Exam 3-Chapter 14

Question 1

what are primary energy sources

Answer 1

used in the form found in nature (sun, geothermal, coal, wood, nuclear)

Question 2

how are fossil fuels made

Answer 2

were formed 100 to 500 million years ago in swamps and shallow seas where anaerobic conditions slowed down decomposition/pressure and heat converted vegetation to fossil fuels (natural gas deeper down).

Question 3

what are the major sources of energy on Earth

Answer 3

Solar, fossil fuels, hydroelectric, biomass

Question 4

oil sands/shale-how do they affect the EROI

Answer 4

it costs more because oil sands are very dirty and need to be refined much more. sand and contaminants like bitumen needs to be separated (dirty and tar-like material/needs to be melted away). destroyed forests and wetlands/huge greenhouse gas generation. Shale and oil sands very low EROI 2.9:1 (vs coal 80:1)

Question 5

Oil (2 of 3 fossil fuels) about

Answer 5

crude oil extracted from the ground/dark mixture of hydrocarbons, sulfur, nitrogen and is refined to remove contaminants. now a major energy source for the world (except eastern europe and asia), cleaner than coal and has improved air quality

Question 6

natural gas (3 of 3 fossil fuels) about

Answer 6

found with or below oil, is mostly methane, burns cleaner than coal or oil, pipelines transport, used in heating, cooking, industry.

Question 7

environmental impacts of fossil fuel extraction

Answer 7

oil spills, rising greenhouse gases, air, water and land pollution, loss of biodiversity, damage to fragile ecosystems

Question 8

what energy sources are nonrenewable

Answer 8

fossil fuels (coal, oil, natural gas) - they take millions of years to form, and nuclear energy (clean but not renewable)

Question 9

what are secondary energy sources

Answer 9

made from primary energy. Electricity (energy holding systems)

Question 10

what does EROI tell you about an energy source

Answer 10

energy returned on energy invested - It determines the price of energy. If sources of energy can be obtained easily and cheaply, it will allow the price to remain low

Question 11

Coal (1 of 3 fossil fuels) about

Answer 11

most abundant, obtained by mining or mountain top stripping, dirtiest form of energy, worlds largest source of CO2, used for heating, cooking, and generating electricity.