Environmental Engineering Reference
In-Depth Information
3
Pumped Hy
droelectric Energy Storage
JonahG.Levine
CONTENTS
Basic Concepts ....................................................................................................... 51
Value of PHES to Interconnected Electricity Systems...................................... 51
Example: Dominion Power's Bath County PHES Station .............................. 53
PHES Efficiency ..................................................................................................... 54
Facilities in United States ..................................................................................... 54
Energy and Power Potential ................................................................................ 54
Development.......................................................................................................... 61
Environmental Considerations ...................................................................... 63
System Components ........................................................................................ 63
Reservoirs ..................................................................................................... 63
Waterways .................................................................................................... 67
Impulse Turbines and Centrifugal Pumps............................................... 71
References............................................................................................................... 75
BasicConcepts
Pumped hydroelectric energy storage (PHES) technology allows utilities to store
generated energy that may become a load on demand within the constraints of
the particular facility. Energy is stored as the potential of water raised against
gravity. Stated simply, water is pumped through a turbine from a lower reser-
voir (afterbay) to a higher reservoir (forebay) and the activity uses energy. When
it is desirable to have that energy or water returned, the water is allowed to flow
back through a turbine from the higher reservoir (forebay) to the lower reservoir
(afterbay) and vice versa. Figure 3.1 is a simple line drawing of a PHES facility.
ValueofPHEStoInterconnectedElectricitySystems
As the world embarks on a new era of distributed and at times nondispatch-
able electrical energy systems, the ability to manage increased levels of
