8.1 Fossil fuels

Fossil fuels have powered human progress for centuries, but their environmental toll is steep. Coal, oil, and natural gas dominate global energy consumption, providing abundant power but releasing harmful greenhouse gases and pollutants.

As we grapple with climate change, the transition away from fossil fuels is crucial. Renewable energy sources are becoming more competitive, but challenges remain in reducing our dependence on these long-established energy sources.

Types of fossil fuels

• Fossil fuels are non-renewable energy sources formed from the remains of ancient organisms over millions of years
• The three main types of fossil fuels are coal, oil, and natural gas, each with distinct formation processes and extraction methods
• Fossil fuels currently dominate global energy consumption but have significant environmental impacts and are finite resources

Coal formation and extraction

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• Coal forms from the burial and compression of plant material in anaerobic conditions over millions of years
  • Peat (partially decayed plant matter) is the first stage in coal formation
  • Increasing heat and pressure convert peat into lignite, subbituminous coal, bituminous coal, and anthracite
• Coal is extracted through surface mining (strip mining, open-pit mining) or underground mining (room-and-pillar, longwall mining)
  • Surface mining is used when coal seams are close to the surface, while underground mining accesses deeper deposits
• Coal mining has significant environmental impacts, including land disturbance, water pollution, and methane emissions

Oil and gas origins

• Oil and natural gas form from the burial of marine microorganisms in sedimentary basins over millions of years
  • Organic matter is converted into kerogen, which then transforms into oil and gas under high heat and pressure
• Oil and gas accumulate in permeable rock formations (reservoirs) capped by impermeable rock layers (traps)
  • Common reservoir rocks include sandstone and limestone, while traps can be structural (folds, faults) or stratigraphic (pinchouts, unconformities)
• Oil and gas are extracted through drilling wells into the reservoir rock, often using hydraulic fracturing (fracking) to increase production

Unconventional fossil fuel sources

• Unconventional fossil fuels are resources that require advanced extraction techniques due to their unique geological characteristics
  • Examples include oil sands (tar sands), oil shale, shale gas, and coalbed methane
• Oil sands are a mixture of sand, clay, water, and bitumen (heavy oil) that require mining or in-situ extraction methods
  • Mining involves removing the oil sands and separating the bitumen, while in-situ methods heat the bitumen underground for extraction
• Shale gas and oil are trapped within low-permeability shale formations and require hydraulic fracturing and horizontal drilling for extraction
• Unconventional fossil fuels have higher extraction costs and environmental impacts compared to conventional sources

Fossil fuel consumption patterns

• Fossil fuels have been the primary energy source for human activities since the Industrial Revolution
• Global consumption of fossil fuels has increased dramatically over the past century, driven by population growth, industrialization, and rising living standards
• The future of fossil fuel demand depends on factors such as economic development, energy efficiency, and the adoption of alternative energy sources

Historical usage trends

• Coal was the dominant fossil fuel in the 19th and early 20th centuries, fueling the Industrial Revolution and steam-powered transportation
• Oil consumption surged in the mid-20th century with the growth of the automobile industry and petrochemical production
• Natural gas usage has increased in recent decades due to its lower carbon emissions compared to coal and its versatility in electricity generation and heating

Current global consumption

• In 2021, fossil fuels accounted for approximately 84% of global primary energy consumption
  • Oil: 31%, Coal: 27%, Natural Gas: 24%
• The United States, China, and India are the world's largest consumers of fossil fuels
• The transportation sector is heavily dependent on oil, while coal and natural gas are primarily used for electricity generation and industrial processes

Projections for future demand

• The International Energy Agency (IEA) projects that global energy demand will increase by 30% between 2020 and 2040
  • Fossil fuels are expected to continue dominating the energy mix, although their share may decrease due to the growth of renewables
• Developing countries, particularly in Asia and Africa, will drive much of the increase in fossil fuel demand as they industrialize and expand access to energy
• Efforts to mitigate climate change and transition to a low-carbon economy may lead to a peak in fossil fuel demand in the coming decades

