Energy Resources Flashcards

Flashcards xx

Three main greenhouse gases

Carbon dioxide, methane and water vapour.

Mechanism of the greenhouse effect

Short-wavelength solar radiation is absorbed by Earth’s surface and re-radiated as longer-wavelength infrared radiation, which is absorbed by greenhouse gases and heats the atmosphere.

Consequence of an enhanced greenhouse effect

Global warming, meaning an increase in the overall temperature of the planet.

Three consequences of global warming

Melting polar ice caps/glaciers, rising sea levels and coastal flooding, and disrupted climate/weather patterns.

Production of acid rain from fossil fuels

Burning fossil fuels releases sulfur dioxide ($SO_2$), which reacts with water and oxygen to form sulfuric acid.

pH level of acid rain

Below $\text{pH } 5$.

Fossil fuels

Fuels formed from the remains of dead plants and animals compressed underground under high pressure over millions of years.

Three main fossil fuels

Coal, oil and natural gas.

Why fossil fuels are ultimately dependent on the Sun

They originally came from plants that gained energy from sunlight through photosynthesis.

Major advantage of fossil fuels

They are reliable — if fuel is available, electricity can be generated when needed.

Three disadvantages of fossil fuels

They will run out, they release $SO_2$ causing acid rain, and they release $CO_2$ contributing to global warming.

Energy-transfer sequence in a fossil-fuel power station

Chemical energy → heat energy → kinetic energy → electrical energy.

Reason fossil-fuel power stations are relatively inefficient

A large amount of energy is wasted as heat to the surroundings; efficiency is about $30\%$.

Advantages and disadvantages of solar energy

Advantages: low running costs and no $CO_2$ during operation. Disadvantages: expensive to install and can cause visual pollution.

Advantages and disadvantages of wind energy

Advantages: low running costs and no $CO_2$ during operation. Disadvantages: unreliable and can be hazardous to birds.

Advantages and disadvantages of wave energy

Advantages: low running costs and no $CO_2$ during operation. Disadvantages: unreliable and can be hazardous to shipping.

Advantages and disadvantages of hydroelectric power

Advantages: quick response to changes in electricity demand and no $CO_2$ during operation. Disadvantage: dams can destroy habitats.

Advantages and disadvantages of biomass/wood

Advantage: it is reliable. Disadvantages: it produces $CO_2$ when burned and requires large areas of land.

Advantages and disadvantages of tidal energy

Advantages: low running costs and no $CO_2$ during operation. Disadvantage: it can cause navigation problems for ships.

Advantages and disadvantages of geothermal energy

Advantages: reliable and no $CO_2$ during operation. Disadvantage: it is only viable in certain locations.

Renewable resources that depend on the Sun

Solar, wind, wave, hydroelectric and biomass.

Renewable resources that do NOT depend on the Sun

Tidal and geothermal.

Nuclear fission

The splitting of a uranium nucleus into smaller nuclei, releasing a large amount of energy as heat.

Why nuclear fission is a non-renewable energy resource

It uses uranium ore, which is mined from the ground and will eventually run out.

Four advantages of nuclear fission power

It is reliable, creates jobs, reduces $CO_2$ emissions during operation and is very energy dense, so a small amount of fuel releases lots of energy.

Three disadvantages of nuclear fission power

It produces dangerously radioactive waste, there is a risk of a major accident, and local people may oppose nuclear stations because of fear (NIMBY).

Nuclear fusion

The joining of deuterium and tritium hydrogen nuclei to form a larger nucleus, releasing a large amount of energy.

Decommissioning a nuclear fission power station

Shutting the station down and restoring the site. It is expensive because radioactive waste and components require specialist equipment and specially trained workers.

Non-renewable energy resources

Energy resources that are used up faster than they can be replaced and will eventually run out.

Renewable energy resources

Energy resources that can be replenished naturally at a rate equal to or faster than they are consumed, so they will not run out.