ENERGY UNITS CALORIE (OLD UNIT) JOULE (J) (INTERNATIONAL UNIT) 1 CAL = 4.184 J KILOJOULE (KJ) ONE CALORIE IS THE ENERGY NEEDED TO RAISE 1G OF WATER BY.

ENERGY UNITS

CALORIE (OLD UNIT)

JOULE (J) (INTERNATIONAL UNIT)

1 CAL = 4.184 J

KILOJOULE (KJ)

ONE CALORIE IS THE ENERGY NEEDED TO RAISE 1G OF WATER BY 1OC

BTUBRITISH THERMAL UNITS

• 1 BTU IS THE HEAT NECESSARY TO RAISE 1 POUND OF WATER BY 1O F

• 1 BTU = 251.9958 CAL

POWER

THE STANDARD METRIC UNIT OF POWER IS THE WATT. AS IS IMPLIED BY THE EQUATION FOR POWER, A UNIT OF POWER IS EQUIVALENT TO A UNIT OF WORK DIVIDED BY A UNIT OF TIME. THUS, A WATT IS EQUIVALENT TO A JOULE/SECOND. 

 horsepower is occasionally used to describe the power delivered by a machine. One horsepower is equivalent to approximately 750 Watts.1HP = 750 W

KILOWATT HOUR

• IS THE STANDARD UNIT OF ELECTRICITY CONSUMPTION

•1KWH = 3.6 X 106 J

YOUR HOUSEHOLD'S MONTHLY ELECTRIC BILL IS OFTEN EXPRESSED IN KILOWATT-HOURS. ONE KILOWATT-HOUR IS THE AMOUNT OF ENERGY DELIVERED BY THE FLOW OF 1

KILOWATT OF ELECTRICITY FOR ONE HOUR. USE CONVERSION FACTORS TO SHOW HOW MANY JOULES OF ENERGY YOU GET WHEN YOU BUY 1 KILOWATT-HOUR OF

ELECTRICITY.

FOR MORE INFORMATION VISIT

HTTP://WWW.PHYSICSCLASSROOM.COM/CLASS/ENERGY

TO COMPARE DIFFERENT FUELS, WE NEED TO CONVERT THE MEASUREMENTS TO THE

SAME UNITS.• BTU CONTENT OF COMMON ENERGY UNITS

• 1 BARREL (42 GALLONS) OF CRUDE OIL = 5,800,000 BTU

• 1 GALLON OF GASOLINE = 124,238 BTU (BASED ON U.S. CONSUMPTION, 2011)

• 1 GALLON OF DIESEL FUEL = 138,690 BTU

• 1 GALLON OF HEATING OIL = 138,690 BTU

• 1 BARREL OF RESIDUAL FUEL OIL = 6,287,000 BTU

• 1 CUBIC FOOT OF NATURAL GAS = 1,023 BTU (BASED ON U.S. CONSUMPTION, 2011)

• 1 GALLON OF PROPANE = 91,333 BTU

• 1 SHORT TON OF COAL = 19,858,000 BTU (BASED ON U.S. CONSUMPTION, 2011)

• 1 KILOWATTHOUR OF ELECTRICITY = 3,412 BTU

In the United States, the Btu, a measure of heat energy, is the most commonly used unit for comparing fuels. Because energy used in different countries comes from different places, the Btu content of fuels varies slightly from country to country.

YOU HAVE A NATURAL GAS FURNACE IN YOUR HOME THAT USED 81,300 CUBIC FEET OF

NATURAL GAS FOR HEATING LAST WINTER. YOUR NEIGHBOR HAS AN OIL FURNACE THAT

USED 584 GALLONS OF HEATING OIL LAST WINTER.

WHICH HOME USED MORE ENERGY?

Natural Gas: 81300 cubic feet x 1023 BTU per cubic foot = 83,169 900 BTU

Oil : 584 gallons x 138 690 BTU per gallon = 80, 994 486 BTU

YOU WORK FOR AN ELECTRIC POWER COMPANY. YOUR COMPANY’S POWER GENERATORS CAN RUN ON ONE OF TWO

FUELS: NATURAL GAS OR RESIDUAL FUEL OIL. YOUR JOB IS TO SWITCH FUELS WHEN THE COST OF THE FUEL YOU ARE

CURRENTLY USING BECOMES MORE EXPENSIVE THAN THE OTHER FUEL. THIS WILL KEEP COSTS DOWN FOR YOU AND YOUR ELECTRICITY CUSTOMERS. YOUR COMPANY’S GENERATORS ARE CURRENTLY USING RESIDUAL FUEL OIL, BUT IN 2010 FUEL OIL

PRICES WERE NEARLY DOUBLE NATURAL GAS PRICES. BASED ON THE FUEL COSTS BELOW, YOU NEED TO DECIDE IF IT IS TIME TO

SWITCH TO NATURAL GAS:

NATURAL GAS: $5.26 PER THOUSAND CUBIC FEET / 1.022 MIO BTU PER THOUSAND CUBIC FEET = $ 5.15 PER MIO BTU

RESIDUAL OIL: $ 56.35 PER BARREL / 6.085 MIO BTY PER BARREL = $ 9.26 PER MIO BTU

FOR MORE INFORMATION VISIT

HTTP://WWW.EIA.GOV/ENERGYEXPLAINED/INDEX.CFM?PAGE=ABOUT_HOME

CAFE STANDARDS

The Corporate Average Fuel Economy (CAFE) are regulations in the United States,first enacted by the U.S. Congress in 1975 in the wake of the Arab Oil Embargo.Its purpose is to improve average fuel economy of cars and light trucks.

Renewable energy

Description of process

Benefits Disadvantages to the environment

Hydroelectricity

Solar Power

biofuels

Hydrogen fuel cells

Wind turbines

Resources to complete table on slide 10.

http://www.internationalrivers.org/environmental-impacts-of-dams

http://wwf.panda.org/what_we_do/footprint/water/dams_initiative/problems/environmental/

http://www.pcffa.org/dams.htm

http://education.nationalgeographic.com/education/encyclopedia/hydroelectric-energy/?ar_a=1

http://energy.gov/eere/energybasics/energy-basics

http://www.learner.org/courses/envsci/unit/text.php?unit=10&secNum=7

http://newshour-tc.pbs.org/newshour/science/hydrogen/images/interactive.swf

BUILD A WIND TURBINE

• HTTP://WWW.RE-ENERGY.CA/DOCS/WIND-TURBINE-CP.PDF

CALORIMETRYDETERMINE THE SPECIFIC HEAT OF A METAL

WHEN A HEATED PIECE OF METAL IS DROPPED INTO WATER AT ROOM TEMPERATURE, THE HEAT FROM THE METAL WILL TRANSFER TO THE WATER AND RAISE THE TEMPERATURE OF THE WATER.

CALORIMETRY IS A WAY TO DETERMINE THE HEAT LOST AND GAINED BY A SYSTEM USING THE GENERAL EQUATION Q = MC∆T

WHERE Q IS THE HEAT LOST/GAINED

M = MASS

C = SPECIFIC HEAT CONSTANT

∆T = FINAL TEMPERATURE – INITIAL TEMPERATURE

CALCULATING SPECIFIC HEAT OF THE METAL

Q WATER = M WATER C WATER ∆TWATER

QMETAL = MMETAL CMETAL ∆TMETAL