C2.2.5 Renewable energy Notes

The Use of Renewable Energy in a Circular Economy

Key Renewable Energy Sources

1. Solar power: from sunlight (e.g. solar panels)
2. Wind power: from turbines
3. Hydropower: from flowing water
4. Geothermal: from heat within the Earth
5. Biomass: from organic material (e.g. wood pellets, biogas)

Solar Energy

1. How it works: Solar panels convert sunlight into electricity using photovoltaic cells.
2. Benefits: Abundant, reduces carbon emissions, and can be deployed at various scales (e.g., residential rooftops, large solar farms).

Example

Noor Ouarzazate Solar Complex – Morocco

• Location: Ouarzazate, Morocco
• Type: Concentrated Solar Power (CSP) and photovoltaic (PV)
• Impact:
  • One of the largest solar power plants in the world
  • Supplies electricity to over 1 million people
  • Helps Morocco reduce reliance on fossil fuels and aims to generate 52% of its energy from renewables by 2030

Wind Energy

1. How it works: Wind turbines convert kinetic energy from wind into electricity.
2. Benefits: Low operational costs and minimal environmental impact once installed.

Example

Horns Rev Offshore Wind Farm – Denmark

• Location: North Sea, off the west coast of Denmark
• Opened: Horns Rev 1 (2002), Horns Rev 2 (2009), Horns Rev 3 (2019)
• Impact:
  • One of the first large-scale offshore wind farms in the world
  • Horns Rev 3 alone powers over 400,000 Danish homes
  • Showcased how offshore wind can deliver stable, large-scale renewable energy

Hydropower

1. How it works: Water flow drives turbines to generate electricity.
2. Benefits: Reliable and efficient, though it can impact local ecosystems.

Example

Three Gorges Dam – China

• Location: Yangtze River
• Scale: World’s largest hydroelectric power station
• Output: Can produce up to 22,500 MW, supplying millions of homes
• Impact: Major renewable energy contributor, though with environmental trade-offs (e.g. ecosystem disruption)

Biomass

1. How it works: Organic materials (e.g., wood, agricultural waste) are burned or converted into biofuels.
2. Benefits: Utilises waste materials and can be carbon-neutral if managed sustainably.

Example

Drax Power Station – United Kingdom

• Location: North Yorkshire
• Use: Europe’s largest biomass power station
• Fuel: Uses compressed wood pellets instead of coal
• Impact: Supplies around 7% of the UK’s electricity, helping reduce carbon emissions

Geothermal Energy

1. How it works: Heat from the Earth's core is used to generate electricity or provide direct heating.
2. Benefits: Consistent and reliable, with a small land footprint.

Example

Iceland – National Power Supply

• Use: About 90% of Iceland’s homes are heated with geothermal energy.
• Impact: Nearly carbon-free heating and electricity generation.
• Why it works: Abundant volcanic activity makes geothermal an ideal local resource.

Why the Circular Economy Relies on Renewables

• Lowers carbon emissions and air pollution
• Supports closed-loop systems with minimal external impact
• Powers recycling, reconditioning, and manufacturing in a cleaner way
• Ensures the full product lifecycle is sustainable, not just the materials

Case study

Tesla’s Gigafactory

Location: Nevada, USA
Renewable Energy: Powered by solar and wind, reducing reliance on fossil fuels
Circular Economy Impact: Manufactures batteries for electric vehicles, enabling low-emission transport and supporting a shift toward sustainable energy systems

Challenges and Considerations

1. Intermittency
   1. Challenge: Solar and wind are weather-dependent and not always consistent.
   2. Solution: Use battery storage and smart grid systems to stabilise supply.
2. 2. High Initial Costs
   1. Challenge: Installing renewable infrastructure can be expensive upfront.
   2. Solution: Long-term savings and environmental benefits usually outweigh the investment.
3. 3. Land and Resource Use
   1. Challenge: Large-scale renewable projects may disrupt land and ecosystems.
   2. Solution: Careful site selection and dual-use land (e.g. solar over farmland) help reduce impact.

The Broader Impact of Renewable Energy

1. Economic Benefits
   1. Job creation: Renewable energy industries create jobs in manufacturing, installation, and maintenance.
   2. Energy savings: Reduces long-term energy costs for businesses and consumers.
2. Social Benefits
   1. Energy access: Off-grid solar solutions provide electricity to remote communities.
   2. Health improvements: Reduces air pollution and associated health risks.
3. Political Benefits
   1. Energy security: Reduces dependence on imported fossil fuels.
   2. Global leadership: Countries investing in renewables position themselves as leaders in sustainability.