Electric Power Generation, Transmission, and Distribution

based. Figure 7.1 is a listing of different technologies, their size ranges, fuel sources, and AC interface
type, and most likely applications.

7.2 Fuel Cells

Fuel cell technology has been around since its invention by William Grove in 1839. From the 1960s to
the present, fuel cells have been the power source used for space flight missions. Unlike other generation
technologies, fuel cells act like continuously fueled batteries, producing direct current (DC) by using
an electrochemical process. The basic design of all fuel cells consists of an anode, electrolyte, and
cathode. Hydrogen or a hydrogen-rich fuel gas is passed over the anode, and oxygen or air is passed
over the cathode. A chemical combination then takes place producing a constant supply of electrons
(DC current) with by-products of water, carbon dioxide, and heat. The DC power can be used directly or
it can be fed to a power conditioner and converted to AC power (see Fig. 7.2).

Technology Size Fuel Sources AC Interface Type Applications

Fuel Cells

Microturbines

Batteries

Flywheel

PV

Gas Turbine

.5Kw–

Larger units

With Stacking

10Kw-100Kw

Larger sizes

.1Kw-2Mw+

>.1Kw-.5Kw

>.1Kw-1Kw

10Kw–5Mw+

Natural Gas

Hydrogen

Petroleum Products

Inverter type Continuous

Continuous

Standby

PQ, Peaking

PQ, Peaking

Peaking

Continuous,

Peaking

Standby

Inverter type

Inverter type

Inverter type

Inverter type

Rotary type

Natural Gas

Petroleum Products

Storage

Storage

Sunlight

Natural Gas

Petroleum Products

FIGURE 7.1 Distributed generation technology chart.

Hydrogen (H 2 )

H 2 O, CO 2 and Heat

DC Current Flow

anode Air (O 2 , CO 2 )

Electrons

cathode

electrolyte

FIGURE 7.2 Basic fuel cell operation.