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A New Preliminary Model to Optimize PATs Location in a Water Distribution Network

Morani, M. C., Carravetta, A., D’Ambrosio, C., & Fecarotta, O. (2020). A New Preliminary Model to Optimize PATs Location in a Water Distribution Network. In Environmental Sciences Proceedings (Vol. 2, No. 1, p. 57)

Abstract

Water distribution networks are low-energy efficiency systems, due to the high energy consumption, as well as the large amount of water leakage, which are caused by high pressures in the networks. In this study, the optimal location of pumps as turbines (PATs) within a water distribution network is investigated in order to maximize the production of energy and water savings, as well as minimize installation costs. A literature mathematical model has been employed as reference model and the weaknesses of this previous study have been overcome by new constraints. The main preliminary results of the new optimization procedure will be presented and compared with the literature results. According to the results, the new optimization ensures a good solution, in term of water and energy savings, with low investment cost and a fast return in investment.

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Optimal Regulation of Variable Speed Pumps in Sewer Systems

Cimorelli, L., & Fecarotta, O. (2020). Optimal Regulation of Variable Speed Pumps in Sewer Systems. In Environmental Sciences Proceedings (Vol. 2, No. 1, p. 58).

Abstract

In this work, the optimal regulation of variable speed pump (VSP) was solved by means of two optimization algorithms: a mixed-integer optimizer based on the BONMIN (Basic Open-Source Nonlinear Mixed Integer Programming) package, and an original hybrid genetic algorithm (GA) called GA–Powell’s direction set method (PDSM), which employs a derivative free inner optimizer, that is, the Powell’s direction set method (PDSM). The obtained results show how the use of a strategy based on the optimal regulation of VSP allows to obtain huge energy cost savings. The analysis of the results shows that the regulation of the plant does not apparently follow a general rule.

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A Performance Prediction Model for Pumps as Turbines (PATs)

Fontanella, S., Fecarotta, O., Molino, B., Cozzolino, L., & Della Morte, R. (2020). A Performance Prediction Model for Pumps as Turbines (PATs). Water, 12(4), 1175.

Abstract

In recent years, the interest towards the use of pumps operating as turbines (PATs) for the generation of electrical energy has increased, due to the low cost of implementation and maintenance. The main issue that inhibits a wider use of PATs is the lack of corresponding characteristic curves, because manufacturers usually provide only the pump-mode performance characteristics. In the PAT selection phase, the lack of turbine-mode characteristic curves forces users to expend expensive and time-consuming efforts in laboratory testing. In the technical literature, numerous methods are available for the prediction of PAT turbine-mode performance based on the pump-mode characteristics, but these models are usually calibrated making use of few devices. To overcome this limit, a performance database called Redawn is presented and the data collected are used to calibrate novel PAT performance models.

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Zero-net energy management for the monitoring and control of dynamically-partitioned smart water systems.

Giudicianni, C., Herrera, M., di Nardo, A., Carravetta, A., Ramos, H. M., & Adeyeye, K. (2020). Zero-net energy management for the monitoring and control of dynamically-partitioned smart water systems. Journal of Cleaner Production, 119745. 

Abstract

The optimal and sustainable management of water distribution systems still represent an arduous task. In many instances, especially in aging water net-works, pressure management is imperative for reducing breakages and leakages. Therefore, optimal District Metered Areas represent an effective solution to decreasing the overall energy input without performance compromise.

Within this context, this paper proposes a novel adaptive management framework for water distribution systems by reconfiguring the original network layout into (dynamic) district metered areas. It utilises a multiscale clustering algorithm to schedule district aggregation/desegregation, whilst delivering energy and supply management goals. The resulting framework was tested in a water utility network for the simultaneously production of energy during the day (by means of the installation of micro-hydropower systems) and for the reduction of water leakage during the night.

From computational viewpoint, this was found to significantly reduce the time and complexity during the clustering and the dividing phase. In addition, in this case, a recovered energy potential of 19 MWh per year and leakage reduction of up to 16% was found. The addition of pump-as-turbines was also found to reduce investment and maintenance costs, giving improved reliability to the monitoring stations. The financial analyses to define the optimal period in which to invest also showed the economic feasibility of the proposed solution, which assures, in the analysed case study, a positive annual net income in just five years.

This study demonstrates that the combined optimisation, energy recovery and creation of optimized multiple-task district stations lead to an efficient, resilient, sustainable, and low-cost management strategy for water distribution networks. 

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Estimating regional potential for micro-hydropower energy recovery in irrigation networks on a large geographical scale

Miguel Crespo Chacón, Juan Antonio Rodríguez Díaz, Jorge García Morillo, Aonghus McNabola, (2020); Estimating regional potential for micro-hydropower energy recovery in irrigation networks on a large geographical scale, Renewable Energy, Volume 155, 2020, pp 396-406.

Abstract

Micro-hydropower has been highlighted as a potential technology suitable for installation in irrigation networks to reduce system overpressures and to reduce the net energy consumption of the irrigation process. However, the full impact of this technology on a large regional scale is unknown.

