20% of the population uses how much of the world's energy each year.
1/2
Energy use in the U.S. today is the result of
Inputs and outputs of a system
the best form of energy to use depends on the
particular purpose for what's needed
nearly 30 % of energy in the U.S. is used for
transportation
derived from biological material that became fossilized millions of years ago
fossil fuels
People that live in urban areas most likely use this type of energy
fossil fuel
The United States energy consumption is 9 % of this energy
nuclear fuel
this refers to both the efficiency of the process we use to obtain the fuel and efficiency of the process that converts the fuel
energy efficiency
these are the 2 most energy-efficient modes of transportation
trains and motocycles
an energy source with a finite supply, primarily fossil fuels and nuclear fuels
nonrenewable energy resource
It's an energy source that is bought and sold
Commerical energy sources
32 % of the energy used by the United States is for
Industrial use
If coal's energy efficiency is 35 % then how much is lost
about 2/3, 65%
People in the developed world tend to choose SUV's, minivans, and picking trucks because of
comfort, style, and conveniece
fuel derived from radioactive materials that give off enrgy
nuclear fuel
It's an energy source gathered by individuals for their own immediate needs
Subsistence energy source
Energy use varies due to these 2 factors
regionally and seasonally
This is the amount of energy we get from an energy source for every unit of energy is expended on its production
EROEI
Hybrid electric vehicles account for only what percent of total car sales
3%
aerobically the dead biomass is broken down by decomposer which reenter the food web
fast
The change in energy demand reflects this
the level of industrialization
Highly populated areas tend to use less, what type of energy
coal
To find the EROEI you have to divide by these two values.
Energy obtained from the fuel % Energy invested to obtain the fuel
Energy efficiency is an important consideration when making fuel and technology choice but what is also another important
fuel choice
anaerobically large amounts of detritus build which form
nonrenewable energy resource