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The energy used to pump and treat water for residents and industry represents between-and 3% of the world's energy consumption {1}. The consumption can be reduced by 25% trough solutions like micro-hydropower (MHP). Pressure reducing valve (PRV) are installed in the water distribution network (WDN) to reduce the leakage losses, which is directly related to the pressure in pipe {2}. The reducing of pressure in PRVs lead to hydraulic losses into thermal losses, replace PRV with MHP system is a good solution to recover a part of those losses. On the other hand, the transport area, with thermal motor, is one of the main issues for slowing the global warming. Replace thermal motor with electrical motor supplied by fuel cells is a good solution. One of the biggest water tanks in Rennes (France) called "Les Gallets" is an interesting site to implement MHP installation, the huge site area allows to implement a electrolyze installation to supply hydrogen cars. Coupling the production of hydrogen with MHP system is a solution to get a green energy production. The scheme of the installation is presented in figure 1. The site "Les Gallets" is composed of two water tanks, one is called "Les Gallets Haut", the other one is called "Les Gallets Bas". Two MHP systems can be installed, one upstream the first water tank, and one between both water tanks. Conventional turbines are not massively available on the market, hence they are expensive and lead to strong payback periods for MHP, to face this problem, the use of pumps in reverse mode (pumps as turbines) is a solution {3}. Indeed, those pumps have a good accuracy (between 50 to 85%) and can divided by 10 times the payback period of an installation compared to conventional turbines installations. For this study, an average efficiency of 65% for Pumps as turbines installations is considered. Flow conditions of both installations are detailed in table 1. Site Flow rate (l/s) Head (m) Load factor (h/year) E lost (MWh/year) Producible (MWh/year) H 2 Producible (kg H 2 /year)

International audience; Inverted organic photovoltaic cells (IOPVCs), based on the planar heterojunction C60/CuPc, were grown using MoO3 as anode buffer layer and CsI or Cs2CO3 as cathode buffer layer (CBL), the cathode being an ITO coated glass. Work functions, Φf, of treated cathode were estimated using the cyclic voltammetry method. It is shown that Φf of ITO covered with a Cs compounds is decreased. This decrease is amplified by the annealing. It is shown that the thermal deposition under vacuum of the CBL induces a partial decomposition of the caesium compounds. In parallel, the formation of a compound with the In of ITO is put in evidence. This reaction is amplified by annealing, which allows obtaining IOPVCs with improved efficiency. The optimum annealing conditions is 150 °C for 5 min.