Artificial Neural Networks and regression models were used in this research to predict the energy recovery potential for micro-hydropower in on-demand pressurised irrigation networks across a large spatial scale.  Predictors of energy recovery potential across spatial unit areas included: Irrigated land surface area, irrigation crop water requirements, rainfall, evapotranspiration, and mean topographical slope.  The model was used to predict the energy recovery potential across the 164,000 ha of the Spanish provinces of Seville and Cordoba in the absence of hydraulic models. 

A total of 21.05 GWh was identified as the energy potential which could have been recovered using micro-hydropower during the 2018 irrigation season. This amount of energy would have potentially reduced the energy consumption of the irrigation process in this region by approximately 12.8%. A reduction in energy consumption in the agriculture sector of this magnitude could have significant impacts on food production and climate change.

The main novelty of this paper lies in the assessment of micro hydropower resources in operating irrigation networks on a large geographical scale, in areas where no information is available. It provides an approximation of the existing potential using computational methods. 

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Pulsating spiral Poiseuille flow

Manna, M. & Vacca, A. & Verzicco, R.. (2020). Pulsating spiral Poiseuille flow. Journal of Fluid Mechanics. 890. 10.1017/jfm.2020.125. 

Abstract

Direct numerical simulation of the Navier–Stokes equations has been used to investigate the Taylor–Couette flow with an imposed pulsatile axial pressure gradient resulting in a spiral Poiseuille flow modulated by an oscillating forcing. Keeping the Reynolds and Taylor numbers constant, both the amplitude and frequency of the oscillating component are varied to span a small region of the phase space.

In the narrow-gap geometry considered in this study, the base flow (spiral Poiseuille flow) is in the turbulent regime whereas the oscillating component is laminar. It has been found that the effect of the oscillation is to induce a global flow laminarization provided the frequency is sufficiently small (at constant amplitude) or the amplitude is sufficiently large (at constant frequency).

The coupling between steady and oscillating components has been analysed with the help of long-time and phase-averaged statistics. The reverse transition mechanism has been associated to an anisotropic modification of the Reynolds stress tensor components, which has been shown to be caused by an alteration of the pressure–strain interaction.

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Transient-Flow Induced Compressed Air Energy Storage (TI-CAES) System towards New Energy Concept.

Besharat, M.; Dadfar, A.; Viseu, M.T.; Brunone, B.; Ramos, H.M. Transient-Flow Induced Compressed Air Energy Storage (TI-CAES) System towards New Energy Concept. Water 2020, 12, 601. 

Abstract

In recent years, interest has increased in new renewable energy solutions for climate change mitigation and increasing the efficiency and sustainability of water systems. Hydropower still has the biggest share due to its compatibility, reliability and flexibility.

This study presents one such technology recently examined at Instituto Superior Técnico based on a transient-flow induced compressed air energy storage (TI-CAES) system, which takes advantage of a compressed air vessel (CAV). The CAV can produce extra required pressure head, by compressing air, to be use for either hydropower generation using a water turbine in a gravity system or to be exploited in a pumping system. The results show a controlled behaviour of the system in storing the pressure surge as compressed air inside a vessel.

Considerable power values are achieved as well, while the input work is practically neglected. Higher power values are attained for bigger air volumes.  The TI-CAES offers an efficient and flexible solution that can be exploited in exiting water systems without putting the system at risk. The induced transients in the compressed air allow a constant outflow discharge characteristic, making the energy storage available in the CAV to be used as a pump storage hydropower solution.  

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Improved Planning of Energy Recovery in Water Systems Using a New Analytic Approach to PAT Performance Curves.

Pérez-Sánchez, M.; Sánchez-Romero, F.J.; Ramos, H.M.; López-Jiménez, P.A. Improved Planning of Energy Recovery in Water Systems Using a New Analytic Approach to PAT Performance Curves. Water 2020, 12, 468. 

Abstract

The use of pumps working as turbines (PATs) to improve the energy efficiency of water networks has been studied in the last years. This recovery system is justified due to a low investment contrasting with the capacity to take advantage in certain points with low and medium recoverable heads.

Analyses of water systems using simulation software and/or optimization algorithms need the characteristic curves (head and efficiency) of the machines, which should be known with minor error by the water managers. The knowledge of the best efficiency point (BEP) as a turbine is one of the major limitations when the user wants to choose PATs. In this sense, the present research defines new approach equations to estimate the BEP of the PAT, as well as to predict the characteristic curves, comparing the results with the rest of the published methods.

The comparison demonstrated that the new proposal reduced the error indexes, improved the R2 and increased the accuracy of the error ellipse using an experimental database of 181 different PATs.

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Smart Water Management towards Future Water Sustainable Networks

Ramos, H.M.; McNabola, A.; López-Jiménez, P.A.; Pérez-Sánchez, M. Smart Water Management towards Future Water Sustainable Networks. Water 2020, 12, 58. 

