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Load shifting from peak to off-peak hours changes the electricity load profile and allows users to control the peak electricity demand and optimise the electricity cost. Power Pinch Analysis (PoPA) has been used recently to guide load shifting aimed at reducing the electricity maximum demand. This work applies the PoPA to optimise the overall electricity cost for a hybrid power system by performing cost-effective load shifting that takes advantage of the peak and off-peak electricity tariff. Two new heuristics for load shifting are proposed in this work. The results show that the total outsourced electricity during the peak hours has been successfully distributed to the off-peak hours to minimise the electricity cost. [ABSTRACT FROM AUTHOR]

Modeling tools for the optimal Hybrid Power Systems (HPS) supply planning and demand management have been relatively established. However, complementary tools that can provide planners, decizion-makers, energy managers and electrical as well as power engineers with graphical and visualization insights that are vital for better conceptual understanding of the problems, particularly at the onset of hybrid power systems planning and design, have just been developed over the last five years. This paper reviews the six-year development of the insight-based graphical and algebraic Process Integration (PI) tools for the optimal HPS supply planning and demand management, i.e., from its inception in the year 2011, until 2016. Known as the Power Pinch Analysis (PoPA), the tool has been among the next-generation PI techniques for resource conservation following the developments of the heat, mass, water, gas, materials, property, solid and carbon emission pinch analysis techniques. This paper discusses the progress, challenges and contributions of PoPA in promoting Renewable Energy (RE) utilization in HPS. Case studies on implementation of PoPA for HPS planning and design presented in the paper show encouraging improvement on HPS profitability and reliability. [ABSTRACT FROM AUTHOR]

Feed-in Tariff (FiT) has been one of the most effective policies in accelerating the development of renewable energy (RE) projects. The amount of RE electricity in the FiT purchase agreement is an important decision that has to be made by the RE project developers. They have to consider various crucial factors associated with RE system operation as well as its stochastic nature. The presented work aims to assess the sensitivity and profitability of a hybrid power system (HPS) in cases of RE system failure or shutdown. The amount of RE electricity for the FiT purchase agreement in various scenarios was determined using a novel tool called On-Grid Problem Table based on the Power Pinch Analysis (PoPA). A sensitivity table has also been introduced to assist planners to evaluate the effects of the RE system's failure on the profitability of the HPS. This table offers insights on the variance of the RE electricity. The sensitivity analysis of various possible scenarios shows that the RE projects can still provide financial benefits via the FiT, despite the losses incurred from the penalty levied. [ABSTRACT FROM AUTHOR]

The difference in electricity pricing based on the time of power use has led to load shifting from peak to off-peak hours in hybrid power systems (HPS). Apart from optimising electricity cost, shifting of the load may also change the capacity of storage in the system. Power Pinch Analysis has been recently applied to guide load shifting aiming to minimise the cost of electricity, considering the peak and off-peak electricity pricing. The HPS was assumed to be ideal with 100% efficiency, which is not achievable in actual operational condition. This work extends the study by scrutinising the effects of peak-off-peak load shifting on the capacity of storage in HPS. The effects of energy losses due to the inefficiency during power conversion, transfer and storage in the HPS are considered in developing shifting heuristics to ensure optimal storage size is achieved. Implementation of the proposed load shifting strategy on a case study demonstrates that a reduction of up to 30% in the storage size can be achieved, which led to a minimum storage cost. The distribution of peak hours' demand to off-peak hours also successfully provide significant savings in the electricity bill. [ABSTRACT FROM AUTHOR]

Development of Power Pinch Analysis (PoPA) for the design and optimisation of Hybrid Power Systems (HPS) is steadily progressing. Even though PoPA has been developed for a wide range of applications in HPS design and analysis, the economic aspect still needs more attention. Screening of various renewable energy (RE) technologies in HPS is crucial as different technologies may have different cost and efficiencies, and affect the overall system economics. This work presents a novel framework for the design of a cost-effective HPS by incorporating PoPA with a cost-screening tool known as the Systematic Hierarchical Approach for Resilient Process Screening (SHARPS). SHARPS, which was originally developed to screen various process changes options in water networks is adapted to perform economic analysis and RE technology screening in power networks. Two strategies namely substitution and intensification have been proposed, in order to customise a cost-effective HPS. The presented framework provides a handy and effective measure to visualise the trade-off between the performance and cost of various potential RE technologies for HPS. Application of the framework on a case study demonstrates that the HPS design has been successfully customised with the RE technology scheme and capacity acceptable to the owner, while meeting its targeted payback period of 10 y. [ABSTRACT FROM AUTHOR]

The hybrid power system (HPS) that integrates diesel/biodiesel plant with renewable energy (RE) technologies has become increasingly popular to alleviate greenhouse gases emissions issue of the sole diesel/biodiesel power system. Integrated diesel-RE power system offers cleaner power supply while minimising cost of diesel fuel and diesel system maintenance. The use of Power Pinch Analysis (PoPA) method for the integration of diesel plants and RE systems into HPS with the objective to minimise fuel requirement and operational time of diesel generator has been presented. This work aims to achieve the same objective via probability theory utilisation, to simplify the PoPA procedure involving the matching of various routes for power flows. The extended technique called the Probability-Power Pinch Analysis (P-PoPA) can give accurate results as those established from the PoPA method within a shorter analysis time because it replaces the tedious manual matching step with correction factors. All probable routes of power from RE and diesel generators to demands are considered in computing the correction factors, in order to target the minimum diesel power in the integrated system. The result of a Case Study demonstrates that 19% saving in diesel fuel consumption can be realised if the present diesel station is supported with renewable solar power in an HPS. The result of the P-PoPA method is accurate with a very minor deviation to that from the conventional PoPA technique. [ABSTRACT FROM AUTHOR]