Browsing by Author "Merven, Bruno"
Now showing 1 - 16 of 16
Results Per Page
Sort Options
- ItemOpen AccessCosting a 2020 target of 15% renewable electricity for South Africa - Final Draft(Energy Research Centre, University of Cape Town., 2008) Marquard, Andrew; Merven, Bruno; Tyler, Emily; Hagemann, KilianThis study explores the implications of a renewable energy target, with South Africa setting and achieving 15% of electricity generated from renewables by 2020 We report the effects of 15% renewable electricity on the total cost of electricity production, investment in electricity infrastructure, and national greenhouse gas emissions. Achieving such a target will pose institutional, financing and policy challenges and we consider several options. The two most promising technologies for South African conditions are wind and solar thermal electricity.
- ItemOpen AccessEconomic and sustainable development of the power sector of Mozambique(2014) Roque, Paxis Marques Joao; Merven, BrunoMozambique has a vast potential of energy resources which are little exploited, particularly in the power sector. Mozambique’s diverse energy resource includes hydropower, natural gas, coal, biomass, solar and wind. Despite this, the country still faces constraints in increasing the level of access to energy. Therefore, the sustainable use of energy resources and the expansion and provision of reliable energy services for all districts is central to addressing many issues related with the development of the country. According to the Mozambican power utility, “Electricidade de Moçambique” (EDM), practically 97 of Mozambique’s electricity is generated from hydropower, with total installed capacity of 2179 Megawatts but due the existence of large reserves of coal and gas, the country is also intending to generate 1100 Megawatt from coal, 1790 Megawatt from gas and to increase the generation from hydro. However, before choosing those options regarding energy resources usage, it is important to assess the sustainability of the options from both socio-economic and environmental perspectives. Policies must wisely track reliable and affordable modern energy supplies and reduce the negative environmental impacts related to energy production and use and capital investments in equipment and energy infrastructure are crucial for developing the energy system. This study aims to examine socio-economic and environmental aspects of energy resource usage in Mozambique and the evaluation of Mozambique’s power supply alternatives into the future.
- ItemOpen AccessEnergy emissions: a modelling input into the Long Term Mitigation Scenarios process(Energy Research Centre, University of Cape Town., 2007) Hughes, Alison; Haw, Mary; Winkler, Harald; Marquard, Andrew; Merven, BrunoEmissions from energy supply and use constitute by far the largest part of South Africa’s total greenhouse gas (GHG) emissions. Hence energy modeling is a key analytical basis for the information provided to the long-term mitigation scenarios (LTMS) process. This report contains the technical information provided by the energy modeling team at the Energy Rserach Centre, led by Alison Hughes, to the Scenario Building Team which developed the LTMS scenarios. The information was integrated into the overall Technical Report (with appendices), its Technical Summary and the Scenario Document.
- ItemMetadata onlyEnergy Modeling: A modelling input into the Long Term Mitigation Scenarios process(2007) Hughes, Alison; Haw, Mary; Winkler, Harald; Marquard, Andrew; Merven, BrunoEmissions from energy supply and use constitute by far the largest part of South Africa’s total greenhouse gas (GHG) emissions. Hence energy modeling is a key analytical basis for the information provided to the long-term mitigation scenarios (LTMS) process. This report contains the technical information provided by the energy modeling team at the Energy Rserach Centre, led by Alison Hughes, to the Scenario Building Team which developed the LTMS scenarios. The information was integrated into the overall Technical Report (with appendices), its Technical Summary and the Scenario Document.
- ItemOpen AccessInvestigating the current and future role of paraffin in South Africa(Energy Research Centre, University of Cape Town., 2013) Tait, Louise; Merven, Bruno; Senatla, MamahlokoThis research investigates what the future of paraffin could and should be in South Africa, in particular whether this could be envisioned as transforming paraffin into a safe fuel for households. Alternatively, might South Africa look to assist households with a transition towards other modern fuels.