Abstract

Water management towards smart cities is an issue increasingly appreciated under financial and environmental sustainability focus in any water sector. The main objective of this research is to disclose the technological breakthroughs associated with water and energy use.

A methodology is proposed and applied in a case study to analyze the benefits to develop smart water grids, showing the advantages offered by the development of control measures. The case study showed the positive results, particularly savings of 57 GWh and 100 Mm3 in a period of twelve years when different measures from the common ones were developed for the monitoring and control of water losses in smart water management. These savings contributed to reducing the CO2 emissions to 47,385t CO2-eq.

Finally, in order to evaluate the financial effort and savings obtained in this reference systems (RS) network, the investment required in the monitoring and water losses control in a correlation model case (CMC) was estimated, and, as a consequence, the losses level presented a significant reduction towards sustainable values in the next nine years. Since the pressure control is one of the main issues for the reduction of leakage, an estimation of energy production for Portugal is also presented.

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Energy Transfer from the Freshwater to the Wastewater Network Using a PAT-Equipped Turbopump

Morani, M.C.; Carravetta, A.; Fecarotta, O.; McNabola, A. Energy Transfer from the Freshwater to the Wastewater Network Using a PAT-Equipped Turbopump. Water 2020, 12, 38.

Abstract

A new strategy to increase the energy efficiency in a water network exists using turbo pumps, which are systems consisting of a pump and a turbine directly coupled on a same shaft. In a turbo pump, the pump is fed by a turbine that exploits a surplus head in a freshwater network in order to produce energy for one system (wastewater) and reduce the excess pressure in another (drinking water). A pump as turbine (PAT) may be preferred over a classic turbine here due to its lower cost. The result of such a coupling is a PAT–pump turbocharger (P&P).

In this research, the theoretical performance of a P&P plant is employed using data from a real water distribution network to exploit the excess pressure of a freshwater stream and to feed a pump conveying wastewater toward a treatment plant. Therefore, the P&P plant is a mixed PAT–pump turbocharger, operating with both fresh and wastewater. A new method to perform a preliminary geometric selection of the machines constituting the P&P plant has been developed. Furthermore, the plant operation has been described by means of a new mathematical model under different boundary conditions.

Moreover, the economic viability of the plant has been assessed by comparison with a conventional wastewater pumping system working in ON/OFF mode. Therefore, the net present value (NPV) of the investment has been evaluated in both situations for different time periods. According to the economical comparison, the PAT–pump turbocharger represents the most economically advantageous configuration, at least until the useful life of the plant. Such convenience amounts to 175% up to a time period equal to 20 years.

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Zero-net energy management for the monitoring and control of dynamically-partitioned smart water systems.

Giudicianni, C., Herrera, M., di Nardo, A., Carravetta, A., Ramos, H. M., & Adeyeye, K. (2020). Zero-net energy management for the monitoring and control of dynamically-partitioned smart water systems. Journal of Cleaner Production, 119745. 

Abstract

The optimal and sustainable management of water distribution systems still represent an arduous task. In many instances, especially in aging water net-works, pressure management is imperative for reducing breakages and leakages. Therefore, optimal District Metered Areas represent an effective solution to decreasing the overall energy input without performance compromise. Within this context, this paper proposes a novel adaptive management framework for water distribution systems by reconfiguring the original network layout into (dynamic) district metered areas. It utilises a multiscale clustering algorithm to schedule district aggregation/desegregation, whilst delivering energy and supply management goals. The resulting framework was tested in a water utility network for the simultaneously production of energy during the day (by means of the installation of micro-hydropower systems) and for the reduction of water leakage during the night. From computational viewpoint, this was found to significantly reduce the time and complexity during the clustering and the dividing phase. In addition, in this case, a recovered energy potential of 19 MWh per year and leakage reduction of up to 16% was found. The addition of pump-as-turbines was also found to reduce investment and maintenance costs, giving improved reliability to the monitoring stations. The financial analyses to define the optimal period in which to invest also showed the economic feasibility of the proposed solution, which assures, in the analysed case study, a positive annual net income in just five years. This study demonstrates that the combined optimisation, energy recovery and creation of optimized multiple-task district stations lead to an efficient, resilient, sustainable, and low-cost management strategy for water distribution networks.

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Micro hydropower and the water-energy-food nexus

Stocks, C (2020); Micro hydropower and the water-energy-food nexus, NS Energy, January 2020.

Abstract

Researchers Miguel Crespo Chacón and Kemi Adeyeye explain how the European-funded REDAWN project has been developed to explore the water-energy-food nexus, and to investigate how micro hydropower could help improve energy efficiency in the water sector.

