Barrons AP Environmental Science

Figure  8.9 Diagram of  a   nuclear power   plant

A.  CORE—contains   up  to  50,000  fuel    rods.   Each    fuel    rod is  stacked with

many    fuel    pellets;    each    pellet  has the energy  equivalent  of  1   ton (0.9    m.t.)

of  coal    or  17,000  ft^3    (481    m^3 )   of  natural gas or  149 gallons (564    L)  of  oil.

B.  FUEL—enriched   (concentrated)  U-235   is  usually the fuel.   The fission of

an  atom    of  uranium produces    10  million times   the energy  produced    by  the

combustion  of  an  atom    of  carbon  from    coal.

C.  CONTROL RODS—move   in  and out of  the core    to  absorb  neutrons    and slow

down    the reaction.

D.  MODERATOR—reduces   the speed   of  fast    neutrons,   thereby allowing    a

sustainable chain   reaction.   Can be  water,  graphite    (which  can produce

plutonium   for weapons),   or  deuterium   oxide   (heavy  water   H 2 O).

Deuterium   is  an  isotope of  hydrogen    whose   nucleus comprises   both    a

neutron and a   proton; the nucleus of  a   protium (normal hydrogen)   atom

consists    of  just    a   proton.

E.  COOLANT—removes heat    and produces    steam   to  generate    electricity.

Pros

■ Nuclear   energy  produces    62% of  all U.S.    emission-free   electricity.

■ Releases  about   one-sixth   the CO 2    that    fossil-fuel plants  do, thus    reducing

global  warming.