7.9 World Energy Use

By the end of this section, you will be able to:
- Describe the distinction between renewable and nonrenewable energy sources.
- Explain why the inevitable conversion of energy to less useful forms makes it necessary to conserve energy resources.

Energy is a crucial component in all phases of society.
Access to adequate and reliable energy resources is essential for:
- Economic growth.
- Maintaining quality of life.
Current levels of energy consumption and production are unsustainable.
Estimated sources of global energy consumption:
- Approximately 31–35% of the world’s energy comes from oil, primarily used for transportation.
- This marks a slight reduction from a decade ago.
- Oil prices fluctuate based on:
- New discoveries of oil.
- Political events worldwide.
The United States, which has 4.25% of the world’s population, consumes 21% of global oil production annually.

Renewable energy sources are those that cannot be depleted, including:
- Water
- Wind
- Solar
- Biomass
Current reliance on renewable energy is low but growing rapidly, notably wind energy.
- Example: Germany aims to meet 65% of its power and 30% of its overall energy needs with renewable resources by 2030.

Approximately 85% of energy consumption is derived from nonrenewable fossil fuels:
- Oil
- Natural gas
- Coal
The combustion of fossil fuels results in carbon dioxide emissions, which many scientists link to global warming.
A shift to non-fossil fuels is considered imperative but challenging.

World energy consumption continues to rise, particularly in developing countries.
- Global energy demand has tripled in the past 50 years and may triple again in the next 30 years.
- Rapid economic growth in China and India is majorly driving this increase.
China surpassed Japan in 2003 as the world's second-largest consumer of oil, relying largely on imports.
- Coal makes up two-thirds of China’s energy consumption.
- In 2009, China became the largest generator of CO2 emissions globally.
India's energy resources primarily include biomass (wood and dung) and coal, with about 70% of its electricity sourced from coal.
- India is also increasing its renewable energy capacity, particularly in wind and solar.
Table 7.6 shows the 2020 commercial energy mix by country, dominating by non-renewable sources, though countries like New Zealand obtain a considerable portion of electricity from hydroelectric power.

Economic well-being is closely linked to energy consumption.
- Higher standards of living (GDP per capita) are associated with higher energy consumption per capita.
- Increased energy efficiency can alter this dependency.
A major global problem is balancing energy resource development with environmental impacts.
- Diversified energy sources can enhance economic opportunity and stability.
- Employment opportunities in renewable energy present sustainable career paths.
- Renewable energy contributes to national resilience against disasters and disruptions.

The concept of energy conservation refers to reducing energy usage through:
1. Reduced activities (e.g., turning down thermostats, driving less).
2. Increased energy conversion efficiencies (e.g., improved vehicle mileage, using energy-efficient lighting).
The law of conservation of energy states that the total amount of energy in an isolated system remains constant.
While energy is conserved, the conversion of energy often leads to waste heat and forms that are not useful for work.
It is crucial to conserve energy because:
- Energy transformations often degrade useful energy.
- Understanding the degradation potential underscores the importance of resource conservation in society.