Energy Resources (AQA GCSE Combined Science: Synergy: Physical Sciences): Revision Note
Exam code: 8465
Written by: Leander Oates
Updated on
Non-renewable resources
A non-renewable energy resource is used up faster than it can be replenished and will eventually run out
Non-renewable resources include:
Coal (fossil fuel)
Crude oil (fossil fuel)
Natural gas (fossil fuel)
Nuclear fuel
How non-renewable resources are used
Electricity generation:
Fossil fuels are burned to produce steam, which turns turbines connected to generators
Nuclear fuel undergoes fission to produce heat and steam, which also turns turbines
Currently, the majority (around 84%) of the world's energy is still produced from non-renewable sources
Transport:
Petroleum products from crude oil power the majority of road, air and sea vehicles
These products include:
Petrol
Diesel
Kerosene
Heating:
Natural gas is the most widely used fuel for central heating systems
Energy resources overview
Energy resources | Description |
|---|---|
Fossil fuels | Fossil fuels are combusted to heat water to produce steam to turn turbines to generate electricity |
Nuclear | Nuclear fuels undergo fission to heat water to produce steam to turn turbines to generate electricity |
Bio-fuels | Plant matter, ethanol or methane can be produced and used as a fuel in place of fossil fuels |
Wind | Wind turns turbines directly to generate electricity |
Hydroelectric | Water is stored at a height, and when released, rushing water turns turbines directly to generate electricity |
Tidal | The movement of water due to tides turns turbines directly to generate electricity |
Solar | Solar cells use light to generate electricity, solar panels use thermal radiation to heat water to produce warm water for household use |
Examiner Tips and Tricks
When evaluating non-renewable resources in terms of environmental impact:
Burning fossil fuels releases CO2, which contributes to global warming
Burning fossil fuels also releases SO2, which causes acid rain
Burning fossil fuels releases particulates, which affect health and contribute to global dimming
Nuclear power produces radioactive waste that remains radioactive for a very long time and must be safely buried
Non-renewable resources have a reliability advantage: they can generate electricity on demand, regardless of weather conditions.
Renewable resources
A renewable energy resource is one that is being (or can be) replenished as it is used — it will not run out
Renewable resources include:
Plants that provide biofuel (plant matter, ethanol or methane used as fuel)
Wind turbines - wind turns turbines directly to generate electricity
Solar panels - produce electricity or heat water
Hydroelectricity - water stored at height rushes down to turn turbines
Tidal barrages or undersea turbines - movement of tidal water turns turbines
How renewable resources are used
Electricity generation:
Wind, hydroelectric, tidal and solar all generate electricity without burning fuel
Transport:
Biofuel can be used in place of petroleum products
However, the claim that biofuels are carbon-neutral is controversial
A growing number of vehicles run on electricity
These produce zero emissions while being driven
Although the electricity used for charging may still come partly from non-renewable sources
Heating:
Solar panels heat water directly for household use
Evaluating renewable resources
Environmental advantages:
No CO2 emissions
Less global warming
No SO2 emissions
Less / no acid rain
No particulates
Less impact on health
Less global dimming
Renewable and sustainable
Finite fossil fuel supplies are conserved
Environmental disadvantages:
Wind turbines:
Noise pollution
Visual pollution
Bird kill
Hydroelectric:
Habitat disruption from flooding valleys to create reservoirs
Solar and wind:
Large land area required
Reliability:
Wind and solar depend on weather conditions
It is not always windy or sunny, meaning fossil fuel power stations must be kept available as backup
Tidal is more predictable as tides follow regular patterns
Hydroelectric reliability depends on rainfall
Examiner Tips and Tricks
If a question asks specifically about environmental advantages or disadvantages of an energy resource, do not refer to cost. Examiners are often told to ignore references to cost in environmental questions. Keep evaluation focused on emissions, waste, habitat and reliability.
To access full marks in an evaluation question, always link cause to consequence:
"No CO₂ is emitted, so there is less global warming" (not just "it doesn't release CO₂")
"Wind turbines are not always generating because it is not always windy, so fossil fuel power stations must be used as backup"
Unlock more, it's free!
Join the 100,000+ Students that ❤️ Save My Exams
the (exam) results speak for themselves:
Was this revision note helpful?