Geography (9696) | Sustainable energy supplies

Welcome to Environmental Management: Sustainable Energy Supplies

Hi Geographers! This chapter, Sustainable Energy Supplies, is incredibly important because energy powers everything we do—from charging your phone to lighting entire cities. But how we get that energy determines the future of our planet.

In these notes, we'll break down where energy comes from, what factors stop countries from using clean energy, and the massive environmental consequences of our current choices. Don't worry if this seems like a huge topic; we will tackle it step-by-step using clear language and real-world examples!

Section 1: Classifying Energy Resources

The first step in understanding energy is knowing the difference between the two main categories.

1.1 Non-Renewable Energy Resources (Finite Stock)

These are resources that are used faster than they can be naturally replaced. Once they are gone, they are gone forever—like the money in your pocket that you spend on snacks!

• Fossil Fuels: Coal, oil, and natural gas.
  These were formed millions of years ago from dead plants and animals. They release significant amounts of carbon dioxide (CO₂) when burned.
• Nuclear Power: Uses elements like Uranium.
  While Uranium itself is finite (non-renewable), the energy produced per unit is massive. It creates hazardous waste but does not produce greenhouse gases during operation.

Key Takeaway: Non-renewables currently provide the vast majority of the world's energy, but they are unsustainable due to limited supply and high pollution output.

1.2 Renewable Energy Resources (Sustainable Flow)

These resources are naturally replenished over short time scales and are considered environmentally friendly as they typically produce little to no greenhouse gases.

• Hydroelectric Power (HEP): Energy from moving water (dams).
• Wind Power: Energy captured by turbines.
• Solar Power (Photovoltaic/Thermal): Energy captured from the sun.
• Geothermal Energy: Heat harnessed from within the Earth (common in volcanically active areas, e.g., Iceland).
• Biofuels: Energy derived from organic matter (plants, manure, crops).

Did you know? Wind and solar power are often called "intermittent" sources, meaning they only generate electricity when the sun is shining or the wind is blowing. This makes relying solely on them challenging!

Section 2: Factors Affecting National Energy Supplies and Demand

When a country decides what energy to use, it's a complicated balancing act involving many different factors. We call this the national energy balance.

2.1 Economic and Development Factors

A country's wealth and stage of development are crucial determinants of energy use.

• Levels of Development & Income:
  • HICs (High Income Countries): Have high energy demand per capita (per person). They have the capital (money) and technology to invest in complex, high-cost renewable schemes (e.g., offshore wind farms).
  • LICs (Low Income Countries): Have low energy demand per capita. They often rely on traditional fuels like wood or charcoal (biomass) and cannot afford large infrastructure projects.
• Technology:
  • Advanced technology (e.g., smart grids, battery storage) makes renewable energy more efficient and reliable. Only wealthier nations can afford this investment initially.
  • However, solar panel costs are dropping globally, making decentralized energy accessible even in poorer, remote areas.

2.2 Geopolitical and Security Factors

Security is about ensuring a reliable, uninterrupted supply of energy.

• Energy Security: A country wants reliable and affordable energy. If a country relies too heavily on oil imports from an unstable region, their energy security is low. Diversification (using many different sources) increases security.
• Resource Endowment: What natural resources does the country have?
  • Example: Norway has lots of HEP potential and oil/gas reserves. They focus on these.
  • Example: A desert country might have excellent solar endowment.
• Energy Policy: Government decisions dictate the balance.
  Policies might include subsidies (money to encourage) for solar panels or carbon taxes (fees to discourage) for polluting industries.

2.3 Environmental and Climate Factors

These factors relate directly to sustainability and impact.

• Sustainability: The need to meet today’s energy needs without compromising the ability of future generations to meet theirs. This requires shifting towards renewables.
• Pollution (Local and Global): Burning fossil fuels creates smog and releases greenhouse gases. Energy choices must balance economic growth with pollution control.
• Climate: Affects energy demand (heating/cooling) and supply (solar works better in sunny climates, HEP depends on rainfall).

Section 3: Trends in Global Energy Consumption

Global energy usage patterns show significant differences depending on the development level of the countries involved.

3.1 Consumption Trends of Fossil Fuels

Fossil fuels remain dominant globally, but their consumption trends are shifting based on development:

• HICs: Consumption is often stable or slowly decreasing. Coal usage has declined significantly, replaced by natural gas (which burns cleaner) and increasing renewables.
• MICs (e.g., China, India): These countries are experiencing rapid industrialisation and urbanisation. Energy demand is surging, leading to massive growth in fossil fuel consumption, particularly coal, as it is often cheap and readily available locally.
• LICs: Fossil fuel consumption is low, but rising slowly as they develop transport infrastructure. A large proportion of primary energy comes from traditional biomass.