Environmental impacts of fossil fuels

• The extraction, processing, and combustion of fossil fuels have significant environmental consequences
• Fossil fuel use is the primary driver of anthropogenic climate change due to greenhouse gas emissions
• Fossil fuels also contribute to air and water pollution, land degradation, and biodiversity loss

Greenhouse gas emissions

• Burning fossil fuels releases carbon dioxide (CO2), the most significant anthropogenic greenhouse gas
  • CO2 emissions from fossil fuel combustion and industrial processes account for approximately 78% of the increase in greenhouse gas emissions since 1970
• Methane (CH4) is another potent greenhouse gas released during the extraction and distribution of oil and natural gas
• The accumulation of greenhouse gases in the atmosphere traps heat and causes global warming, leading to climate change impacts such as sea-level rise, more frequent extreme weather events, and ecosystem disruption

Air pollution and health effects

• Fossil fuel combustion emits various air pollutants, including particulate matter (PM), nitrogen oxides (NOx), sulfur dioxide (SO2), and volatile organic compounds (VOCs)
  • PM2.5 (fine particulate matter) is particularly harmful to human health, causing respiratory and cardiovascular diseases
• Air pollution from fossil fuels is linked to millions of premature deaths worldwide each year
• Coal-fired power plants are a major source of mercury emissions, which can bioaccumulate in aquatic food chains and pose health risks to humans and wildlife

Land and water degradation

• Fossil fuel extraction and processing can lead to land disturbance, deforestation, and habitat fragmentation
  • Surface mining for coal and oil sands requires the removal of vegetation and topsoil, disrupting ecosystems and increasing erosion
• Oil spills and leaks from pipelines and tankers can contaminate soil, groundwater, and marine environments
  • The Deepwater Horizon oil spill (2010) in the Gulf of Mexico was the largest marine oil spill in history, causing extensive damage to coastal ecosystems and local economies
• Hydraulic fracturing (fracking) for shale gas and oil can potentially contaminate groundwater with chemicals and methane, and induce seismic activity

Economic aspects of fossil fuels

• Fossil fuels have been a key driver of economic growth and development since the Industrial Revolution
• The costs of extracting, processing, and distributing fossil fuels have significant implications for energy markets and investment decisions
• Subsidies and externalities associated with fossil fuels can distort market signals and hinder the transition to cleaner energy sources

Costs of extraction and processing

• The cost of extracting fossil fuels varies depending on factors such as resource quality, location, and extraction method
  • Unconventional resources like oil sands and shale oil typically have higher extraction costs than conventional sources
• Processing costs include refining crude oil into petroleum products, converting coal into coke for steel production, and treating natural gas to remove impurities
• Transportation costs, such as pipelines and tankers, also contribute to the overall cost of fossil fuels

Subsidies and externalities

• Fossil fuel subsidies are government measures that lower the cost of production or consumption of fossil fuels
  • Subsidies can take the form of direct payments, tax breaks, or price controls
• In 2020, global fossil fuel subsidies amounted to approximately $180 billion, distorting market signals and encouraging overconsumption
• Externalities are costs or benefits not reflected in market prices, such as the environmental and health impacts of fossil fuel use
  • The social cost of carbon (SCC) estimates the economic damages associated with an additional ton of CO2 emissions, which is not typically included in fossil fuel prices

Fossil fuels vs renewable energy

• Renewable energy sources, such as solar, wind, and hydropower, have become increasingly cost-competitive with fossil fuels in recent years
• The levelized cost of energy (LCOE) for utility-scale solar and wind power has fallen by 85% and 56%, respectively, between 2010 and 2020
• However, the intermittency of renewable energy sources and the need for energy storage solutions pose challenges for grid integration and reliability
• Transitioning from fossil fuels to renewables requires significant investments in infrastructure, technology development, and policy support

