7.4: Energy storage and conservation

hydrogen gas

combines hydrogen and oxygen gas to produce water and electricity

liquid hydrogen is ________

combustible

what is the big benefit of hydrogen gas?

emits no CO2

what is the major problem with hydrogen gas

negative net energy yield, making it more of an “energy storage” molecule

________ are the best way available to produce electricity and it is expensive/ cheap to produce

fuel cells

expensive

what is the key to determining if hydrogen gas is polluting or not

how it is produced- fossil fuels or renewable energy used

hydrogen energy 3 advantages

hydrogen energy 3 disadvantages

low environmental impact, good oil substitute, safer than gasoline and natural gas

energy needed to produce fuel, high cost, take time to phase in

key energy resource questions (6)

how much available for future and longterm

net energy yield

cost to develop, phase in, and use the resource

dependence on resource affecting national/global economic and military security

vulnerability to terrorism and natural disasters

environmental and health risks?

what two things will help determine energy producing paths

energy resource questions

political and economic pressure

choosing energy paths

made not with short-sighted economic goals, but long term economic and environmental goals

choosing energy paths-supply side

fossil fuels and nuclear power interests

look for non-renewable energy resources and build more non-renewable power plants

choosing energy paths- demand side

environmental interests

reduce waste, expand renewable energy resources

energy analyst conclusions

shift to decentralized, renewable systems because they are less prone to disruptions

shift to renewable resources would result in (6)

decentralized and efficient more protected energy economy

better nations security with less dependence to middle east

reduce trade deficits w countries that export oil to us

reduce greenhouse gas and pollution emission

create jobs

save money for consumers

what keeps renewable energy from being more widely used?

subsidies, tax breaks, and rebates for renewable energy are much lower than non-renewable energy sources

cost of non-renewable resources don’t include their “real costs”

3 solutions to make transition to sustainable energy

improve energy efficiency

reward utilities for reduced demand for electricity

provide large tax credits for buying efficient cars, houses, and appliances

3 solutions to get more renewable energy

increase use of renewable energy

provide subsidies and tax credits for using renewable energy

encourage government purchase of renewable energy devices

3 solutions to reduce pollution and health risk

cut coal use 50% by 2020

phase out coal subsidies

phase out nuclear power subsidies, tax breaks, and loan guarantees

energy efficiency as an energy “resource”

reduce waste of energy

improve energy efficiency

energy efficiency

measure of how much work we get from each unit of energy we use

____ of all commercial energy in the US is wasted. ____ from _____________, and ___ is _____________

84%

41%, 2nd law of thermodynamics

43%, wasted

3 solutions from reducing energy waste

prolongs fossil fuel supplies

reduces oil imports and improves energy security

high net energy yield

what is the cheapest, cleanest, and quickest way to provide more energy?

economic and environmental advantages? (3)

reducing energy waste

best for reducing pollution and environmental degradation

best for slowing climate change and global warming

best for economic and national security

___________ average 3x less efficiency than US

___________ average 3x more efficient than US

developing countries

developed countries

4 devices wasting large amounts of energy. how much wasted with each?

incandescent light bulbs- 90-95%

motor vehicles with internal combustion engine- 94%

nuclear power plants-80-90%

coal fired power plants-66%

net energy yield for nuclear power transportation

nuclear power transported then converted to heat, each step wasting energy

passive solar store heat with slow release

one step process allows for 90% net yield

industry accounts for ___ of energy consumption in the world, ____ in the US. what are the largest users?

30%

40%

production of metals, chemicals, cement, and paper, petrochemicals for fertilizers, plastics, detergents