Combined cycle

Prinsloo, G.J., Dobson, R.T., Mammoli, A.A. 2016. Model based design of a novel Stirling solar micro-cogeneration system with performance and fuel transition analysis for rural African village locations. Solar Energy 133, p 315-330 doi:10.1016/j.solener.2016.04.014

This paper describes the performance of a hybrid renewable energy system (HRES) integrated with a combined heat and power cogenerative smart microgrid as remote area power supply (RAPS) in deregulated district energy systems. The research focus on 100% renewables follows on from the ideas of the international energy society (ISES) 100% renewable energy drive, the IEEE smart villages initiative, international renewable energy alliance (IREA), the smart electric power alliance (SEPA) and the alliance for rural electrification (ARE). The proposed hybrid biogas based sun tracker concentrated solar hybrid renewable domestic hot water and power generation system. This alternative energy system design is suitable for space heating, household lighting and cooling refrigeration loads in smart villages, eco-estates, game-farms and remote islands. The study highlights the benefits of embedded generation in integrated and interactive smartgrid configurations for decentralised and district energy systems. International development initiatives such as the Alliance for Rural Electrification and the IEEE Smart Village program have been calling on engineers from developing countries to assist in reducing energy poverty through the design and development of custom designed small-scale sustainable renewable energy solutions. This paper describes the thermodynamic and electrical modeling, simulation and synthesis of a novel kit-based concentrating solar power combined heat and power or hybrid solar cogeneration system. It describes the decentralized solar co-generation system based on a combined cycle Stirling micro-CHP system that includes a low maintenance linear free piston Stirling engine with waste heat recovery, ideal for small business, residential or domestic solar home systems. The concentrating solar combined cycle power and energy system has been designed as a cost-effective community shared solar micro-combined heat and power unit to help enable solar energy utilization within the physical and socio-economic reality of isolated rural areas. This modular plug-and-play unit intends to serve as a stand-alone 100% renewable energy solar powerpack in rural microgrid energy distribution network applications where it will deliver around 3 kW of heat and 1 kW of electricity in distributed generation configurations. The focus of this paper is on the model based design approach in which the main components of the proposed solar micro-combined heat and power system have been systematically modeled on the TRNSYS and Matlab Simulink simulation platforms. This discrete digital modeling approach follows the design guide of the National Renewable Energy Laboratory Village Power Program wherein computer models are used to predict system performance. The TRNSYS model application is extended to meet compulsory World Bank and Development Agency funding and humanitarian investment requirements in terms of providing energy reform and fuel transition projections as part of proving the suitability of newly proposed solar technologies for remote area power applications. The proposed computer model applies statistical weather data to explore the performance, feasibility and fuel transition effects for the solar micro-combined heat and power system in terms of electricity and hot-water generation as well as fuel wood replacement at various locations in Southern Africa. The results show the annual power and hot water generation capability of the system for various sites across Southern Africa, and demonstrates a significant potential in reducing fuel wood usage for villages in these areas. This technology and analysis principles would also be valuable in environmental CO2 sequestration analysis, energy sustainability studies, techno-economic analysis as well as cost benefit studies for greenhouse gas (GHG) mitigation and adaptation technologies. Africa is a developing countries situated in one of the most vulnerable continents to climate variability. Climate change threatens food security and water stress from droughts and floods as well as potential extinction of plant and animal species, calling for nature conservation to reverse wood-land degradation, deforestation and erosion.
This universal distributed generation Stirling engine generation system is ideal for decentralized pre-paid energy co-operatives and pay-as-you-go solar home business models towards empowering remote off-grid villages and indigenous communal living in village communities through indigenous local sustainable energy sources. Energy production from thermodynamic micro-CHP system forms the core of a smart energy system infrastructure that makes up the rural energy system able to serve rural village communities-sustainably. It is intended to ensure sustainable rural development by providing sustainable energy that could displace traditional fossil fuels. The system uses indigenous energy resources, and with added photovoltaic PV or wind energy generation to ensure fossil fuel displacement in replacing fuels such as kerosene, paraffin, candles and wood fuel that cause human health issues and illness due to smoke inhalation. Such hybrid biofuel or biogas solar system provide a sustainable green energy solution and household home heating or district heating solution based on zero-net-energy 100% renewables. It is offered as a humanitarian aid technology to help service coalitions in support of entrepreneurial ventures into engineering for change in remote isolated off-grid rural communities at the bottom of the pyramid.
Follow on work describes the cyber-physical system aspects with smartgrid energy management and control modeling for coordination and optimization of the overall village power system. The integrated community solar and community microgrid solutions are novel in the context of thermo-electrical cogeneration, virtual power plants and hierarchical control structures for remote rural islanded village applications. Hybrid photovoltaic PV, eolica wind, small hydro and biogas cogeneration (poly-generation, tri-generation or hybrid-generation) in multi-carrier pico-grid, nano-grid or micro-grid dispatch can be used for power n energy delivery to drive appliances such as direct current DC LED lighting, fridges, radio, satellite TV, entertainment systems, and sanitation in islanded network configurations. This includes a flexible smart energy management in smart-grid architecture, data analytics and smart-meter instrumentation that includes machine-learning and artificial intelligence with mathematical and economic optimization in demand management, automated demand response, demand management and flexible controllable load curtailment. The intelligent energy management system aspects include customer engagement in control automation, intelligent self-learning, predictive optimization, energy profile or load forecasting, solar forecasting and battery energy storage integration in managing energy reserves. With smart-meter dashboard analytics, this will ensure renewable energy integration in dispersed generation with energy storage (battery, fuel-cell, tank) to ensure practical energy management that deals with the uncertainty, variability, flexibility and energy security in small-scale heat and power microgrids.
Highlights include customer engagement and cooperation in community solar energy utilization in physical & socio-economic reality of isolated rural areas; Localized rural electric power solution to ensure self-sufficient prosumer based energy in community smartgrids; Digital numerical modeling of custom designed kit-based concentrated solar tracker Stirling CSP micro-CHP system; Simulation prediction of CSP system performance in isolated rural African contexts to improve resource coordination and energy preservation; Analysis on fuel transition projections & rural energy generation reform; Need for hot water geyser type energy storage and dispatch; Demonstration of the personalized approach to power supply within sociological relevance and sustainability merit of customized community solar technology.
http://www.sciencedirect.com/science/article/pii/S0038092X16300378
https://www.researchgate.net/publication/301659032_Model_based_design_of_a_novel_Stirling_solar_micro-cogeneration_system_with_performance_and_fuel_transition_analysis_for_rural_African_village_locations