8 Energy Production Flashcards
Specific Energy (ES) vs Energy Density (ED)
ES = energy per unit mass of a fuel;
ED = energy per unit volume of a fuel
primary energy source
energy source found in the natural environment
secondary energy source
energy that results from the transformations of the primary resources
renewable energy source
replenishes faster than being consumed; doesn’t run out
describe how nuclear power stations work
nuclear fission releases neutrons with high KE → internal energy → water to steam → turns a turbine connected to a generator
describe how hydroelectric power stations work
Falling water releases GPE → KE → turns a turbine connected to a generator → generates electricity
what are the advantages and disadvantages of solar energy?
renewable, unlimited supply, no greenhouse gas; weather-dependent, inefficient, high set-up cost
how do you calculate the density of a fuel?
energy density/specific energy
examples of primary energy source
oil
coal
kerosene
examples of secondary energy source
petrol (from refining oil)
heat (from burning coal)
examples of renewable energy source
solar, wind, hydroelectric, tidal, geothermal
describe how fossil fuel power stations work
burn fossil fuel → heat water → steam → turns a turbine connected to coils of wire in electricity generators → electromagnetic induction produces electrical energy
what are the advantages and disadvantages of fossil fuel power?
abundant supply, reliable and available energy at any time; greenhouse gas produced, non-renewable
what are the advantages and disadvantages of nuclear power?
abundant supply, no greenhouse gas, large amount of energy produced; radioactive waste is dangerous and expensive to deal with
when is the equation P = (1/2)Aρv3 used and what are the assumptions?
for wind generators
assumes:
- the turbine and generator are 100% efficient
- the wind is moving perpendicularly to the plane of the blades
- the air which strikes the blades will lose all of its kinetic energy
