Autarkic energy systems : balancing supply and demand with energy storage and controls in local energy micro-grids

摘要

When visioning for best possible future energy systems in a world with growing populations, limited fossil fuel resources, rising energy prices and less energy security - more individuals, communities and cities are looking to utilise autarkic principles to harvest, store and optimise use of local energy resources. Energy autarky can be described as a location that relies on its own energy resources for generating the useful energy required to sustain the society within that region or a situation in which a region does not import substantial amounts of energy resources. Functioning autarkic energy systems typically require a micro-grid, well understood energy demand and supply characteristics, opportunities for energy storage of various types and controls able to manage the harmonisation of system components. A critical additional ingredient is users who can work within constraints created by the adoption of autarkic principles. To elaborate the challenges and explore the issues involved with autarkic energy concepts this paper reports on the output from a workshop convened to investigate the role that energy autarky might play in delivering societies able to deliver the ambitious renewable generation targets set by both Scottish and UK Governments. In addition, monitored data from a community micro-grid system in Northern Scotland is analysed and presented to provide additional understanding of the complexities and opportunities created by an autarkic approach. The output from the workshop identified that whilst it is probable that a dogmatic interpretation of energy autarkic will not be universally applicable, the underlying principles represent a bottom up way of widening participation in the development of future energy provision models. Whilst a number of issues and barriers were raised regarding its adoption, the attendees recognised that energy autarky represented a very positive and empowering vision for translating global scale issues to local energy transition. The analysis of monitored generation and demand data from a community micro-grid underlined the problems associated with supply-demand matching with intermittent generation and the need to place an emphasis on the community or entity as an open system that is able to participate in a full range of trading opportunities. Similarities were found between the types of behaviour necessary to create load responses relevant to energy networks containing large penetrations of renewable generation and communities set up along energy autarkic principles.