 

A life cycle assessment of the construction phase of eleven micro-hydropower installations in the UK

T. Ueda, E.S. Roberts, A. Norton, D. Styles, A.P. Williams, H.M. Ramos, J. Gallagher, (2019), A life cycle assessment of the construction phase of eleven micro-hydropower installations in the UK, Journal of Cleaner Production, Volume 218, 2019, Pages 1-9, ISSN 0959-6526

Abstract

The rapid deployment of renewable energy technologies continues, yet the environmental impacts associated with their construction is accepted without sustainable design considerations. This life cycle assessment study quantifies the embodied burdens in the construction phase of eleven microhydropower installations, ranging from 70-100 kW in size. The consumption of concrete and aggregates, metals and plastics influence each of the five impact categories assessment differently. In relation to global warming potential, upstream production of concrete and aggregates contributed 25-44%, whilst production of plastics contributed 27-49%. For acidification potential, production of metals and plastics contributed 29-67% and 19-45%, respectively. Production of metals used in MHP projects contributed 86-98% of human toxicity potential and 79-98% of abiotic resource depletion, whilst production of plastics contributed 56-77% of fossil resource depletion potential. One low-head scheme had the highest global warming, acidification and fossil resource depletion burdens due to large quantities of materials used in construction, while another scheme demonstrated high human toxicity and abiotic resource depletion burdens due to a 3-km grid connection upgrade for exporting electricity. The results were more sensitive to the quantity of materials used in the micro-hydropower projects than to changes in transport and construction contributions. The use of alternative materials could reduce global warming potential, e.g. a wood-frame powerhouse instead of concrete construction would reduce it by 6-12%. The results also indicated a general trend of reduced burdens per kWh electricity generated as capacity increased. However, no clear correlations were found between site-specific characteristics and environmental impacts in constructing these micro-hydropower projects. Therefore, independent life cycle assessment case studies are still required to inform better construction practices for specific renewable energy projects, with significant potential to improve environmental performance, especially in relation to resource efficiency as per circular economy principles.

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Sustainable water-energy nexus in the optimization of the BBC golf-course using renewable energies

Helena M. Ramos, M. Zilhao, P. Amparo López-Jiménez & Modesto Pérez Sánchez (2019) Sustainable water-energy nexus in the optimization of the BBC golf-course using renewable energies, Urban Water Journal, 16:3, 215-224

Abstract

Water distribution networks and irrigation systems consume high energy quantities that need to be recovered if the water managers want to meet sustainable systems. A sustainability optimization is proposed in this research in order to replace the energy consumption in a golf-course system by renewable solutions joining energy recovery, sustainable urban drainage systems and hybrid solutions (solar panels and wind turbine). Different sustainable approaches were considered in which energy (using PATs), economic and environmental factors were analysed. Both scenarios and analyses showed interesting values related to economic indicators and environmental reductions of CO2 emissions. The possibility to supply the daily electric consumption in the pumping stations was checked using only renewable systems. Net present value was calculated in different solutions, obtaining positive values as well as the payback period was lower than 6 years. The CO2 emissions were reduced from 257,000 to 11,500 kgCO2/year in the most unfavourable scenario.

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Hydropower energy recovery in irrigation networks: Validation of a methodology for flow prediction and pump as turbine selection

Miguel Crespo Chacón, Juan Antonio Rodríguez Díaz, Jorge García Morillo, Aonghus McNabola, Hydropower energy recovery in irrigation networks: Validation of a methodology for flow prediction and pump as turbine selection, Renewable Energy, Volume 147, Part 1, 2020, Pages 1728-1738, ISSN 0960-1481

Abstract

In recent years, pump-as-turbines (PATs) have been highlighted for their potential benefits as an application of micro-hydropower (MHP) in water distribution networks. However, PATs come with disadvantages of relatively low peak efficiencies, which can be reduced further with large flow fluctuations. MHP and PATs in particular applied in irrigation networks is a relatively new area of research focus for these devices, and one that poses significant opportunities for energy saving as well as significant challenges due to variations in flow rate.

This paper discusses the validation of a statistical methodology to estimate the flow and head variability in a network, and to select PATs whose best efficiency point (BEP) returns the lowest payback period. A comparison between the predicted and actual occurrence probabilities for different flow rates was carried out at nine potential points for MHP installation identified within a real network in Southwestern Spain.

For the flow occurrence probability, the coefficient of determination (R2) of 0.804. A total of 281.0 MWh were obtained from the flow prediction and PAT selection methodology, in contrast to 230.5 MWh using the actual measured data. An overall difference of 0.2% was obtained when both PATs were simulated under actual conditions.

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Wastewater Pump Control under Mechanical Wear

Fecarotta, O., Martino, R., & Morani, M. C. (2019). Wastewater Pump Control under Mechanical Wear. Water, 11(6), 1210. 

Abstract:

With reference to a classical wet tank equipped with a wastewater submersible pump, in this research, an advanced numerical model has been used in order to obtain the optimal pump scheduling of on/off operation and variable pump speed. Then, in order to evaluate the time decay of pump performances, the mechanical wear has been artificially simulated and the performance curves have been experimentally obtained for different rotational speeds. Finally, the benefits, as well as the feasibility, of pump scheduling have been evaluated for differing operating conditions. According to the results, the optimal pump scheduling achieves large energy savings up to 43%, for soft mechanical wear. If the mechanical wear is considered, the energy savings are large as well, between 35.60% and 26.70%, for medium and hard mechanical wear, respectively. On the other hand, the limitation of such a strategy has been highlighted: the feasibility of pump scheduling is limited by the elevation of the downstream tank. According to the results, energy savings can be achieved until the elevation of the downstream tank is 67% of the pressure head at the best efficiency point, whereas such percentage decreases to 50% for hard mechanical wear. Finally, the results show that plant efficiency is strongly affected by the mechanical wear: an accurate maintenance of the pumping system is therefore recommended in order to attenuate the time decay of pump performances.

