Browsing by Author "Howells, M"

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    Electricity supply industry modeling for multiple objectives under demand growth uncertainty
    (Elsevier, 2007) Heinrich, G; Basson, L; Howells, M; Petrie, J
    Appropriate energy–environment–economic (E3) modelling provides key information for policy makers in the electricity supply industry (ESI) faced with navigating a sustainable development path. Key challenges include engaging with stakeholder values and preferences, and exploring trade-offs between competing objectives in the face of underlying uncertainty. As a case study we represent the South African ESI using a partial equilibrium E3 modelling approach, and extend the approach to include multiple objectives under selected future uncertainties. This extension is achieved by assigning cost penalties to non-cost attributes to force the model's least-cost objective function to better satisfy non-cost criteria. This paper incorporates aspects of flexibility to demand growth uncertainty into each future expansion alternative by introducing stochastic programming with recourse into the model. Technology lead times are taken into account by the inclusion of a decision node along the time horizon where aspects of real options theory are considered within the planning process. Hedging in the recourse programming is automatically translated from being purely financial, to include the other attributes that the cost penalties represent. From a retrospective analysis of the cost penalties, the correct market signals, can be derived to meet policy goal, with due regard to demand uncertainty.
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    The energy profile of a rural community
    (Energy Research Centre, 2004) Lloyd, PJ; Dick, A; Howells, M
    We present the results of a survey on domestic energy use in the community of Nkweletshini in south-western Kwa-Zulu Natal during 2002. The community has a low housing density, below the 50 households per km2 measure used by Eskom as the limit for future electrification. Houses were modest, with a median number of 3 rooms, and built of either clay or cement blocks, and generally thatched although some had corrugated iron roofs. Many in the community are employed, but it is relatively low-level employment, with a median income of about R660/month/household. 96% of all households cook on wood collected free of charge in the vicinity. 3% cook on paraffin and 1% on LP gas. The primary appliance is a wood stove; 4% of the households use an open brazier (“imbaula”). 78% of households reported problems with the fuel they used because it made them cough (43%); it smelled (30%); or it smoked and hurt the eyes (24%). 65% of the households reported a second choice of fuel, which was generally paraffin. The cost of paraffin relative to wood was cited as its major disadvantage. Cleaner fuels were preferred on social occasions, when the household had guests. Cooking took place once or twice a day, rarely in the evening, food cooked earlier in the day being heated for an evening meal. The profiles for space heating and water heating were very similar to that for cooking, with a significant quantity of wood being burned for these purposes even in summer. Space heating took place throughout the day, with a morning peak between 06h00 and 08h00, starting somewhat earlier in winter. There was little water heating during the day. There were two sources of lighting in the community, candles (70%) and paraffin lamps (30%). 59% of the candle users did not like the source of light, while 62% of the paraffin users did not like lamps. The average household bought 3 packets (each containing 6 candles) per month. The primary appliances in Nkweletshini were radios (91%, battery powered); kettles (86% of households, non-electrical); television (34%, battery powered), and cell phones (17%, battery powered). Average radio use was close to 24 h/day. The average household consumed 12.1bundles of wood per month, or somewhere between 300 and 400 kg of wood. Most households collected wood themselves – only two relied on neighbours or relatives. Wood collection was clearly a major effort. Most wood was collected first thing in the morning, somewhat earlier in summer than in winter, but even in winter 25% of the households were collecting wood between 04h00 and 06h00. It was only between the hours of midnight and 04h00 that collection ceased. 94% of the householders purchased paraffin. Monthly volumes averaged 12.6 litres per household that bought paraffin. The calculated average price was R3.00 per litre, which is very close to the known cost of paraffin in the area. Over 20% of households made use of car batteries, primarily for television, and recharged them twice a month on average. 67% of the households purchased the 9V PM9 batteries, primarily for radio, using 2 per month on average. Less than 10% of the households made much use of torches, buying about 4 batteries per month. These results are discussed in terms of the total energy demand of the households (4 000 to 5 500 MJ/month) and the time-of-day requirements that peak in the early morning rather than in the evening as is the case in urban and semi-urban environments. The potential impact of the electricity basic services support tariff on indoor air pollution and health in South Africa
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    Ranking power expansion alternatives for multiple objectives under certainty
    (Elsevier, 2007) Heinrich, G; Basson, L; Cohen, B; Petrie, J; Howells, M
    Strategic planning in the electricity supply industry is a complex task due to the multiple and often conflicting objectives of the decision makers, as well as the inherent technical and valuation uncertainties involved. As such, a transparent decision support framework is needed, for guiding information management throughout the decision process, in a way which shapes decision outcomes, and enables confident choices to be made. This paper outlines a methodology for the ranking of power expansion alternatives given multiple objectives and uncertainty, and demonstrates this using the South African electricity supply industry. This methodology uses a value function MCDA approach that is augmented with scenario analysis to yield information relating to both the relative performance and credibility of power expansion alternatives. A portfolio of preferred alternatives is then identified based on performance and confidence criteria. Finally a more detailed analysis of the reduced solution set examines short-term technology investment details alongside attribute performance information, so as to gain insight into the decision problem and relate it back to real life actions.
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    A study of demand side potential in South African industries
    (Cape Peninsula University of Technology, 2016-02-23) Hughes, A; Howells, M; Trikam, A; Kenny, A; van ES, D
    This paper looks at the potential for demand side management (DSM) in nine industries in South Africa. The DSM potential of the industries was assessed through audits and by examining the load profiles of the industries. The DSM options considered were either an improvement in energy efficiency or the shifting of electricity use to outside of the Eskom peak. DSM options that would negatively affect production were not considered. The paper introduces the study, explains why certain industries were selected as case studies and briefly summarises the findings at each site.
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    Sustainable development policies and measures: Institutional issues and electrical efficiency in South Africa Climate Policy
    (Taylor & Francis, 2007) Winkler, H; Howells, M; Baumert, K
    An innovative approach is introduced for helping developing countries to make their development more sustainable, and also to reduce greenhouse gas (GHG) emissions as a co-benefit. Such an approach is proposed as part of the multilateral framework on climate change. The concept of sustainable development policies and measures (SD-PAMs) is outlined, making clear that it is distinct from many other approaches in starting from development rather than explicit climate targets. The potential of SD-PAMs is illustrated with a case-study of energy efficiency in South Africa, drawing on energy modelling for the use of electricity in industry. The results show multiple benefits both for local sustainable development and for mitigating global climate change. The benefits of industrial energy efficiency in South Africa include significant reductions in local air pollutants; improved environmental health; creation of additional jobs; reduced electricity demand; and delays in new investments in electricity generation. The co-benefit of reducing GHG emissions could result in a reduction of as much as 5% of SA’s total projected energy CO2 emissions by 2020. Institutional support and policy guidance is needed at both the international and national level to realize the potential of SD-PAMs. This analysis demonstrates that if countries begin to act early to move towards greater sustainability, they will also start to bend the curve of their emissions path.