Common Mistake Alert! Do not assume HICs are now 100% renewable. While their *share* of renewables is growing, they still consume vast amounts of oil and gas.

3.2 Nuclear Power Trends

Nuclear power is a controversial energy source.

• Trend: Generally stable or slow growth globally, though specific countries (e.g., France, China) maintain heavy reliance or are building new plants.
• Concerns: Public fear (following disasters like Chernobyl or Fukushima), very high initial construction costs, and the challenging long-term storage of radioactive waste.

3.3 Trends in Renewable Energy

A. Hydroelectric Power (HEP)

• How it works: Water stored in a reservoir (behind a dam) is released through turbines to generate electricity.
• Trend: Stable, established technology. It provides major base-load power (reliable 24/7). However, the best sites have often already been exploited, and large dams face serious environmental and social opposition (e.g., Three Gorges Dam, China).

B. Wind Power

• How it works: Kinetic energy from wind turns turbines.
• Trend: Rapid growth worldwide, especially in HICs and MICs (e.g., Germany, USA, China). Costs have fallen dramatically. Offshore wind is growing as it is more consistent and causes less visual pollution.

C. Biofuels

• How it works: Crops (like corn, sugar cane, or palm oil) are grown and processed into liquid fuel or burned to generate heat/power.
• Trend: Increasing, often driven by government mandates (requiring fuels to contain a percentage of biofuel).
• Controversy: Biofuels compete with food production for land, driving up food prices (the "food vs. fuel" debate) and potentially leading to deforestation to clear land for crops (e.g., palm oil in Indonesia).

Key Takeaway: The global trend is towards diversification, with a rapid rise in wind and solar, while fossil fuels, particularly coal in industrialising nations, remain crucial.

Section 4: Environmental Impacts of Energy Production and Usage

Energy systems have impacts at every stage, from where they are produced to how they are used. We must consider both local (site-specific) and global (worldwide) impacts.

4.1 Impacts of Production and Transport (Local Scale)

Energy extraction and the infrastructure needed to move it cause local damage:

• Habitat Destruction:
  • Mining (coal, uranium) destroys landscapes and creates spoil heaps.
  • Large HEP dams flood vast areas, destroying ecosystems and displacing communities.
• Water Pollution:
  • Fracking (for natural gas) requires huge volumes of water and risks contaminating local groundwater with chemicals.
  • Oil spills during drilling or transport (e.g., pipeline leaks, tanker accidents) devastate coastal and marine environments.
• Visual and Noise Pollution: Wind farms are sometimes opposed because they are considered unsightly (visual pollution) or generate noise.

4.2 Impacts of Usage (Local and Global Scales)

Local/Regional Pollution (Air Quality)

When fossil fuels are burned in power stations or vehicle engines, they release harmful pollutants like nitrogen oxides (\(NO_x\)) and sulfur dioxide (\(SO_2\)).

1. These gases mix with water vapour in the atmosphere.
2. They form dilute sulfuric and nitric acids.
3. The result is acid rain, which damages forests, corrodes buildings, and acidifies lakes, threatening aquatic life.

Global Impact (Climate Change)

The most severe global impact of energy usage is the contribution to the enhanced greenhouse effect and subsequent global warming.

• Process: Burning fossil fuels releases massive amounts of carbon dioxide (\(CO_2\)), a key greenhouse gas.
• Consequence: This gas forms a blanket around the Earth, trapping heat that would normally escape into space, leading to rising global temperatures, changing weather patterns, and sea-level rise.

Comparing Impacts (Sustainability vs. Damage)

Even seemingly "clean" renewables have impacts:

• Solar farms require large areas of land, impacting ecosystems.
• Manufacturing solar panels and wind turbines uses energy and raw materials (metals and rare earth minerals).

The key geographical argument is that while renewables cause local environmental damage during production, they dramatically reduce the global, catastrophic impacts associated with fossil fuel usage.

Quick Summary: Sustainable Energy

Achieving a sustainable energy supply requires balancing The Energy Trilemma:

1. Energy Security (Can we rely on it?)
2. Energy Equity (Can everyone afford it?)
3. Environmental Sustainability (Does it protect the planet?)

No single energy source currently satisfies all three perfectly, requiring complex policy trade-offs by governments worldwide.