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