Hydropower Generation for Sustainable and Efficient Buildings: the Wise-buildings Project

The need to produce energy in a sustainable way is an important task to be tackled to improve both human life and environment health. Over time, the development of new energy systems through the exploitation of different available natural sources has been carried on. Nowadays, the efforts of the scientific community are addressed at finding ways to produce clean energy and reduce the carbon production. The use of water was one of the first methods for energy production. Hydraulic resources constitute a huge source of clean and renewable energy which can be managed in several ways, moving from the large-scale to the small-scale plants. However, high plant costs associated with the use of traditional turbines have discouraged the exploitation of small water reserves in the past.

WISE-Buildings (Water In Sustainable and Efficient Buildings) is a recent project, hosted by the Laboratory of Hydraulics and Maritime Constructions of the Università Politecnica delle Marche (Italy), that aims at harvesting energy from conventional urban/domestic systems to reduce building footprint, in terms of water/wastewater and energy consumption. This paper focuses on the use of centrifugal pumps operating as turbines (PATs), installed in water distribution grids to reduce the excessive pressure (and, consequently, the risk of leakage) occurring in water supply systems, while exploiting it to produce energy. Hence, PATs are a suitable alternative for small-hydropower plants and make possible to reduce both design and maintenance costs, since they are cheaper than traditional turbines and spare parts are largely diffused on the market. The purpose of this work is to find appropriate and efficient solutions to produce energy for real-world contexts (e.g. single sparse buildings or small urban agglomerates), while reducing water leakages. In the proposed experimental investigation, a centrifugal pump is selected to operate in reverse mode in different working conditions of pressure and discharge, with the aim to determine its performances, efficiency curves and produced power. Preliminary analyses are also foreseen to evaluate the economic feasibility and environmental impact of the plant.