Sociopolitical dimensions of fossil fuels

• Fossil fuels have shaped geopolitical dynamics and energy security concerns for decades
• The concentration of oil and gas reserves in certain regions has led to political tensions and conflicts
• The fossil fuel industry has significant influence on energy policies and public discourse

Geopolitics of oil and gas

• The Middle East holds approximately 48% of the world's proven oil reserves and 38% of natural gas reserves, making it a strategically important region
  • Conflicts and political instability in the Middle East can disrupt global oil supply and cause price volatility
• Russia is the world's second-largest producer of natural gas and has used its energy exports as a geopolitical tool
  • Europe's dependence on Russian natural gas has raised concerns about energy security and political leverage

Energy security concerns

• Energy security refers to the reliable, affordable, and uninterrupted supply of energy to meet a country's needs
• Countries that heavily rely on imported fossil fuels are vulnerable to supply disruptions and price shocks
  • The oil crises of the 1970s highlighted the economic and political consequences of oil dependence
• Diversifying energy sources, increasing domestic production, and building strategic reserves are strategies to enhance energy security

Fossil fuel industry influence

• The fossil fuel industry has significant lobbying power and influence on energy policies and regulations
  • In the United States, the oil and gas industry spent over $100 million on lobbying in 2020
• Fossil fuel companies have been accused of spreading misinformation about climate change and delaying action on reducing greenhouse gas emissions
  • ExxonMobil, one of the world's largest oil companies, knew about the risks of climate change since the 1970s but publicly downplayed the threat
• The industry's influence can hinder the transition to cleaner energy sources and the implementation of effective climate policies

Transitioning away from fossil fuels

• Reducing dependence on fossil fuels is crucial for mitigating climate change and achieving a sustainable energy future
• The transition to a low-carbon economy faces various challenges, including technological, economic, and political barriers
• Policies and strategies are needed to promote the adoption of renewable energy and energy efficiency measures

Challenges in reducing dependence

• Fossil fuel infrastructure, such as power plants and pipelines, represents sunk costs and can create lock-in effects
  • The long lifespan of fossil fuel assets can delay the retirement of carbon-intensive infrastructure
• Transitioning away from fossil fuels may lead to job losses in the industry, requiring support for affected workers and communities
  • The concept of a "just transition" emphasizes the need for socially equitable and inclusive policies to support workers in the shift to a low-carbon economy
• Resistance from the fossil fuel industry and political opposition can hinder the implementation of climate policies and the growth of clean energy

Policies for promoting alternatives

• Carbon pricing mechanisms, such as carbon taxes and cap-and-trade systems, can incentivize the reduction of greenhouse gas emissions and the adoption of cleaner technologies
  • The European Union's Emissions Trading System (EU ETS) is the world's largest carbon market, covering approximately 40% of the EU's greenhouse gas emissions
• Renewable energy mandates and targets set by governments can drive the deployment of solar, wind, and other clean energy sources
  • California's Renewable Portfolio Standard requires 60% of the state's electricity to come from renewable sources by 2030
• Financial incentives, such as tax credits and subsidies, can encourage investment in renewable energy and energy efficiency projects

Strategies for a low-carbon future

• Increasing energy efficiency in buildings, transportation, and industry can significantly reduce energy demand and greenhouse gas emissions
  • Implementing energy efficiency standards for appliances, vehicles, and buildings can drive technological improvements and cost savings
• Electrification of the transportation sector, through the adoption of electric vehicles and the expansion of charging infrastructure, can reduce oil dependence and tailpipe emissions
  • Norway has the highest share of electric vehicle sales globally, with over 50% of new car sales being electric in 2020
• Developing and deploying carbon capture, utilization, and storage (CCUS) technologies can help reduce emissions from hard-to-abate sectors, such as cement and steel production
• Promoting sustainable land use practices, such as reforestation and soil carbon sequestration, can enhance natural carbon sinks and offset emissions