This paper deals with the estimation of the energy potential of pumps used as turbines to exploit residual hydraulic energy, as in the case of available head and flow rate in water distribution networks. To this aim, four pumps with different characteristics are investigated to estimate the producible yearly electric energy. The performance curves of Pumps As Turbines (PATs), which relate head, power and efficiency to the volume flow rate over the entire PAT operation range, were derived by using published experimental data. The three considered water distribution networks, for which experimental data taken during one year were available, are characterized by significantly different hydraulic features (average flow rate in the range 10 – 116 l/s; average pressure reduction in the range 12 - 53 m). Therefore, energy potential estimation accounts for actual flow rate and head variability over the year. The conversion efficiency is also estimated, for both the whole water distribution network and the PAT alone. Finally, a rule of thumb is established in order to select the optimal pump to be used as a PAT, as a function of the characteristics of the considered water distribution network. The results presented in this paper can be used as a guideline for a preliminary evaluation of energy and economic feasibility of PATs aimed to exploit the hydraulic energy potential of water distribution networks.
Energy potential of pumps as turbines (PATs) in water distribution networks
VENTURINI, Mauro;ALVISI, Stefano;SIMANI, Silvio
2015
Abstract
This paper deals with the estimation of the energy potential of pumps used as turbines to exploit residual hydraulic energy, as in the case of available head and flow rate in water distribution networks. To this aim, four pumps with different characteristics are investigated to estimate the producible yearly electric energy. The performance curves of Pumps As Turbines (PATs), which relate head, power and efficiency to the volume flow rate over the entire PAT operation range, were derived by using published experimental data. The three considered water distribution networks, for which experimental data taken during one year were available, are characterized by significantly different hydraulic features (average flow rate in the range 10 – 116 l/s; average pressure reduction in the range 12 - 53 m). Therefore, energy potential estimation accounts for actual flow rate and head variability over the year. The conversion efficiency is also estimated, for both the whole water distribution network and the PAT alone. Finally, a rule of thumb is established in order to select the optimal pump to be used as a PAT, as a function of the characteristics of the considered water distribution network. The results presented in this paper can be used as a guideline for a preliminary evaluation of energy and economic feasibility of PATs aimed to exploit the hydraulic energy potential of water distribution networks.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.