Trends in energy use (Edexcel GCSE Physics Combined Science): Revision Notes

Trends in energy use

Energy Use Over Time:

The types of energy resources we use have changed over time due to advancements in technology, environmental concerns, and costs.

20th Century: As the global population increased, the demand for energy rose dramatically. Most of this energy came from fossil fuels (coal, oil, and gas) and nuclear power.

21st Century: In recent years, the demand for electricity in the UK has actually decreased. This is because of improvements in energy efficiency—we're using energy more wisely and wasting less.

Current Energy Sources:

• Non-renewable energy sources like coal, gas, and nuclear power still provide most of the UK's energy.
• However, there is a growing use of renewable energy sources like wind power, solar energy, and biofuels.

Uses of Energy Resources:

1. Fossil Fuels:

• Generate electricity in power plants.
• Fuel for cars (e.g., petrol and diesel).
• Gas for heating homes and cooking.

2. Biofuels (Renewable):

• Power vehicles, often as an alternative to petrol or diesel.
• Used in solar water heaters to provide hot water for homes.
• Used to heat homes in some systems.

The UK's Renewable Energy Goals:

The UK aims to produce 15% of its energy from renewable resources in the coming years. This push for renewables comes from:

• Growing awareness of the environmental impact of non-renewable energy sources.
• Pressure from the public and other countries to reduce carbon emissions and adopt cleaner energy.
• The rise of electric cars and hybrid vehicles, which reduce reliance on fossil fuels.

Challenges and Disadvantages of Renewable Energy:

1. Cost and Investment:

• While renewable energy is environmentally friendly, it's often more expensive to build new power plants that use renewable resources.
• Smaller energy providers may be reluctant to invest in renewable energy because fossil fuels are currently a cheaper way to meet energy demand.

2. Aesthetic and Public Opinion:

• Building new renewable energy plants (like wind farms) often faces opposition because many people find them visually unattractive.

3. Reliability Issues:

• Some renewable energy sources, like wind power, are unreliable because they depend on weather conditions. This makes it hard to guarantee a steady energy supply.
• To meet demand, a combination of renewable and non-renewable power plants is often needed, which is expensive.

4. Research Costs:

• Researching and developing reliable renewable energy technologies is costly, even with government funding. As a result, many energy providers continue to rely on non-renewable power stations.

5. Personal Costs:

• Switching to renewable energy on a personal level can be costly. For example, hybrid and electric cars are often more expensive than regular petrol or diesel cars, making the transition slower.