11 research outputs found
a multi parametric criteria for tidal energy converters siting in marine and fluvial environments
Abstract Marine renewable energy deployment involves site resource assessment as strategic support for installation and optimization. This part of the design needs to be based on best available measurement technologies and deployment methods, minimizing the investments. The siting and design of a kinetic energy converter (like a Tidal Energy Converter ones) require characterization of the variability of the flow velocity acting on the energy capture area in space and time, in order to assess the hydrodynamic forces, to design the structural loading and power capacity of the TEC, helping investment decisions and project financing. In this work, a site assessment procedures for emplacement of TEC machines are shown, comparing sites with different hydrogeological characteristics using the same design approach. In order to define the best conditions for siting, three case studies have been carried out, two for sea and last for river installation. The strait of Messina (Italy), a marine channel with an amphidromic point for the tides, has its minimum depth at 72 m, between Ganzirri and Punta Pezzo, deepening to 1000 m to the North East and down to 2000 m to the South. The Cook Inlet (Alaska), a large subarctic estuary in South-central Alaska which extends about 250 km from Anchorage bay to the Pacific Ocean. Tidally dominated currents control the hydrographic regime, meanwhile water levels and currents are influenced by tides coming from the Gulf of Alaska, which are significantly amplified as approaching Anchorage bay. The Pearl River Estuary and its adjacent coastal waters (China) have a length of about 70 km, a width of about 15 km and an average depth of about 4.8 m, but it has a depth of more than 20 m in its eastern part
An Externally Fired Micro Combined-Cycle, with Largely Adjustable Steam Turbine, in a CHP System
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procedure selecting pumps running as turbines in micro hydro plants
Abstract The authors present a combined method using statistical and numerical models for selecting a pump running as turbine in micro hydro plants. The data of the site (head and capacity) allow calculating two coefficients, C Q and C H , which identify the pump to use successfully as turbine in that place. A one dimensional model, starting from data available on the pumps manufacturers catalogues, reconstructs a virtual geometry of the PAT, then calculates the performances curves, head vs. capacity, efficiency vs. capacity. The procedure has been applied with the aim to select a PAT recovering energy from a pipeline whose characteristic curve is known
siting assessment for kinetic energy turbines an emplacement study for sea and river applications
Abstract The siting and design of a Tidal Energy Converter (TEC) require the characterization of the flow velocity field acting in terms of space and time, in order to assess the hydrodynamic forces, to calculate the structural loading and power capacity, also helping investment strategy and project financing. In this framework, the selection of the emplacement site is of paramount importance for optimizing efficiency of TEC. In this study, we propose site assessment procedures for emplacement of TEC machines, comparing a sea tidal site with two rivers ones. Sites differ each other from geomorphological characteristics. The Cook Inlet (South-Central Alaska) is a large subarctic estuary, which extends about 250 km from Anchorage bay to the Pacific Ocean. Tidally dominated currents control the hydrographic regime, with water levels and currents periodically influenced by tides from the Gulf of Alaska, which are significantly amplified as approaching Anchorage bay. The Chang JiÄng river (also named Yangtze, China) is the longest in Asia and the third in the world, with a huge flow rate. The Pearl River Estuary (China) has a length of about 70 km, a width of about 15 km and an average depth of about 4.8 m. It is deeper than 20 m in its eastern part, and discharges into a microtidal environment along the northern shelf of the South China Sea. The TEC performances have been compared in the three different geomorphological environments. Results show how TEC in rivers can perform up to 5.47 kW/m2, a huge value compared to the wide sea turbines, able to perform up to 10.76 kW/m2
Siting assessment for Kinetic Energy Turbines: an emplacement study for sea and river applications