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Optimal energy efficiency of isolated PAT systems by SEIG excitation tuning

João F.P. Fernandes, Modesto Pérez-Sánchez, F. Ferreira da Silva, P. Amparo López-Jiménez, Helena M. Ramos, P.J. Costa Branco, Optimal energy efficiency of isolated PAT systems by SEIG excitation tuning, Energy Conversion and Management, Volume 183, 2019,Pages 391-405

Abstract:

The use of pump working as turbine (PAT) was identified by many researchers as a way to improve the energy efficiency in the water systems. However, the majority of the researches consider the hydraulic machine connected to the electrical grid, which may not fit best when these recovery systems are located in rural or remote areas. To improve the efficiency in these recovery systems for rural areas, this research contributes for a further study and optimization of the off-grid PAT systems with induction generators. The current manuscript proposes a methodology to obtain the best efficiency of the PAT-SEIG (Self-Excited Induction Generator) system when operating under different speeds and loads. For these systems, the selection of capacitors for the SEIG is critical to maximizing the energy efficiency. A methodology is proposed to estimate and select the correct SEIG model parameters and, thus, compute the best capacitor values to improve the PAT-SEIG energy efficiency. Special attention is given to the impact the SEIG parameters have in the efficiency of the recovery system. The accuracy of the analytical model improved, reducing the error between analytical and experimental results from 50.8% (for a model with constant parameters) to 13.2% (with parameters changing according to the operating point of the system). These results showed an increase of the overall PAT system efficiency from 26% to 40% for the analyzed case study.

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Flow Conditions for PATs Operating in Parallel: Experimental and Numerical Analyses

Simão, M.; Pérez-Sánchez, M.; Carravetta, A.; Ramos, H.M. Flow Conditions for PATs Operating in Parallel: Experimental and Numerical Analyses. Energies 2019, 12, 901.

Abstract

Micro-hydro systems can be used as a promising new source of renewable energy generation, requiring a low investment cost of hydraulic, mechanical, and electrical equipment.

The improvement of the water management associated with the use of pumps working as turbines (PATs) is a real advantage when the availability of these machines is considered for a wide range of flow rates and heads. Parallel turbomachines can be used to optimize the flow management of the system. In the present study, experimental tests were performed in two equal PATs working in parallel and in single mode. These results were used to calibrate and validate the numerical simulations.

The analysis of pressure variation and head losses was evaluated during steady state conditions using different numerical models (1D and 3D). From the 1D model, the installation curve of the system was able to be defined and used to calculate the operating point of the two PATs running in parallel.

As for the computational fluid dynamics (CFD) model, intensive analysis was carried out to predict
the PATs behavior under different flow conditions and to evaluate the different head losses detected within the impellers. The results show system performance differences between two units running in parallel against a single unit, providing a greater operational flow range. 

The performance in parallel design conditions show a peak efficiency with less shock losses within the impeller. Furthermore, by combining multiple PATs in parallel arrangement, a site’s efficiency increases, covering a wide range of applications from the minimum to the maximum flow rate. The simulated flow rates were in good agreement with the measured data, presenting an average error of 10%.

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Cost Model for Pumps as Turbines in Run-of-River and In-Pipe Microhydropower Applications

D. Novara; A. Carravetta; A. McNabola; and H. M. Ramos, Cost Model for Pumps as Turbines in Run-of-River and In-Pipe Microhydropower Applications, Journal of Water Resources Planning and Management, Vol. 145, Issue 5 (May 2019), ISSN (print): 0733-9496 | ISSN (online): 1943-5452

Abstract

Pumps as Turbines (PATs) are standard water pumps utilized as hydraulic turbines by reversing the flow direction across them. The off-the-shelf availability of water pumps and their reduced purchase price with respect to conventional hydro turbines makes them an ideal technology for exploiting large portions of uncapped hydro potential that is technically viable but not financially convenient.

Such low-cost technology could help to expand hydropower exploitation in water resources worldwide, helping to reduce climate change greenhouse gas emissions. However, in the literature, the few available cost figures relative to PAT purchase price are discordant and often outdated, and such a lack of information is likely a severe barrier to a more widespread PAT implementation.

In order to overcome this limitation, data from 343 pumps and 286 generators were compiled to show graphically and analytically how the purchase price of PATs varies over different nominal powers and hydraulic conditions. Besides, a set of equations was developed to allow designers to predict the PAT and generator cost from the nominal flow rate and available hydraulic head.

