Energy resources — AQA A-Level Environmental Science

Energy resources examines the thermodynamic principles, technological extraction methods, and environmental trade-offs associated with non-renewable fuels, nuclear power, and renewable alternatives. It evaluates how human society harnesses primary energy and converts it into secondary energy carriers to sustain modern industrial systems.

Within AQA Environmental Science, this unit directly links to atmospheric pollution, climate change, and resource management. Mastering this topic requires applying quantitative metrics such as energy density and load factors to appraise viable energy mixes, national grid decarbonisation pathways, and energy conservation strategies.

• →Energy density (MJ/kg or MJ/m3) and power density (W/m2), which govern fuel transportability, infrastructure footprint, and material requirements.
• →Intermittency and dispatchability, distinguishing base-load generation, peak-shaving capacity, and the necessity of energy storage mechanisms.
• →Locational factors and geographic constraints, such as kinetic energy flux in wind or wave, solar insolence, and geomorphological head in hydro systems.
• →Secondary energy carriers and storage mechanisms, including hydrogen generation, pumped hydroelectricity, battery banks, and heat stores.
• →Whole life-cycle analysis (LCA), measuring environmental costs from extraction, construction, and operational phases through to decommissioning.

• Analyses how a named energy resource supported a specific past development, such as coal powering industrialisation.
• Explains how access to affordable energy influenced economic growth and living standards over time.
• Evaluates a future supply problem, such as depletion of finite fossil fuels or dependence on imported fuel, with its consequences.
• Assesses the intermittency of renewable sources and the role of storage or backup in maintaining reliability.
• Weighs responses to future supply problems, comparing cost, security of supply and environmental impact.
• Reaches a supported judgement on which future energy strategies are most effective and why.

• 💡Use the command words: analyse past and future importance, then evaluate the impact of future supply problems.
• 💡Support each judgement with a named example, such as a fuel, country or technology, rather than general statements.
• 💡End with a clear conclusion that weighs the evidence and states which strategy is most justified.
• 💡Always state exact physical units when completing energy calculations (e.g. MWh, TJ, W/m2) and clearly show intermediate steps to protect method marks.
• 💡Structure 9-mark comparative essays around clear evaluative criteria: thermodynamic efficiency, locational availability, environmental degradation, and economic capital intensity.
• 💡Quote named case studies or specific technologies (e.g. multi-junction photovoltaic cells, CCGT with amine scrubbing, run-of-the-river vs barrage systems) rather than speaking generally.

• Describes energy history without analysing its importance to development; correct this by linking each resource to a specific social or economic change.
• Lists future problems without evaluating their severity or possible responses; correct this by weighing impacts and comparing solutions.
• Treats one energy source as a complete solution; correct this by assessing trade-offs in cost, reliability and environmental effect.
• Assuming nuclear energy directly produces greenhouse gas emissions during generation; operational fission emits no carbon dioxide, although life-cycle emissions exist from mining and enrichment.
• Believing that an electricity grid can transition completely to intermittent renewables without significant storage, demand-side management, or dispatchable backup power.
• Confusing nameplate capacity (maximum possible power output under optimal conditions) with actual generation, overlooking the operational load factor.

1. 1Step 1: Create a comparative matrix comparing non-renewable (coal, oil, gas, nuclear fission) and renewable sources across energy density, locational factors, and environmental impacts.
2. 2Step 2: Practice core quantitative questions on load factors, energy efficiency percentages, and payback periods using past AQA exam papers.
3. 3Step 3: Review energy storage and secondary carriers (pumped storage, chemical batteries, green vs grey hydrogen) to understand grid stability solutions.
4. 4Step 4: Draft timed 9-mark evaluative answers focusing on the trade-offs of decarbonising national electricity mixes.

• 📋Data analysis and calculations: Interpreting tables of operational capacities, calculating load factors, fuel efficiencies, or cost-per-kWh comparisons.
• 📋Site selection analysis: Interpreting contour maps, wind rose diagrams, or insolation maps to determine optimal locations for renewable energy schemes.
• 📋Synoptic 9-mark essay questions: Evaluating the viability, environmental consequences, and technological limitations of transitioning from fossil fuels to alternative resources.