Abstract The siting and design of a Tidal Energy Converter (TEC) require the characterization of the flow velocity field acting in terms of space and time, in order to assess the hydrodynamic forces, to calculate the structural loading and power capacity, also helping investment strategy and project financing. In this framework, the selection of the emplacement site is of paramount importance for optimizing efficiency of TEC. In this study, we propose site assessment procedures for emplacement of TEC machines, comparing a sea tidal site with two rivers ones. Sites differ each other from geomorphological characteristics. The Cook Inlet (South-Central Alaska) is a large subarctic estuary, which extends about 250 km from Anchorage bay to the Pacific Ocean. Tidally dominated currents control the hydrographic regime, with water levels and currents periodically influenced by tides from the Gulf of Alaska, which are significantly amplified as approaching Anchorage bay. The Chang JiÄng river (also named Yangtze, China) is the longest in Asia and the third in the world, with a huge flow rate. The Pearl River Estuary (China) has a length of about 70 km, a width of about 15 km and an average depth of about 4.8 m. It is deeper than 20 m in its eastern part, and discharges into a microtidal environment along the northern shelf of the South China Sea. The TEC performances have been compared in the three different geomorphological environments. Results show how TEC in rivers can perform up to 5.47 kW/m2, a huge value compared to the wide sea turbines, able to perform up to 10.76 kW/m2
A multi-parametric criteria for Tidal Energy Converters siting in marine and fluvial environments
Abstract Marine renewable energy deployment involves site resource assessment as strategic support for installation and optimization. This part of the design needs to be based on best available measurement technologies and deployment methods, minimizing the investments. The siting and design of a kinetic energy converter (like a Tidal Energy Converter ones) require characterization of the variability of the flow velocity acting on the energy capture area in space and time, in order to assess the hydrodynamic forces, to design the structural loading and power capacity of the TEC, helping investment decisions and project financing. In this work, a site assessment procedures for emplacement of TEC machines are shown, comparing sites with different hydrogeological characteristics using the same design approach. In order to define the best conditions for siting, three case studies have been carried out, two for sea and last for river installation. The strait of Messina (Italy), a marine channel with an amphidromic point for the tides, has its minimum depth at 72 m, between Ganzirri and Punta Pezzo, deepening to 1000 m to the North East and down to 2000 m to the South. The Cook Inlet (Alaska), a large subarctic estuary in South-central Alaska which extends about 250 km from Anchorage bay to the Pacific Ocean. Tidally dominated currents control the hydrographic regime, meanwhile water levels and currents are influenced by tides coming from the Gulf of Alaska, which are significantly amplified as approaching Anchorage bay. The Pearl River Estuary and its adjacent coastal waters (China) have a length of about 70 km, a width of about 15 km and an average depth of about 4.8 m, but it has a depth of more than 20 m in its eastern part
Tides and tidal currentsâguidelines for site and energy resource assessment
The main aim of this paper was to classify and to analyze the expeditious resource assessment procedure to help energy planners and system designers dealing with tides and tidal currents. Depending on the geographical features of the site to be evaluated, this paper reported the easiest methods to adopt for later working plans, crucial for preliminary considerations but to be supported by in situ measurements and by a more complex and detailed modelling. While tide trends are pre-dictable by using Laplace equations and Fourier series, tidal currents velocities prediction is not easy, requiring suitable methods or hydraulic applications. Natural and artificial sites were ana-lyzed and the best method for each type of them was presented. The latter together highlighting the minimum set of required information was discussed and provided as a toolkit for assessing tides and tidal current energy potential
Development and validation of a comprehensive methodology for predicting PAT performance curves
This paper presents a physics-based approach aimed to predict the performance curves of PATs (pumps as turbines). The methodology includes a tuning procedure, which allows the calibration of the physics-based model on a given dataset of pumps/PATs, and a prediction procedure, which allows the estimation of PAT performance curves for previously unknown PATs. The methodology is applied to six pumps/PATs, of which the performance curves were experimentally determined at different rotational speeds. A cross-validation process is applied in such manner that one of the six pumps/PATs is not employed for the tuning procedure and is used for validating the reliability of the prediction procedure.
The results show that, in the range ±20% with respect to the experimental BEP, the deviation of the predicted PAT performance curves from experimental curves can be acceptable from an engineering point of view, with an average value of 13.4%, 14.0% and 12.4%, for head, power and efficiency, respectively