🌿Intro to Environmental Science Unit 10 – Energy Resources & Renewable Energy

Key Concepts

• Energy resources are sources of energy that can be harnessed to perform work, generate electricity, or provide heat
• Renewable energy sources are replenished naturally and include solar, wind, hydro, geothermal, and biomass
  • These sources are considered sustainable and have a lower environmental impact compared to non-renewable sources
• Non-renewable energy sources are finite and will eventually be depleted, such as fossil fuels (coal, oil, and natural gas) and nuclear energy
• Energy efficiency involves using less energy to perform the same task, reducing waste and conserving resources
• Greenhouse gases, such as carbon dioxide (CO2), are released during the combustion of fossil fuels and contribute to climate change
• Energy conservation involves changing behaviors and habits to reduce energy consumption and minimize waste

Types of Energy Resources

• Fossil fuels are formed from the remains of ancient plants and animals, and include coal, oil, and natural gas
  • These resources are non-renewable and release greenhouse gases when burned
• Nuclear energy is derived from the splitting of atomic nuclei (fission) or the fusion of atomic nuclei (fusion)
  • Fission is currently used in nuclear power plants, while fusion is still in the experimental stage
• Solar energy harnesses the power of the sun through photovoltaic cells (solar panels) or solar thermal collectors
• Wind energy uses wind turbines to convert the kinetic energy of moving air into electricity
• Hydropower captures the energy of falling or flowing water to generate electricity, often through the use of dams and turbines
• Geothermal energy utilizes heat from the Earth's interior to generate electricity or provide direct heating
• Biomass energy is derived from organic matter, such as wood, agricultural waste, or dedicated energy crops (switchgrass)

Fossil Fuels: Pros and Cons

• Pros:
  • Fossil fuels have a high energy density, meaning they produce a large amount of energy per unit of volume
  • Infrastructure for fossil fuel extraction, processing, and distribution is well-established
  • Fossil fuels are relatively inexpensive compared to some renewable energy sources
• Cons:
  • Burning fossil fuels releases greenhouse gases, contributing to climate change and air pollution
  • Fossil fuels are non-renewable and will eventually be depleted
  • Extraction of fossil fuels can have negative environmental impacts, such as oil spills and habitat destruction
  • Dependence on fossil fuels can lead to geopolitical tensions and energy insecurity

Renewable Energy Sources

• Solar energy advantages include its abundance, low operational costs, and minimal environmental impact
  • Challenges include intermittency (dependent on weather conditions) and the need for energy storage solutions
• Wind energy is a clean and increasingly cost-competitive source of electricity
  • Challenges include intermittency, noise pollution, and potential impacts on wildlife (birds and bats)
• Hydropower is a reliable and flexible source of electricity, but can have significant environmental impacts (altered river ecosystems and fish populations)
• Geothermal energy provides a consistent and reliable source of electricity or direct heating
  • Limited to specific locations with suitable geothermal resources
• Biomass energy can be carbon-neutral if sustainably managed, but may compete with food production and have land use implications

Environmental Impacts

• Burning fossil fuels contributes to air pollution, releasing particulate matter, nitrogen oxides (NOx), and sulfur dioxide (SO2)
  • These pollutants can have negative impacts on human health (respiratory issues) and the environment (acid rain)
• Greenhouse gas emissions from fossil fuels are the primary driver of climate change
  • Climate change impacts include rising sea levels, more frequent and intense extreme weather events, and shifts in ecosystems and biodiversity
• Renewable energy sources generally have lower environmental impacts compared to fossil fuels
  • However, they can still have some negative effects, such as land use changes, habitat disruption, and materials used in manufacturing

Energy Efficiency and Conservation

• Energy efficiency involves using technology and processes that require less energy to perform the same task
  • Examples include LED light bulbs, Energy Star appliances, and high-efficiency heating and cooling systems
• Energy conservation involves changing behaviors and habits to reduce energy consumption
  • Examples include turning off lights when not in use, adjusting thermostat settings, and using public transportation or carpooling
• Improving energy efficiency and promoting conservation can help reduce energy demand, lower costs, and minimize environmental impacts

Future of Energy

• The transition to a low-carbon energy system will require a significant increase in the adoption of renewable energy sources
  • This transition will be driven by factors such as technological advancements, policy support, and changing consumer preferences
• Energy storage solutions, such as batteries and pumped hydro storage, will become increasingly important to address the intermittency of solar and wind energy
• Smart grids and demand response technologies will help optimize energy distribution and consumption
• Hydrogen and advanced biofuels may play a role in decarbonizing sectors that are difficult to electrify, such as heavy industry and long-distance transportation
• International cooperation and policies, such as carbon pricing and renewable energy targets, will be crucial in addressing the global challenge of climate change

Case Studies and Real-World Applications

• Germany's Energiewende (energy transition) aims to phase out nuclear power and fossil fuels in favor of renewable energy sources
  • In 2020, renewable energy accounted for over 45% of Germany's electricity generation
• The Geysers in California is the world's largest geothermal field, with a generating capacity of around 1,500 megawatts
• The Itaipu Dam on the Brazil-Paraguay border is one of the world's largest hydroelectric power plants, with a generating capacity of 14,000 megawatts
• The Mojave Desert in California is home to several large-scale solar power projects, including the Ivanpah Solar Electric Generating System
• The Block Island Wind Farm off the coast of Rhode Island is the first offshore wind farm in the United States
• The Net-Zero Energy Residential Test Facility in Maryland demonstrates advanced energy efficiency and renewable energy technologies in a residential setting