Physics - P3: Energy resources and Energy demands

Renewable resource

A resource that can be replenished as quickly as it is used

Non-renewable resource

A resource that can't be replenished as quickly as it is used

Carbon neutral

When the amount of CO2 released is the same as the CO2 absorbed (by plants)

Solar energy

How it works:

-Protons from sunlight collide with semiconductors (on solar panels). Each panel has a negative and positive layer making an electric field, so they work similar to a battery

Transfers taking place:

-Light energy to electric energy

Advantages:

-No emissions

-Quiet

Disadvantages:

-Doesn't produce a lot of electricity

-Only works during the day

Wind power

How it works:

-The shape of the turbine's blades cause air pressure to be uneven, so they spin around. The blades are attached to a rotor shaft, which spins gears and increases rotation so it can generate electricity

Transfers taking place:

Kinetic energy to electrical energy

Advantages:

-Can be on land or sea

-Can provide a lot of electricity

Disadvantages:

-Takes up a lot of space

-Only works when there is a lot of wind

Hydopower

How it works:

-Water movement is converted to energy. One way to do this is by storing water in a reservoir and then releasing it through a turbine

Transfers taking place:

-Kinetic energy to electrical energy

Advantages:

-Can recycle water

-Affordable

Disadvantages:

-Could disrupt wildlife

Biofuels

How it works:

-Biomass solids are broken down into biofuels by using enzymes, yeast or extreme heat

Transfers taking place:

-Chemical energy to thermal energy

Advantages:

-Reduces waste products from animals being wasted

-Renewable

Disadvantages:

-Might release greenhouse gases when burned

Geothermal heat pumps

How it works:

-A loop of pipes are buried underground and filled with water, The water then circulates and absorbs heat from the Earth. It is then brought to a heat pump and to the home. It releases energy and does the opposite in the summer

Transfers taking place:

-Geothermal energy to Thermal energy

Advantages:

-Doesn't cost a lot

-Works well during all seasons

Disadvantages:

-May not work well everywhere

Tidal power

How it works:

-Usually uses tidal motions to spin a turbine connected to a generator; A form of hydropower

Transfers taking place:

-Kinetic energy to Electrical energy

Advantages:

-Predictable

-East to install

Disadvantages:

-Consumption patterns might not match tidal patterns

-Doesn't generate a lot of power

Solar thermal

How it works:

-Passive systems: Enhance ability to capture sun-rays (e.g. greenhouses)

-Active systems: Mechanical components circulate heat (e.g: mirrors)

Transfers taking place:

-Solar energy to thermal energy

Advantages:

-Renewable

-Low maintenance

Disadvantages:

-Doesn't produce a lot of energy

-Usually in deserts

Geothermal energy

How it works:

-Heat from the Earth's crust warms the water in underground reservoirs and the hot water breaks through the surface as steam/water. A common way to change this to electricity is to pass the steam through a turbine

Transfers taking place:

-Thermal energy to electrical energy

Advantages:

-Low CO2 emissions

-Minimal environmental impact

Disadvantages:

-Takes up a lot of space

-Expensive

Gas power stations

Advantages:

-Doesn't cause acid rain

-Less CO2 and soot released

Disadvantages:

-More difficult to obtain

-Needs refining

Coal power stations

Advantages:

-Easy to obtain

Disadvantages:

-Releases Sulfur dioxide (causes acid rain)

-More CO2 and soot is released