Stand-alone power system

About: Stand-alone power system is a research topic. Over the lifetime, 8650 publications have been published within this topic receiving 192397 citations. The topic is also known as: Stand-alone photovoltaic power system.

Sensing-Driven Energy Purchasing in Smart Grid Cyber-Physical System

Abstract: Distributed and renewable-energy resources are likely to play an important role in the future energy landscape as consumers and enterprise energy users reduce their reliance on the main electricity grid as their source of electricity. Environmental or ambient sensing of parameters such as temperature and humidity, and amount of sunlight and wind, can be used to predict electricity demand from users and supply from renewable sources, respectively. In this paper, we describe a Smart Grid Cyber-Physical System (SG-CPS) comprising sensors that transmit real-time streams of sensed information to predictors of demand and supply of electricity and an optimization-based decision maker that uses these predictions together with real-time grid electricity prices and historical information to determine the quantity and timing of grid electricity purchases throughout the day and night. We investigate two forms of the optimization-based decision maker, one that uses linear programming and another that uses multi-stage stochastic programming. Our results show that sensing-driven predictions combined with the optimization-based purchasing decision maker hosted on the SG-CPS platform can cope well with uncertainties in demand, supply, and electricity prices and make grid electricity purchasing decisions that successfully keep both the occurrence of electricity shortfalls and the cost of grid electricity purchases low. We then examine the computational and memory requirements of the aforementioned prediction and optimization algorithms and find that they are within the capabilities of modern embedded system microprocessors and, hence, are amenable for deployment in typical households and communities.

The Impact of Wind Generation on Wholesale Electricity Prices in the Hydro-Rich Pacific Northwest

Abstract: Extant literature documents that wind generation can reduce wholesale electricity market prices by displacing conventional generation. But how large is the wholesale price effect of wind generation in an electricity market dominated by hydroelectric generation? We explore this question by analyzing the impact of wind generation on wholesale electricity prices in the Pacific Northwest region of the United States. This hydro-rich system tends to be energy-limited, rather than capacity-constrained, with its marginal generation during the hydro runoff season often a hydro unit, instead of a natural-gas-fired unit. We find that increased wind generation reduces wholesale market prices by a small, but statistically-significant, amount. While a hydro-rich system can integrate wind generation at a lower cost than a thermal-dominated region, the direct economic benefits to end-users from greater investment in wind power may be negligible.

Electric grid stability and the design of sustainable energy systems

Abstract: Today, in most countries, electricity is produced either on hydropower or on large steam turbines on the basis of fossil fuels or nuclear power. Electricity from distributed generation constitutes only small amounts. Until now, the task of balancing supply and demand and the task of securing frequency and voltage on the grid has been left solely to large production units. Meanwhile, the implementation of cleaner technologies, such as renewable energy, combined heat and power production and energy conservation, is necessary for future sustainable energy systems. Consequently, such distributed production units sooner or later need to contribute to the task of securing a balance between electricity production and consumer demands. This paper presents technical designs of potential future flexible energy systems, which will be able both to balance production and demand and to secure voltage and frequency requirements on the grid.