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Pump-as-Turbine Selection Methodology for Energy Recovery in Irrigation Networks: Minimising the Payback Period

Miguel Crespo Chacón, Juan Antonio Rodríguez Díaz, Jorge García Morillo and Aonghus McNabola,
Pump-as-Turbine Selection Methodology for Energy Recovery in Irrigation Networks: Minimising the Payback Period (2019),
Water 2019, 11(1), 149 

Abstract

In pressurized irrigation networks, energy reaches around 40% of the total water costs. Pump-as-Turbines (PATs) are a cost-effective technology for energy recovery, although they can present low efficiencies when operating outside of the best efficiency point (BEP). Flow fluctuations are very important in on-demand irrigation networks. This makes flow prediction and the selection of the optimal PAT more complex. In this research, an advanced statistical methodology was developed, which predicts the monthly flow fluctuations and the duration of each flow value. This was used to estimate the monthly time for which a PAT would work under BEP conditions and the time for which it would work with lower efficiencies. In addition, the optimal PAT power for each Excess Pressure Point (EPP) studied was determined following the strategy of minimising the PAT investment payback period (PP). The methodology was tested in Sector VII of the right bank of the Bembézar River (BMD), in Southern Spain. Five potential sites for PAT installation were found. The results showed a potential energy recovery of 93.9 MWh and an annual energy index per irrigated surface area of 0.10 MWh year−1 ha−1. Renewable energy will become increasingly important in the agriculture sector, to reduce both water costs and the contribution to climate change. PATs represent an attractive technology that can help achieve such goals.

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Flow Velocity Distribution Towards Flowmeter Accuracy: CFD, UDV, and Field Tests

Mariana Simão, Mohsen Besharat, Armando Carravetta and Helena M. Ramos,  (2018) Flow Velocity Distribution Towards Flowmeter Accuracy: CFD, UDV, and Field Tests, Water 2018, 10, 1807; doi:10.3390/w10121807

Abstract

Inconsistences regarding flow measurements in real hydraulic circuits have been detected. Intensive studies stated that these errors are mostly associated to flowmeters, and the low accuracy is connected to the perturbations induced by the system layout. In order to verify the source of this problem, and assess the hypotheses drawn by operator experts, a computational fluid dynamics (CFD) model, COMSOL Multiphysics 4.3.b, was used. To validate the results provided by the numerical model, intensive experimental campaigns were developed using ultrasonic Doppler velocimetry (UDV) as calibration, and a pumping station was simulated using as boundary conditions the values measured in situ. After calibrated and validated, a new layout/geometry was proposed in order to mitigate the observed perturbations. 

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A Comparison of Energy Recovery by PATs against Direct Variable Speed Pumping in Water Distribution Networks

Maria Cristina Morani, Armando Carravetta, Giuseppe Del Giudice, Aonghus McNabola and Oreste Fecarotta; A Comparison of Energy Recovery by PATs against Direct Variable Speed Pumping in Water Distribution Networks; Fluids 2018, 3(2), 41; doi:10.3390/fluids3020041

Hydro-power energy recovery in pressurized irrigation networks

Garcia Morillo, J., McNabola, A., Camacho, E., Montesisnos, P., Rodriguez-Diaz, J.A., Hydro-power energy recovery in pressurized irrigation networks: A case study of an Irrigation District in the South of Spain., Agricultural Water Management, 204, 2018, p17 - 27

Electrical behaviour of the pump working as turbine in off grid operation

Capelo, B; Pérez-Sánchez, M; Fernandes, JFP; Ramos, H.M; López-Jiménez, P.A; Costa Branco, P.J. Electrical behaviour of the pump working as turbine in off grid operation, Applied Energy 2017, 208, 302-311

CFD Analyses and Experiments in a PAT Modeling

Pérez-Sánchez, M.; Simão, M.; López-Jiménez, P.A.; Ramos, H.M. CFD Analyses and Experiments in a PAT Modeling: Pressure Variation and System Efficiency. Fluids 2017, 2, 51.

Urban Floods Adaptation and Sustainable Drainage Measures

Ramos, H.M.; Pérez-Sánchez, M.; Franco, A.B.; López-Jiménez, P.A. Urban Floods Adaptation and Sustainable Drainage Measures. Fluids 2017, 2, 61.

Velocities in a Centrifugal PAT Operation: Experiments and CFD Analyses

Simão M, Pérez-Sánchez M, Carravetta A, López-Jiménez P, Ramos HM. Velocities in a Centrifugal PAT Operation: Experiments and CFD Analyses. Fluids. 2018; 3(1):3.

Books

REDAWN Report: WP5 Environmental Impact Assessment

A reference document for project developers for environmental impact assessment of energy recovery projects

To address the growing demand for energy and water at affordable costs and in an environmentally sustainable manner, it is necessary to understand the availability of resources and to develop technologies to reduce their consumption and to make their use sustainable. In this sense, EU policies are directed to:

  • Reduce energy consumption in water management systems (supply, purification, sanitation) through improved energy and hydraulic efficiency.
  • Recover energy from water flows in hydraulic infrastructures by means of small hydroelectric solutions.
  • Reduce water consumption in energy production.

