ENERGY RESOURCES Flashcards
battery
a device that converts chemical energy to electrical energy
primary batteries
- non rechargeable
- they generate electricity through a chemical reaction that occurs between the electrodes, a reaction that is non reversable
secondary batteries
- rechargeable
- they generate electrical energy through a reversible chemical reaction. when connected to a power source, the reaction is reversed to store energy
fuel cell
a device that uses the chemical energy of hydrogen or other fuel to cleanly and efficiently produce electricity
alternating currents
- electric charge that periodically reverses directions in a circuit
- well suited for long distance power transmissions because it can be easily transformed to different voltages
direct current
- electric charge that flows in a single-direction circuit
- voltage remains constant and does not change direction (does not require transformers)
AC/DC
AC is used to transport energy since it can travel long distances, then it is transformed to DC for regular use as it makes the voltage safer
fossil fuels
non renewable substances that have been formed over millions of years form the remains of dead organisms
coal
- mined and then put in a boulder to produce heat
- the heat is used to warm up water and create steam which causes a generator that is connected to a magnet to spin
- the movement of the magnet changes its polarity and produces electricity
oil
- extracted
- goes through a distillation process where the boiling point produces a different substance that produces energy
biomass
- organic matter derived from, a living, or recently living organism
- it is burned to create heat or processed into biofuel
geothermal
- harnessed from the earths internal heat
- wells are drilled to reach the reservoirs (areas of high temperature water)
- the hot steam is brought to the surface, which turns a turbine to generate electricity
wind
the wind turns blades of a turbine which moves a generator to produce electricity
tidal
the movement of waves underwater turns turbines which are connected to a generator to create energy
solar
- the panels absorb sunlight
- photons transfer energy to the atoms of silicone
- this makes electrons escape creating a current of energy
hydroelectric
- involves building a dam
- when the water is released it flows through a turbine that drives a generator to create electricity
nuclear energy
- relies on the controlled nuclear fission of U235
- control rods absorb neutrons that can be raised or lowered to control the rate of reaction
- the energy is passed through pipes to turn water into steam to move a turbine
how a battery works
- a cathode (+) and an anode (-) are immersed in an electrolyte solution
- the anode undergoes oxidation (losing electrons) and the cathode gains electrons
- the electrolyte facilitates the movement of electrons
- the greater the reactivity difference between two metals, the higher the voltage produced by the battery (more reactive metal has a greater tendency to release electrons)
implications of primary batteries
- they are made with lead which has potential health impacts
- 85% of the worlds lead consumption is for batteries
- 99% recyclable
- lead exposure takes place in mining and recycling process
implications of secondary batteries
- only 5% is recycled
- lithium isn’t a polluter, but it also includes metals that do have to be mined
coal pros
- abundant source
- reliable and stable
- cost effective
coal cons
- non renewable source
- environmental impact (climate change)
- health risks (inhalation of micro particles may cause diseases)
oil pros
- high energy density
- readily available
- infrastructure already in place
oil cons
- environmental impact (oils pills ghg emissions)
- finite resource
- price volatility
biomass pros
- clean and renewable
- since it is derived from plants, the production can offset carbon emissions
- good for storing energy
biomass cons
- can become non renewable
- can cause arable land
pros geothermal
- renewable and sustainable
- low ghg emissions
- reliable power
cons geothermal
- location specific
- high installation cost
wind pros
- clean and renewable
- low operating cost
- efficient use of space
wind cons
- intermittent
- noise and visual pollution
- remote
tidal pros
- renewable and sustainable
- high energy density
- low ghg emissions
tidal cons
. high initial cost
- intermittent
- site specific
solar pros
- renewable and sustainable
- reduces electricity costs
- environment friendsly
solar cons
- high initial cost
- intermittent energy
- site specific
hydroelectric pros
- renewable and reliable
- low ghg emissions
hydroelectric cons
- environmental impact
- site specific
nuclear energy pros
- los ghg emissions
- reliable and consistent
- high energy output
nuclear energy cons
- radioactive waste
- safety risks
