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15.3  Energy  Resources  

Pg  462-­‐466  Notebook  page  117  

Nonrenewable  Energy  Resources  

•  Exist  in  limited  in  quanDDes  and  once  used  cannot  be  replaced  except  over  the  course  of  millions  of  years  

• Nonrenewable  resources  include  oil,  natural  gas,  coal  and  uranium  

Fossil  fuels  

•  Fossil  fuels  -­‐  formed  underground  from  the  remains  of  once-­‐living  organisms.    

•  A  hydrocarbon  deposit,  such  as  petroleum  (oil),  coal,  or  natural  gas  –  formed  by  the  decomposiDon  of  prehistoric  organisms  

•  Are  the  majority  of  the  world’s  energy  source  

•  Are  NOT  found  everywhere  

http://www.wrongtees.com/product.php/11/fossil_fuels

Fossil  Fuels  •  The  US  provides:  

–   2  %  of  the  world’s  oil  supply  – 25%  of  the  world’s  coal  supply  

•  Good  things  – RelaDvely  inexpensive    – Usually  readily  available  

•  Bad  things  – Their  use  creates  polluDon    – We  don’t  have  much  in  the  US  

Renewable  Energy  Resources  

•  Resources  that  can  be  replaced  in  a  relaDvely  short  period  of  Dme  

•  MOST  originate  directly  or  indirectly  from  the  sun.  •  Renewable  energy  resources  include  hydroelectric,  solar,  geothermal,  wind,  biomass,  and  possibly  in  the  future  nuclear  fusion.  

Renewable  Energy  Resources  

•  Include:  – Hydroelectric    – Solar  – Geothermal  – Wind  – Biomass  – Nuclear  Fusion    (possibly  in  the  future)  

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Hydroelectric  Energy  •  Energy  obtained  from  flowing  water  •  As  water  flows  downhill,  its  GPE  is  converted  into  KE.      

•  The  KE  is  used  to  turn  turbines  connected  to  electric  generators  

•  Good  things  – Low  cost  to  produce  and  lack  of  polluDon  

•  Some  bad  things  – Use  dams  which  blocks  the  flow  of  water  and  cause  a  variety  of  environmental  problems  

•  Hamper  the  run  of  fish  upriver  for  spawning  

Hydroelectric  power  plants  

• Some  used  as  water  flows  naturally  down  hill  

• Some  use  dams  to  build  and  hold  back  the  water  to  create  energy  

Solar  Energy    • Sunlight  converted  into  usable  energy  

• Passive  Solar:    like  light  going  through  the  window  

 

AcDve  Solar:  

• Sun  heats  flat  collecDon  plates  through  which  water  flows,  this  water  used  for  your  water  heater  

• Sun  converted  into  electrical  energy  through  solar  cells  

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Geothermal  Energy  

•  Thermal  energy  found  under  the  earth’s  surface  

•  Pump  water  underground  to  create  steam  which  in  turn  moves  the  generators  to  produce  electricity  

•  Does  not  pollute  but  not  found  everywhere  

• Biomass  Energy:    Energy  stored  in  living  things    

– Use  wood,  corn  stalks  (the  stuff  thrown  away),  and  convert  into  thermal  energy  

– Use  to  create  bio  fuel  -­‐    a  high-­‐  energy  alcohol  fuel    

Hydrogen  fuel  cell:  

•  generates  energy  by  reacDng  hydrogen  with  oxygen  – Waste  product  would  be  water  so  it’s  nonpolluDng    

Nuclear  Fusion:  

•  sDll  being  worked  on  today  but  would  probably  produce  li`le  polluDon  or  radioacDve  waste  

Wind  turbines:  •  converts  the  kineDc  energy  of  wind  into  rotaDonal  energy  of  the  turbines  which  is  then  converted  into  electrical  energy  by  an  electric  generator.  – Clean    and  wind  is  everywhere  but  takes  up  a  lot  of  space  

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Conserving  Energy  Resources  

•  Energy  resources  can  be  conserved  by  reducing  energy  needs  and  increasing  efficiency  of  energy  use  

•  Finding  ways  to  use  less  energy  or  to  use  energy  more  efficiently  is  known  as  energy  conservaDon  

•  Energy  Saving  Decisions  for  us  all:  turn  off  lights,  carpool,  change  the  light  bulbs,  bike  to  work  or  school,  etc.