The main objective of the REDAWN Project focuses on the second challenge, trying to consolidate a new water-energy management model more sustainable, and promoting the installation of micro-hydro devices in hydraulic infrastructures of the European countries in the Atlantic area.

The present study is divided into three parts. The first part is a summary of the analysis of the energy potential in the main hydraulic infrastructures located in countries in the Atlantic Area, including an identification of optimal sites to install micro-hydro devices.

Those infrastructures are:

  • Urban and industrial wastewater networks, including sewage treatment plants.
  • Drinking water supply networks, including water potabilization plants.
  • Irrigation infrastructures. 

The second part is an evaluation of possible environmental impacts that could take place in these hydraulic infrastructures during its operation.

The third part is an evaluation of potential environmental benefits that could result from the integration of micro-hydro devices in those hydraulic infrastructures. The analysis includes commissioning and operative phases.

Although an exhaustive analysis will be done in the following sections, some positive effects can be now identified:

  • GHG emissions from electrical production will be reduced. This has a direct impact in global warming and climate change.
  • Generation of polluting waste will be avoided while the system is working.
  • Once the new equipment has been introduced, the circulating water properties won´t be altered.  
  • It fits in a smaller space than the traditional hydroelectric plants, which means a smaller civil work and a reduction of the environmental impact.

The aim of this study is not just to get a general vision of the environmental effects, but to create a reference document for potential project developers for their own environmental assessments.

Download the full text of the report here (pdf)

REDAWN Report: WP5 Economic Feasibility Assessment

A comprehensive assessment of the economic benefits that the installation of MHPs could have for water companies.

The objective of the REDAWN project is to reduce the energy dependancy of water networks in the Atlantic area (AA), improving the energy efficiency of water networks through the use of micro-hydropower (MHP) technology. The energy consumption linked to the water industry is such that it is responsible for significant contributions to climate change, thus, some measures are needed to transform the sector into a more sustainable system. Potential energy recovery from micro-hydropower plants (MHP), using small-scale traditional turbines and pump-as-turbines (PATs), present an option to reduce this energy consumption. These are being assessed in the REDAWN project across public drinking water networks, private industrial water networks, waste water networks, and irrigation networks are investigated.

The introduction of MHP in water networks will have an economic impact in water activity. This effect not only supposes a potential reduction of costs due to a self-consumption of the electricity generated but also a potential increase in the competitiveness of the management of the network thanks to the access to electricity in isolated areas where electrical devices could be used to improve the management of the grid.

More specifically, this economic feasibility assessment will comprise three parts:  

  • A summary of the analysis of the energy potential in the main hydraulic infrastructures located in countries in the Atlantic Area, including an identification of optimal sites to install micro-hydro devices.
  • An evaluation of economic conditions that can affect the viability of a MHP in order to define their economic profitability.
  • Quantification of the potential economic impact of the exploitation of the available sites identified for hydropower exploitation in the project. 

The work will include the impact of MHP energy recovery on the operating energy costs of water supply, waste water treatment, irrigation, and process industry.

Download the full text of the report here (pdf)

The Northern Ireland experience in Transnational Programmes

SEUPB brochureThis review by the Special EU Programmes Body provides an overview of the INTERREG VB Transnational / VC Interregional Programmes, featuring some of the many achievements which have been made within Northern Ireland.  This includes the REDAWN project.

From blue growth and green mobility, to remote area connectivity, ageing populations and migration, Interreg transnational cooperation is fostering strong partnerships where national, regional & local authorities; academia; NGOs;and private sector enterprises work together to tackle today’s complex challenges. These multi-sector alliances build on regional strengths and address real challenges facing real places and people across Europe.

Download a pdf of the brochure here

#EU in my region: 30 years of Partnership: Stories of Countries & Regions Sharing Knowledge, Ideas & Innovation

#EU in my region brochureIt is impossible to capture the full extent and impact of Interreg programmes but in these pages you can enjoy a snapshot of projects supported by the Atlantic Area Programme, Northern Periphery and Arctic Programme and Interreg Europe, including REDAWN.

More than four decades have now elapsed since Ireland joined what was then the Common Market in 1973.

Throughout that period, Ireland has been a major beneficiary of EU Cohesion funding. The Union’s Cohesion policy lies at the heart of European integration and solidarity and proves that these words have real meaning for every part of the Union. It has been one of Europe’s success stories.

Everywhere you travel in Ireland you can see the distinctive Structural Funds logo on plaques and signs, which highlights the many ways we have benefitted from Cohesion funding – from major infrastructure road and rail projects to smaller community projects, to projects aimed at helping people acquire new skills and find better jobs. All serve to underline the very real ways Ireland has benefitted from its membership of the European Union. 

But Cohesion funding has done more than that. It has enabled Ireland to take part in European Territorial Cooperation – or INTERREG - programmes with other Member States and neighbouring countries.

