_____ percent of the energy that heats the earth and all of our buildings comes directly from the sun?
The sun provides other indirect forms of renewable solar energy such as:
wind, falling/flowing water, and biomass.
______ sold in the marketplace makes up the remaining 1% of the energy we use, most from nonrenewable resources.
commercial energy
___% of commercial energy consumed in the world comes from nonrenewable energy sources (fossil fuels, nuclear energy, etc.).
About 50% of people in developing countries burn _____ of commercial energy consumed in the world comes from nonrenewable energy sources (fossil fuels, nuclear energy, etc.).o heat dwellings and cook.
wood and charcoal
2._____ energy is renewable as long as it is not harvested faster than it can be replenished.
Many people in developing countries face a _____shortage that is getting worse because of unsustainable harvesting of _____.
Premature deaths are also caused from ____ by burning wood indoors in open fires.
breathing particles emitted
People in the U.S. consume as much energy in a ___ as a person in the poorest countries consumes in a ____.
In 2004, the U.S. used ___ of the world’s commercial energy with only ___ of the population.
24%; 4.6%
India has ___ of the world’s population and consumes about _% of the world’s commercial energy.
16%; 3
It takes at least ___`years and huge investments to phase in new energy alternatives to where they provide __-___% of total energy use.
50; 10-20
What is net energy?
Net energy is the amount of high-quality usable energy available from a resource after subtracting the energy needed to make it available for use.
What is crude oil?
Crude oil is a thick, gooey liquid consisting of hundreds of combustible hydrocarbons mixed with small amounts of sulfur, oxygen, and nitrogen impurities.
What Three geological events led to the presence of oil?
a. Sediments buried organic material faster than it could decay.
b. Sea floors with these sediments were subjected to the right pressure and heat to convert organic material to oil.
c. Oil collected in porous limestone or sandstone and was capped by shale or silt to keep it from escaping.
____are oil distillation products that are used as raw materials in manufacturing pesticides, plastics, synthetic fibers, paints, medicines, and other products.
____ has the largest supply of oil reserves with 25%.
Saudi Arabia
The U.S. has only ___% of the world’s proven oil reserves and about one-fourth of that comes from offshore drilling and from Alaska’s North Slope.
Known and projected global reserves should last -years, and U.S. reserves for -years depending on how rapidly we use oil.
thick, sticky heavy oil with a high sulfur content.
____ ___consists mostly of methane with small amounts of heavier hydrocarbons and a small amount of hydrogen sulfide.
natural gas
1. The long-term outlook for ____ gas supplies is better than for conventional oil.
2. ____gas use should increase because it is fairly abundant and has lower pollution and CO2 rates/unit of energy compared to other fossil fuels.
___is a solid fossil fuel formed 300–400 million years ago. It is mostly carbon with small amounts of sulfur and trace amounts of mercury
coal releases____?
SO2 and trace amounts of mercury and radioactive materials.
a partially decayed plant matter in swamps and bogs; low heat content
peat (not a coal)
low heat content; low sulfter content; limited supplies in most areas
lignite (brown coal)
extensively used as a fuel bc of its high heat content and large supplies; normally has a high sulfur conent
bituminous coal (soft coal)
highly desirable fuel because of its high heat content and low sulfer content; supplies are limited in most areas
C. ___can be converted to synthetic natural gas (SNG) by coal gasification or in to liquid fuel by coal liquefaction.
what happens in a conventional nuclear reactor?
isotopes of uranium and plutonium undergo controlled nuclear fission, and the resulting heat is used to produce steam that spins turbines to generate electricity.
what do control rods do?
regulates the rate of fission and amount of power the reactor produces
what does a moderator do?
down neutrons) keeps the reaction going
what does a coolant do?
circulates through the core to remove heat to keep the components from melting and to produce steam for generating electricity.