An Introduction to Micro-Hydro Electric Power
[Micro-HEP]
Micro-HEP are water turbines with a rated power output of less than 100kW
Three Types of HEP Installations
• High Head – Using water from high up stored water such as a Highland Loch
• Medium Head – Using impounded water. • Low Head – ‘Run of the River’. No stored
water
Stages from Idea to Installation
• Desktop Study • Pre-Feasibility Study • Feasibility Study • Recommendation • Planning Permission • Abstraction Licence• Civil Works • Installation & Commissioning.
Simple Calculation to Assess HEP Potential
• 6 x Head [m] x Flow Rate [m³/s] = Power [kW]
• High head systems need little water flow to generate significant power
• Low head systems need plenty of water
Income & Returns on Investment
of HydroElectric Power• HEP tends to be more expensive to install than wind turbines or PV due to the cost of civil works.
• The power production of HEP is about double that of a wind turbine for the rated system, as the system runs all the time between known flow rates.
• The FiT rate is 19.31p/kWh plus export tariff [<15kW installation to April 2016]
• Hydro schemes should last more than fifty years.
Pitfalls
• The planning process can be long and frustrating.
• The Abstraction Licence process can be long and frustrating.
• The development may require a fish pass /eel pass, which may add to the civil work costs.
• Flood Prevention• Remote sites will have expensive
electrical grid connections.
Example of a Low Head 90kW, £800k Project
• Two 45kW Axial Turbines.• EA installed fish pass• Generates 400MWh/year• Income £100,000 / year
Example of a 10kW £60k Medium Head system
• Cross Flow turbine
• Lake sediment trap restoration
• Generates 30,000 kWh/year
• Installation total cost £72k
Example of a 8kW £90k low head project
• Breast shot water wheel.• Eel & Fish Pass• Generates 27,000 kWh output
Example of a High Head £80k project
• Pelton Wheel turbine
• 150m Head• 30kW output• Six year payback