Download a pdf of the brochure here

Pumps as Turbines: Fundamentals and Applications

Carravetta, A;  Houreh, S.D; Ramos, H.M. Pumps as Turbines: Fundamentals and Applications, Springer, 2018.

This book provides users, pump manufactures, engineers, researchers and students with extensive information about pump’s behavior in reverse operation. It reports on cutting-edge methods for selecting the proper PAT and improving PAT’s efficiency, discusses PAT’s reliability, economic issues and environmental impact as well. The book describes in detail electromechanical equipment of PAT systems, their installation and operation, and gives important practical insight into the use of PAT in water transmission and distribution systems, as part of thermal power plants and cooling systems, in oil distribution systems and other systems as well. It reports on different types on PAT control modes as well as on numerical methods useful for PAT analysis and implementation.  All in all, the book represents a comprehensive practice-oriented reference-guide to design engineers, as well as PAT general users and manufactures. It also provides researchers with extensive technical information on the use of PAT thus fostering new discussions and ideas to improve current methods and cope with future challenges.

Conference Proceedings

Reducing the Energy Dependency of Water Networks in Irrigation, Public Drinking Water, and Process Industry: REDAWN Project.

Carravetta, A.; Fecarotta, O.; Ramos, H.M.; Mello, M.; Rodriguez-Diaz, J.A.; Morillo, J.G.; Adeyeye, K.; Coughlan, P.; Gallagher, J.; McNabola, A. Reducing the Energy Dependency of Water Networks in Irrigation, Public Drinking Water, and Process Industry: REDAWN Project. Proceedings 2018, 2, 681.

https://doi.org/10.3390/proceedings2110681

Energy Saving Measures in Pressurized Irrigation Networks: A New Challenge for Power Generation.

Morillo, J.G.; Díaz, J.A.R.; Crespo, M.; McNabola, A. Energy Saving Measures in Pressurized Irrigation Networks: A New Challenge for Power Generation. Proceedings 20182, 1440.

https://doi.org/10.3390/proceedings2231440

Fostering Renewable Energies and Energy Efficiency in the Water Sector Using PATs and Wheels

Ramos, H.M.; Simão, M.; McNabola, A.; Novara, D.; Carravetta, A. Fostering Renewable Energies and Energy Efficiency in the Water Sector Using PATs and Wheels. Proceedings 2018, 2, 1438.

http://www.mdpi.com/2504-3900/2/23/1438/pdf

Energy recovery using PAT

Simão, M., Besharat, M. ,Ramos, H.M; (2018) Energy recovery using PAT,  Silva-Afonso A and Rodrigues-Pimental, C. (Eds), Proceedings of the Water Efficiency Conference 2018, 5-7 September 2018, Aveiro Portugal: WATEF Network/ University of Bath.

 

Hydropower energy recovery in water pipe networks: spatial regression analysis using GIS, assessing the correlation between energy recovery potential and geographical data

Dorde Mitrovic, Juan Antonio Rodriguez Diaz, Jorge Garcia Morillo, Paul Coughlan, John Gallagher, Aonghus McNabola, (2018) Hydropower energy recovery in water pipe networks: spatial regression analysis using GIS, assessing the correlation between energy recovery potential and geographical data, Silva-Afonso A and Rodrigues-Pimental, C. (Eds), Proceedings of the Water Efficiency Conference 2018, 5-7 September 2018, Aveiro Portugal: WATEF Network/ University of Bath.

Reducing the Energy Dependency of Water Pipe Networks in the Atlantic Area of Europe

Carravetta, A, Fecarotta, O., Ramos, H.M, Mello, M., Rodriguez-Diaz, J.A., Garica-Morillo, J., Adeyeye, K., Coughlan, P., Gallagher, J., McNabola, A., Reducing the Energy Dependency of Water Pipe Networks in the Atlantic Area of Europe: Case studies in irrigation, public drinking water and process industry, 3rd International EWaS (Efficient Water Systems) Conference, Greece, 27-30 June, 2018, pp1-7

Potential Energy Recovery using Micro-Hydropower Technology in Irrigation Networks

Crespo Chacon M., Rodriguez Diaz JA., Garcia Morillo J., Gallagher J., Coughlan P., McNabola A., Potential Energy Recovery using Micro-Hydropower Technology in Irrigation Networks: Real-World Cases Studies in the South of Spain, 3rd International EWaS (Efficient Water Systems) Conference, Greece, 27-30 June, 2018, pp1-8

Posters

Hydropower energy recovery potential from irrigation networks

M. Crespo*, A. McNabola, Hydropower energy recovery potential from irrigation networks, Presented at ENVIRON2018, Cork, Ireland.

Hydropower energy recovery potential of water distribution networks

D. Mitrovic*, A. McNabola, Hydropower energy recovery potential of water distribution networks: Assessing the correlation between the potential and geographical data, Presented at ENVIRON2018, Cork, Ireland.

Presentations

Hydropower energy recovery in water pipe networks

Potential Energy Recovery using MHP in Irrigation Networks: Case studies in Southern Spain