HEP

Question 1

Features of HEP

Answer 1

renewable, specific local constraints, high embodied energy

Question 2

Hydroelectric power

Answer 2

A method of generating electricity using the downhill flow of water to turn turbines and generators.

Question 3

High head HEP

Answer 3

drop of water greater than 100 metres, often a smaller volume of water.

Question 4

Low head HEP

Answer 4

drop of water typically less than 20 metres, usually a large volume of water

Question 5

Types of low head turbines

Answer 5

Waterwheels, Kaplan turbines, Helical turbines

Question 6

Types of high head turbines

Answer 6

Pelton turbines, Francis turbines

Question 7

Micro-hydro schemes

Answer 7

small scale HEP, often rural community projects. Part of the river is diverted, do not create a barrier across the whole river.

Question 8

Requirements for HEP

Answer 8

large water catchment, high total rainfall all year round, low water turbidity, valley with narrow exit, impermeable rock, low seismic activity, no land use conflict/designation

Question 9

Environmental impacts of HEP

Answer 9

construction of dam (embodied energy), loss of habitat upstream, loss of freshwater habitat downstream, migration barrier, sedimentation behind dam, loss of nutrients downstream, microclimate created due to high specific heat capacity of the reservoir water

Question 10

Pumped storage HEP

Answer 10

An energy storage system where surplus electricity is used to pump water from a lower reservoir to a higher one. The energy stored as gravitational potential energy is allowed to flow downhill to generate electricity during periods of high electricity demand.