- ItemOpen AccessIs nuclear power a cost optimal solution for Kenya's electricity generation mix?(2016) Odera, Sarah; Stone, Adrian; Merven, BrunoIn 2010, the adoption of nuclear power was declared a national priority in Kenya. Thereafter, a target of obtaining 4000 MW of nuclear power by the year 2030 was documented in Kenya's Least Cost Power Development Plan (LCPDP) 2010-2031. The nuclear target has drawn a lot of opposition from some Kenyans whose concerns are centered on the cost and safety risks incurred by nuclear power. The government however states that nuclear power is necessary for the diversification of the electricity generation mix and satisfaction of future electricity demand. The aim of this thesis was therefore to determine whether electricity demand in Kenya could be met without nuclear power and whether it was more economical to utilize nuclear power in Kenya's electricity generation mix rather than increase the generation capacity of other sources of electricity available to Kenya. To answer these questions, two capacity expansion models were developed. These models like the LCPDP studied the period between 2010 and 2031. The aim of the first model was to replicate LCPDP, and in doing so verify the necessity of nuclear power for meeting Kenya's future electricity demand. As far as was possible, the validation model utilized the same assumptions, including the same demand forecast that was used to develop the LCPDP 2010-2031. The validation was done to verify the necessity of nuclear power from the LCPDP's set of assumptions. The second model was developed with the aim of obtaining an updated capacity expansion plan. This plan utilized recent assumptions including an updated demand forecast. The demand was forecasted using regression of historical electricity demand against GDP in the commercial and industrial category. In the domestic category historical demand was regressed against GDP per capita and population. Based on recent data and economic forecasts, a GDP growth rate of 6% was used to forecast the electricity demand instead of 9% used in the LCPDP's demand forecast. [Please note: this thesis file has been deferred until June 2018]
- ItemOpen AccessModelling the potential impact of net metering in South Africa(2013) McCall, Bryce; Hughes, Alison; Merven, BrunoThis work has two main objectives, first to create a working energy model of South Africa’s electricity sector using the open source software; OSeMOSYS, and secondly, using this model to understand the unstudied effects of net metered capacity within the country and how this affects the planning of the energy sector in the future, which is done through processes such as the Integrated Resource Plan (IRP). Using a combination of electricity tariffs and solar PV price projections, and the Bass diffusion model, an estimated range of the total amount of installed MW capacity of rooftop solar PV within the residential sector of South Africa was determined.
- ItemOpen AccessPerson tracking in 3D using Kalman filtering in single and multiple camera environments(2004) Merven, BrunoWe present a multi-camera person tracker solution that makes use of Kalman filtering principles. The tracking system could be used in conjunction with behaviour analysis systems to perform automated monitoring of human activity in a range of different environments. Targets are tracked in a 3-D world-view coordinate system which is common to all cameras monitoring the scene. Targets are modelled as ellipsoids and their colour information is parameterised by RGB-height histograms. Observations used to update the target models are generated by matching the targets in the different views. 3-D tracking requires that cameras are calibrated to the world coordinate system. We investigate some practical methods of obtaining this calibration information without laying out and measuring calibration markers. Both tracking and calibration methods were tested extensively using 6 different single and multiple camera test sequences. The system is able to initiate, maintain and terminate the tracks of several people in cluttered scenes. However, further optimisation of the algorithm is required to achieve tracking in real time.
- ItemOpen AccessPolicy options for the sustainable development of the power sector in Zambia(2012) Tembo, Bernard; Hughes, Alison; Merven, BrunoMany climate change studies project that occurrence of droughts (due to dry years) in Southern Africa will increase; this raises concerns over Zambia's electricity system. Currently, over 99% of Zambia's electricity is supplied by hydropower, which is vulnerable to droughts. With Zambia targeting to be a middle income industrialised country by 2030, it isimportant that the impacts of droughts on the electricity system are understood, and how the system's adaptive capacity can be improved. This is imperative if the system were to enhance economic development. The main focus of this research therefore, was to develop an understanding of how Zambia's electricity system would evolve in different economic and climatic scenarios. A comprehensive electricity model for Zambia was developed after reviewing literature on Zambia's electricity sector and energy planning in a developing country context. A Scenario planning approach was used to model and analyse the electricity system that would be required to meet demand in two climatic scenarios (average and dry year river-flows) and for different economic growth scenarios. The results showed that the supply system has to be increased in order to support economic development. In a dry year scenario, the availability of the hydro technologies reduces significantly and this leads to a considerable increase in the average generation cost of the system. The introduction of renewable energy and coal technologies into the system lessens the impacts of droughts. Carbon emitting technologies such as coal and oil are still viable supply options even with a carbon price of $50 per tonne. Only low and base-case growth scenarios need an explicit diversification policy since least cost policy in the high growth scenario (the middle income growth trajectory) leads to a diverse supply system. Implementing a diversification policy in the high growth scenario increases average generating cost without improving the system's adaptive capacity. The most cost effective way of increasing the system's adaptive capacity is by importing electricity and gradually increasing share of renewable and coal technologies in the system. Further research on how electricity trade in Southern Africa could be enhanced, should be done.
