Renewable Energy Sources
By 2023, Australia hit 39% renewable electricity, but AEMO says we need 82% by 2030. What's the barrier?
Printable Worksheets
Print or save as PDF, or build a custom worksheet from any module's questions.
Q1 · Australia has one of the best solar resources in the world, yet solar still produces a minority of our electricity. Before reading, what do you think are the biggest obstacles stopping us from running on 100% solar?
Q2 · What makes an energy source "renewable"? Can you think of any energy sources that seem renewable but might have hidden limits?
● Know
- The main renewable energy sources: solar, wind, hydro, bioenergy, geothermal
- That renewable sources are naturally replenished
- Australia's current energy mix and renewable targets
● Understand
- How each renewable technology converts energy into electricity
- Why different regions suit different renewables
- The advantages and limitations of each source
● Can do
- Describe energy transformations in renewable systems
- Compare renewable and non-renewable sources
- Evaluate energy choices for different Australian locations
🇦🇺 Australia's Electricity Mix (2024)
On a windy afternoon in South Australia, you can watch wind turbines spinning fast enough to supply more than 100% of the state's electricity demand, the surplus exported to Victoria. On a still, cloudy night those same turbines stand motionless. This contrast captures the central challenge of renewable energy. Renewable energy comes from sources that are naturally replenished: sunlight, wind, flowing water, geothermal heat and biomass; unlike fossil fuels, these sources will not run out on human timescales. However, each renewable source has its own strengths, weaknesses and ideal locations.
Australia is exceptionally well placed for solar and wind energy. We receive more solar radiation per square metre than any other continent. Our southern coasts have strong, consistent winds. Hydroelectric power is already well developed in the Snowy Mountains. Geothermal energy shows promise in regions like the Cooper Basin where hot rocks lie close to the surface.
South Australia now regularly generates over 60% of its electricity from wind and solar. On particularly windy days, renewable output exceeds 100% of demand and the surplus is exported to Victoria or stored in batteries.
What to write in your book
- Renewable energy comes from naturally replenished sources
- Australia is ideal for solar and wind power
- Each renewable source has different strengths and ideal locations
Match each renewable source to its key strength.
The main challenge with solar and wind is intermittency. The Sun only shines during the day; the wind does not always blow. This does not mean renewables are inadequate, it means we need storage and grid management to balance supply and demand. Batteries, pumped hydro and smart grids are the keys to a high-renewable future.
Cost is no longer the main barrier. Solar panels and wind turbines are now the cheapest sources of new electricity in most of the world. The remaining challenges are technical: storing energy for hours or days, managing grid stability, and building transmission lines from renewable-rich regions to cities.
The Tesla Megapack battery at Hornsdale in South Australia responds to grid fluctuations in milliseconds, far faster than any gas turbine. It has saved consumers millions of dollars by stabilising prices during peak demand.
AEMO publishes integrated system plans showing how Australia's grid could reach over 80% renewables by 2030. The plan involves building new transmission lines, adding storage, and retiring coal plants as renewable capacity grows.
What to write in your book
- Solar and wind are intermittent, they depend on weather
- Storage and grid management solve intermittency
- Renewables are now the cheapest new electricity in most places
Decisions about energy are not purely scientific, they involve economics, politics and ethics. However, science provides the evidence base. When evaluating claims about energy policy, distinguish between facts, predictions and values. A fact might be that solar radiation is abundant. A prediction might be that batteries will become cheaper. A value might be that we should prioritise jobs in one sector over another.
Good scientific literacy means being able to identify which statements provide evidence for a claim and which are merely tangentially true. Just because a statement is factual does not mean it supports the claim being made.
Claiming Australia should invest in renewables because coal mining started in 1791 is illogical, the historical date has no bearing on future policy. Claiming it because solar radiation is abundant and storage is cheapening provides relevant scientific and economic evidence.
What to write in your book
- Evaluate claims using relevant scientific evidence
- Distinguish facts, predictions and values in policy debates
- A true statement does not always support the claim being made
Click each sentence that supports the claim.
Renewable sources are defined by their replenishment rate. Sunlight arrives continuously from nuclear fusion in the Sun. Wind is driven by solar heating of the atmosphere. Hydrological cycles are powered by evaporation and precipitation. Geothermal energy taps heat from radioactive decay in Earth's core. These processes operate on timescales of millions to billions of years.
By contrast, fossil fuels are non-renewable because they form over millions of years from buried organic matter, and we are consuming them thousands of times faster than they form. Once a coal seam or oil reservoir is depleted, it is gone on any human-relevant timescale.
At current rates of consumption, known global coal reserves might last around 130 years. But burning them all would release enough carbon dioxide to cause catastrophic climate change. Renewable energy offers a path to sustain both our civilisation and our climate.
The CSIRO and Australian National University are world leaders in perovskite solar cell research. These next-generation cells could be cheaper, lighter and more efficient than silicon, potentially making solar the dominant global energy source this century.
What to write in your book
- Renewable sources are replenished naturally on human timescales
- Fossil fuels are non-renewable, they form millions of times slower than we use them
- The Sun, wind and water cycles will outlast human civilisation
🎮 Design an energy mix for a regional Australian town
Copy Into Your Books
▼Solar Power
- Light → Electrical (+ thermal waste)
- Silicon cells knock electrons loose
- ~20% efficient
- Australia: highest rooftop uptake globally
Wind Power
- Kinetic (wind) → Kinetic (blades) → Electrical
- ~45% efficient
- Larger = more efficient
- SA: 60%+ from wind
Hydroelectric
- GPE → Kinetic → Electrical
- ~90% efficient (most efficient!)
- Pumped hydro = energy storage
- Snowy 2.0 = largest in southern hemisphere
Other Sources
- Bioenergy: chemical → thermal → electrical
- Geothermal: thermal → kinetic → electrical
- All renewables: naturally replenished
- Challenge: intermittency needs storage
Energy Transformation Chains
1 Rooftop solar panel on a house in Brisbane.
2 Wind turbine at the Hornsdale Wind Farm, South Australia.
3 Hydroelectric turbine at the Snowy Mountains Scheme.
Design a Renewable Town
At the start of this lesson you were asked: Australia receives more solar radiation than almost any country on Earth, enough to power the nation many times over, yet we still get most electricity from coal. What is actually stopping us from switching to fully renewable energy?
Now that you've explored the strengths and limitations of each renewable technology, what do you think the real barriers are? Has your answer changed?
Short Answer Questions
Use clear scientific language. Check the model answers after attempting each question.
Question 1. Explain why pumped-hydro energy storage is described as a "giant battery." In your answer, describe the energy transformations that occur when the system is charging (pumping water uphill) and when it is discharging (generating electricity).
Question 2. A student claims that because Australia has "unlimited sunshine," solar power alone can meet all of Australia's electricity needs. Evaluate this claim, providing at least one argument supporting the claim and at least two arguments challenging it. Use specific scientific evidence from this lesson.
Question 3. South Australia's electricity grid currently operates with over 60% wind power. Some critics argue that this level of wind power makes the grid unreliable. Using evidence from this lesson, explain how South Australia has addressed the reliability challenge, and evaluate whether other Australian states could adopt a similar approach. Your answer should refer to energy transformations, storage technologies, and geographical factors.
Model answers (click to reveal)
Model Answers
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