A Cost–Benefit Based, Parametric Procedure to Screen Existing Irrigation and Municipal Supply Reservoirs for Wind Energy Storage

Abstract

Pumped hydro storage (PHS) is one of the more suitable energy storage technologies to provide bulk storage of intermittent renewable energy sources (RES) such as wind. Since the main limiting factors to the expansion of this mature technology are environmental and financial concerns, the use of an existing reservoir can help mitigate both types of impacts. In addition, the high number of reservoirs for municipal and irrigation supply in many areas of the world makes the idea of using PHS as a relatively diffuse, open-market, technology for RES management attractive. These arguments in favor of PHS must, however, be convincing for investors and regulators from an economic standpoint. To this end, this paper presents a methodological tool to screen the feasibility of a PHS facility around an existing reservoir based on the principles of cost-benefit analysis, calibrated with data from Sicily, Italy. Each potential plant is characterized by two locational and two plant-specific parameters. Costs and benefits are assessed through a simulation model of the storage-release process on an hourly basis. Costs include both investment, and operation and maintenance expenditures, while the benefits considered include the opportunity cost of the current energy mix substituted by the stored energy, and the avoided CO 2 emissions. The evaluation exercise is carried out parametrically, i.e., looking at a large number of combinations of the four parameters, in order to explore a wide range of possible plant configurations and to identify optimal ones under different locational conditions. A sensitivity analysis performed on models' parameters points out the sensitivity of results to benefit, rather than cost-related, input parameters, such as the efficiency of the generating and pumping system and the opportunity cost of energy.2 of 18 peak/off-peak, working mode [8][9][10][11][12]. Considering construction of a new plant therefore requires a thorough assessment of their techno-economic feasibility based on the specific supply-demand conditions at the appropriate timescale (typically one hour or less).The major drawback of PHS as storage technology lies in the long construction times and environmental concerns [13]. Although there is a growing interest in smart, sustainable solutions, envisaging small PHS plants [14] especially for small islands and isolated grids [15][16][17][18], PHS plant construction is a major technical and financial effort. The full development of a PHS project takes approximately 15 years from time of inception to commissioning. Retrofitting of existing hydropower schemes with PHS has a lower environmental impact and is often seen as a more benign solution, as the receiving environment has already been modified and is regulated by the existence of the hydropower plant. Where hydropower reservoirs do not exist or are not adequately developed, an intermediate solution can be to use the storage capacities of existing water reservoirs for water supply. In fact, many reservoirs, especially those for irrigation,...

Environmental Benefits and Economical Sustainability of Urban Wastewater Reuse for Irrigation—A Cost-Benefit Analysis of an Existing Reuse Project in Puglia, Italy

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Low Frequency Oscillations in a Hydroelectric Generating System to the Variability of Wind and Solar Power

“…The DFIG exhibits a flexible working mode due to its AC voltage excitation system which easily achieves the variable-speed constant frequency (VSCF) generation. The Park transformation can be used to represent the dynamical model of the DFIG in a synchronously rotating dq frame and in this frame, the DFIG model can be expressed as [38]: The combined block diagram representation of the wind turbine and mechanical drive shaft model is shown in Figure 9. As shown in Figure 9, the input of the wind turbine are the blade angle and wind speed, and the output is the aerodynamic torque.…”

“…Moreover, some papers are from the economic, policy and environment viewpoint. In [38][39][40][41][42], the market value and environmental benefits of the hybrid system is successfully quantified from the perspective of data statistics and the corresponding policy support is also recommended. Nevertheless, a quantitative analysis of the coordinating influences between the hydropower system and wind/solar systems is lacking.…”

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