Energy Efficiency and Sustainable Power Generation

The Energy Problem and Conversion Processes

The energy problem: In any energy conversion, part of the energy is lost as heat (energy degradation). Primary energy sources are contained in energy.

Primary and Final Energy Consumption

Final energy: The energy used at primary consumption points. Final energy is calculated as primary energy minus energy lost in transport and other operations.

Household Energy Consumption Patterns

Regarding energy consumed in Spanish homes, petroleum and petroleum products represent one-third of the energy used. Electricity represents another one-third, followed by natural gas and coal (which is currently phasing out).

Factors Influencing Domestic Energy Use

Power consumption depends on:

• The climatic area
• Insulation quality
• The quality of home equipment
• The degree of efficiency

Thermal Power Plants

Electric energy is produced from the chemical energy of a fuel, such as oil, coal, or natural gas.

Advantages and Disadvantages of Thermal Stations

Pros:

• Operation does not depend on meteorological conditions.
• The underlying technology is very developed.
• Transportation of fossil fuels for power is easy and relatively cheap.
• User access is very easy.
• Energy is clean, versatile, and generates no waste at the point of use.

Disadvantages: These plants have a great environmental impact.

Nuclear Energy and Power Generation

Energy is released in the fission of the atoms of heavy elements, such as uranium and plutonium. Thermonuclear power plants produce electric power using uranium as a primary source of energy, which is non-renewable.

The Nuclear Debate: Risks and Solutions

The nuclear issue:

• The risk of accidents in nuclear plants.
• Nuclear waste produced in the facilities.
• The risk of using nuclear technology for the development of weapons.

The nuclear solution:

• Nuclear power stations are less polluting than some alternatives.
• They continuously generate energy at reduced costs compared to other plants.
• They can reduce dependence on petroleum.
• Provided with adequate security measures, the probability of an accident is very low.

Renewable Energy Sources

Types of Renewable Energy Systems

• The Sun: A direct source of solar energy.
• Biomass: Organic matter of vegetable or animal origin which can be used energetically; fermentation produces certain waste biofuels.
• The Air: Takes advantage of wind energy to move the blades of wind turbines on wind farms and produce electrical energy.
• The Water: Hydroelectric power plants take advantage of the drop of water on the blades of the turbine to produce electrical energy.
• Other sources: Tidal energy (the effect of tides) and geothermal energy (thermal energy accumulated in the subsoil).

Pros and Cons of Renewable Energy

Advantages:

• Very small environmental impact.
• Reserves do not deplete.
• They decrease energy dependence.
• Research contributes to scientific development.

Disadvantages:

• Very expensive to implement.
• They do not guarantee a stable supply.
• There is a small percentage of negative environmental impact.
• They currently meet only a small percentage of demand.