Chapter 6 - Energy Generation

What are the two main categories of energy generation?

Fossil fuels and renewables.

What is the fundamental process used in most forms of electricity production to turn a generator?

Rotating a turbine.

In power stations using fossil fuels or biofuels, what substance is superheated to create steam for turning turbines?

Water

How do wind, wave, and hydroelectric systems differ from fossil fuel plants in how they rotate a turbine?

They convert kinetic energy directly into mechanical energy to rotate the turbine, without using steam.

What type of energy conversion does a generator perform?

It converts mechanical energy from a turbine into electrical energy.

Fossil fuels are considered a _____ resource because they were formed over millions of years and cannot be replaced.

finite

Name three examples of fossil fuels.

Coal, oil and natural gas.

What greenhouse gas is produced when fossil fuels are burned?

Carbon dioxide (CO₂)

Why are countries trying to reduce their dependency on fossil fuels?

To reduce the build-up of greenhouse gases, which contribute to global warming.

What is the primary reason it is difficult to reduce dependency on fossil fuels?

They are generally more cost-effective than renewable energy sources.

How is coal typically prepared before being burned in a power station?

It is crushed into a fine powder.

What is one major advantage of using coal for energy generation regarding its availability?

There is enough coal on Earth to last for hundreds of years.

What significant environmental damage is associated with the extraction of coal?

Damage is caused to natural land during the mining process.

What is fracking?

The process of extracting natural gas trapped in shale rock by cracking it with high-pressure liquid.

What are the three main components of the high-pressure mixture used in fracking?

Water, sand and chemicals.

What are two environmental concerns related to the fracking process?

Potential pollution of the water table or causing earth tremors.

Compared to coal and oil, what is an advantage of natural gas regarding emissions?

It emits less carbon dioxide when burned.

What is a significant safety risk associated with natural gas?

It is highly flammable, and leaks can cause explosions.

Besides electricity generation, what is a primary use for oil in the UK?

It is mainly used for fuel or is turned into plastics.

What is a major disadvantage of burning oil for energy concerning air quality?

It creates significant air pollution.

What is scrubbing?

The technology used to remove pollutants like sulphur from the emissions of coal-fired power stations.

What mixture is sprayed into emissions during the 'scrubbing' process to absorb sulphur?

A mixture of powdered limestone and water.

Renewable energy sources are considered _____ resources because they harness the Earth's natural resources that will not run out.

non-finite

List five examples of renewable energy sources.

Wind, solar, tidal, hydroelectric and biomass.

Why is nuclear power sometimes included in the renewable category, despite not being traditionally renewable?

A small amount of fuel produces a significant amount of energy, and it produces very low levels of CO₂.

How do wind turbines generate electricity?

The wind turns the propeller blades, which drives a generator to produce electricity.

What is a key advantage of wind power during colder months?

It tends to have a higher output in winter when energy demand is higher.

What is a major drawback of wind turbines related to their operational consistency?

They only produce power when it is windy, and not when it is too windy.

What is the term for the public sentiment of supporting renewable energy in principle, but objecting to developments like wind farms being located nearby?

NIMBY (Not In My Back Yard)

What is the name for the cells that convert light energy into electrical current in solar panels?

Photovoltaic (PV) cells

What is the scientific principle behind how solar panels work?

The photovoltaic effect, where light photons allow electrons to flow, creating an electric current.

What is a primary disadvantage of solar energy related to time of day?

No power is generated at night.

How does the efficiency of solar panels change with the seasons?

Production is lower in winter months due to shorter days and a reduced angle of the sun's rays.

How is electricity generated from tidal energy?

The rise and fall of the tide forces water through turbines, which drive generators.

What is a tidal barrage?

A dam-like structure built across the mouth of a river to harness tidal forces for energy generation.

What is a key advantage of tidal energy over wind and solar power?

It is more predictable and generally more consistent.

What is a major challenge associated with the machinery for tidal power?

It is located in harsh environments, making repair and maintenance difficult.

What does HEP stand for in the context of energy generation?

Hydroelectric Power