ultimately dependent on the creation and maintenance of a financially viable electricity distribution industry. Financial viability is, in tum, crucially dependent on appropriate pricing and financing policies and financial management practices. The report is based on an extensive review of international literature. The review of electricity pricing commences with a discussion on pricing policies, the principles of economic efficiency and marginal cost-based prices. Some of the difficulties of this approach are highlighted, and additional, often more pressing, pricing objectives are noted, including the imperative of prices which will allow financial viability and prices which will achieve greater equity. Actual practice in developing countries is then examined with regard to tariff levels and structures. Tariff levels are compared with long run marginal costs, generally being much lower in developing countries. The tariff structures discussed include inclining block, single flat rate, two-part, unmetered and time-of-use tariffs. The question of subsidies is raised as well as the problems of implementing equitable life-line tariffs.
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    Studies on growth and filtration of the antagonistic biocontrol yeast Cryptococcus albidus
    (2005) Pickering, Mark; Harrison, STL
    A high filtration resistance has been found to hinder the dewatering of the antagonistic biocontrol yeast Crytococcus albidus. Throught literature a hypothesis was developed that the extracellular polysaccharide produced by C. albidus is the major cause of hindrance to the filtration process. Microscopic analysis of C. albidus cultures illustrated cell-bound extracellular capsule. Viscosity measurements and visual observations of precipitation of the polysaccharide with ethanol were evidence extracellular polysaccharide suspended in the surrounding media. In this study, alteration of the composition of the growth medium and various pre-filtration treatments of the yeast harvest were investigated to improve filterability. The treatments included washing the yeast to remove suspended macromolecules, exposing the yeast suspension to a high shear environment to reduce the quantity of cell-bound polysaccharide, and varying suspension temperature. Us of Saccharomyces cerevisiae (Baker's yeast) and diatomaceous earth (DAE) as filter aids were investigated as a means of further improving filterability.
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    The distribution of power: Recomendations of electrification policy
    (1996) Davis, Mark; Pickering, Mark; Steyn, Grove
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    Towards an independent system operator for South Africa
    (2010) Pickering, Mark
    Purpose of the report: This report considers the implementation of an independent system operator (ISO) in South Africa. In particular the report examines the key functions that an ISO would need to perform in the light of major policy choices facing the country. Methodology: This research was undertaken at a stage when the South African government had only made very brief policy statements about its intention to establish an ISO. No detailed discussion documents, government policy or draft legislation were available to the public. The research was therefore based on interviews with informed individuals, a review of various confidential draft policy documents and a limited review of the international literature. Terminology: Government initially used the term ‘independent system operator’. Strictly speaking this is probably not the correct term given the range of functions under consideration. Government subsequently shifted to ‘independent system and market operator’. If government plans to include transmission functions within the new entity it may be more appropriate to rather refer to ‘transmission system operator’, ‘national grid company’ or some variation of these. For the sake of consistency and clarity, ISO is throughout the report, focusing on the underlying functions to be performed.