- ItemOpen AccessQuantifying the energy needs of the transport sector for South Africa: a bottom-up model(Energy Research Centre, University of Cape Town., 2012) Merven, Bruno; Stone, Adrian; Hughes, Alison; Cohen, BrettTransport is a large consumer of energy in South Africa and vital for economic development. Currently the transport sector consumes 28% of final energy, the bulk of which, 97%, is in the form of liquid fuels. As the population grows and becomes wealthier, so the demand for passenger transport and private vehicles increases; similarly, rising GDP drives the demand for freight transport. Supply interruptions are costly to the economy and careful long‐term planning is required to ensure that there is sufficient infrastructure to support the efficient functioning and growth of the transport sector in the future.
- ItemOpen AccessReal options valuation of a power generation project : a Monte Carlo approach(2008) Merven, Bruno; Becker, RonaldIn today's economic environment characterised by change, uncertainty, and the need for flexibility, it is becoming important for decision makers to account for both uncertainty and the companys ability to react to new information. Real options has emerged as an approach that addresses this challenge by drawing parallels between the real economy and the use and valuation of financial options. Monte Carlo simulation is a powerful technique for option valuation, but because of its forward looking nature is normally applied when early exercise is not allowed. In the real economy, this would be limiting because flexibilities that exist are not normally constrained to particular exercise dates. The Least-Squares Monte Carlo (LSM) is an approach that allows for the valuation of options where early exercise is possible. In this thesis, we present an implementation of the LSM approach to the Real Options valuation of a project that involves the investment in a new open cycle (OCGT) gas power generation plant, used to supply peak electricity demand in an open electricity wholesale market. The embedded flexibilities that are considered are the option to expand, and the option to abandon the project. The uncertainties that the project is exposed to include: the cost of fuel, the price at which electricity is sold and the quantity of electricity sold each year. We show that the LSM approach offers several benefits for the valuation of such projects with complex payoff functions.
- ItemOpen AccessReliability evaluation of solar power in South Africa's power system(2014) Bailey, Nicolas; Stone, Adrian; Merven, BrunoGlobal utilisation of renewable energy sources such as solar photovoltaics (PV) in electric power systems is growing rapidly due to government incentives, and negative environmental impacts associated with conventional generators. Many consider solar PV as a promising alternative source of energy due to its apparent environmental, social and economic benefits. This together with government incentives and programmes such as the renewable energy independent power procurement program (REIPPPP) has allowed for investment in PV in South Africa (SA). Solar irradiation is a variable energy source and thus serious consideration needs to be given to the effect that PV might have on the reliability of the system. As a result traditional methods of evaluating power system reliability cannot be used when utility-scale PV is introduced to the system. Thus probabilistic methods are commonly employed to evaluate reliability. In this thesis time series data was used to simulate the yield from 27 PV plants, as defined by round 1 and round 2 of the REIPPP process, through a yield model developed for this investigation.
- ItemOpen AccessReliability investigation of the South African power generation system with the inclusion of wind energy(2014) Maseela, Tiisetso; Merven, BrunoRenewable energy sources such as wind energy for electric power supply are receiving serious consideration around the world due to global environmental concerns associated with conventional generation and depleted conventional energy resources to meet increasing electricity demand. This is more than evident in South Africa, where the recently launched Renewable Energy Independent Procurement Program (REIPPPP) has a proposed capacity of 3725MW, allocating 1850MW to wind energy. This dissertation investigates the effects that geographical dispersion and penetration level have on the wind capacity credit and the reliability of the South African power generation system, by estimating the capacity credit. Some of the estimates are tested using a simplified dispatch model, which is also used to estimate other indicators such as the expected energy not served and CO2 emissions of the system for different wind configurations. The sensitivity of the capacity credit definition is further investigated through two definitions. Several scenarios are used to investigate the capacity credit of wind generation, based on the updated IRP base case scenario.
- ItemOpen AccessSocio-economic implications of mitigation in the power sector including carbon taxes in South Africa(Energy Research Centre, University of Cape Town., 2014) Merven, Bruno; Moyo, Alfred; Stone, Adrian; Dane, Anthony; Winkler, HaraldThe structure of this paper is as follows. The first section provides a discussion of recent developments within South Africa aimed at increasing the contribution of renewable energy. The second section gives a brief description of the carbon tax that National Treasury plans to implement and also provides an overview of previous studies on the implications of a carbon tax in South Africa. The linked model that we use for our analysis is described in section 3. This is then followed in section 4 by a description of the scenarios that we modelled, with results presented in section 5. The last section presents the conclusions and recommendations for further research.
