Objectives
     Objectives
     • Review basics of 
         Review basics of 
         Small Hydro systems
         Small Hydro systems
     • Illustrate key considerations for
         Illustrate key considerations for
         Small Hydro project analysis
         Small Hydro project analysis
                                        ®
     •                                  ®
         Introduce RETScreen  Small Hydro Project Model
         Introduce RETScreen  Small Hydro Project Model
                                                                   © Minister of Natural Resources Canada 2001 – 2002.
     What do Small Hydro systems 
      What do Small Hydro systems 
     provide?
      provide?
     • Electricity for
          Electricity for
            Central-grids
            Isolated-grids
            Remote power supplies
     …but also…
            Reliability                                                   Photo Credit: Robin Hughes/ PNS
            Very low operating costs
            Reduced exposure to energy price 
               volatility
                                                                        © Minister of Natural Resources Canada 2001 – 2002.
     Small Hydro System 
     Small Hydro System 
     Description
     Description
                                                                   © Minister of Natural Resources Canada 2001 – 2002.
     “Small” Hydro Projects
     “Small” Hydro Projects
       • “Small” is not universally defined
           “Small” is not universally defined
             Size of project related not just to electrical capacity but also 
               to whether low or high head
                           Typical                         ®                     ®
                                               RETScreen             RETScreen  
                            Power                  Flow           Runner Diameter
                                                        3
        Micro             < 100 kW              < 0.4 m /s             < 0.3 m
                                                           3
                       100 to 1,000 kW       0.4 to 12.8 m /s        0.3 to 0.8 m
        Mini                         
                                                         3
        Small             1 to 50 MW            > 12.8 m /s            > 0.8 m
                                                                   © Minister of Natural Resources Canada 2001 – 2002.
      Types of Small Hydro 
       Types of Small Hydro 
      Projects
       Projects
      • Type of grid                                                      17.6-MW Run-of-River Hydro Project,
            Type of grid
                                                                                   Massachusetts, USA
              Central-grid
              Isolated-grid or off-grid
      • Type of civil works
            Type of civil works
              Run-of-river
                                                                                      Photo Credit: PG&E National Energy Group/
                                                                                            Low Impact Hydropower Institute
                     No water storage
                                                                           4.3-MW Run-of-River Hydro Project,
                     Power varies with flow available                                Oregon, USA
                      from river: lower firm capacity
              Reservoir
                     Higher firm capacity year round 
                     Significant damming usually 
                      required
                                                                      Photo Credit: Frontier Technology/ Low Impact Hydropower Institute
                                                                                      © Minister of Natural Resources Canada 2001 – 2002.