- ItemOpen AccessTechno-economic modelling of cogeneration options for the South African sugar industry(2022) Masenda, Joseph; Merven, BrunoCogeneration is a core part of the SA sugar industry operations. Most factories in SA already cogenerate, but not to their full potential. Improving cogeneration through better energy utilisation than the usual status-quo can potentially enhance profitability. However, investment in cogeneration in the sugar industry is not taking place and although factories have proven to be able to produce excess power, many are not selling it back to the national grid. This research aimed to further the understanding of the SA sugar industry cogeneration options with the use of techno-economic modelling methods over a planning horizon extending to 2040. The methodological approach adopted for the study, configures the industry's cogenerating system, and allowed the adoption of additional options likely to play a role in assisting cogenerating performance in 2025. Some cogenerating technologies that were explored were back-pressure and condensing extraction steam turbines, as well as, high-efficiency gas engines in open and closed cycles. The least-cost optimizing TIMES modelling framework was used to evaluate the cogeneration investment decision for different cogeneration configurations under different scenarios, and to capture some of the uncertainties faced by the industry. Each scenario was evaluated using a set of techno-economic indicators, justifying the viability of technological implementations in cogenerating system pathways. Focusing on these transformative pathways highlighted diversification cogenerating options, whilst simultaneously ensuring the fulfilment of the industry's sugar production obligations, for the domestic as well as foreign market under pressure from competitive forces. Input data for model parameters stemmed from literature and information sources applied to Microsoft excel spreadsheets calculations. Analysed outcomes were scrutinised using tableau, which generated output data from iterating modelled power purchase agreement (PPA) and break-even tariff determinations. The assessment of generated transformative pathways was compared to metrics from other sugar-producing countries, with successfully diversified mills, using evaluated scenarios to emphasize the unit costs per energy in R2015/KWh. Research findings showed cogeneration feasibility at subsidised tariffs of between 1.20 and 1.76 R/kWh for steam turbines and gas turbines in open cycles, with combinedcycling from intergrated bagasse gasification being feasible from 1.20 to 1.37 R/KWh. Feasibly installed CHP technologies were concluded to have potential magnitudes of between 350 up to 800 MWe depending on the scenario.
- ItemOpen AccessTechno-Economic modelling of hybrid renewable mini-grids for rural electrification planning in Sub-Saharan Africa(2018) Ireland, Gregory; Merven, BrunoAccess to clean, modern energy services is a necessity for sustainable development. The UN Sustainable Development Goals and SE4ALL program commit to the provision of universal access to modern energy services by 2030. However, the latest available figures estimate that 1.1 billion people are living without access to electricity, with over 55% living in Sub-Saharan Africa. Furthermore, 85% live in rural areas, often with challenging terrain, low income and population density; or in countries with severe underinvestment in electricity infrastructure making grid extension unrealistic. Recently, improvements in technology, cost efficiency and new business models have made mini-grids which combine multiple energy technologies in hybrid systems one of the most promising alternatives for electrification off the grid. The International Energy Agency has estimated that up to 350,000 new mini-grids will be required to reach universal access goals by 2030. Given the intermittent and location-dependent nature of renewable energy sources, the evolving costs and performance characteristics of individual technologies, and the characteristics of interacting technologies, detailed system simulation and demand modelling is required to determine the cost optimal combinations of technologies for each-and-every potential mini-grid site. Adding to this are the practical details on the ground such as community electricity demand profiles and distances to the grid or fuel sources, as well asthe social and political contexts,such as unknown energy demand uptake or technology acceptance, national electricity system expansion plans and subsidies or taxes, among others. These can all have significant impacts in deciding the applicability of a mini-grid within that context. The scope of the research and modelling framework presented focuses primarily on meeting the specific energy needs in the sub-Saharan African context. Thus, in being transparent, utilizing freely available software and data as well as aiming to be reproducible, scalable and customizable; the model aims to be fully flexible, staying relevant to other unique contexts and useful in answering unknown future research questions. The techno-economic model implementation presented in this paper simulates hourly mini-grid operation using meteorological data, demand profiles, technology capabilities, and costing data to determine the optimal component sizing of hybrid mini-grids appropriate for rural electrification. The results demonstrate the location, renewable resource, technology cost and performance dependencies on system sizing. The model is applied for the investigation of 15 hypothetical mini-grids sites in different regions of South Africa to validate and demonstrate the model’s capabilities. The effect of technology hybridization and future technology cost reductions on the expected cost of energy and the optimal technology configurations are demonstrated. The modelling results also showed that the combination of hydrogen fuel cell and electrolysers was not an economical energy storage with present day technology costs and performance. Thereafter, the model was used to determine an approximate fuel cell and electrolyser cost target curve up to the year 2030. Ultimately, any research efforts through the application of the model, building on the presented framework, are intended to bridge the science-policy boundary and give credible insight for energy and electrification policies, as well as identifying high impact focus areas for ongoing further research.