NASK1_Energie

Energy from Fuels

• Generation: Home electricity is generated by large dynamos in power stations.

• There are three types of Fossil Fuels: oil, natural gas, and coal. Fossil fuels are the primary energy source in the Netherlands.

  • Other sources, such as wind, nuclear, and solar energy, are less significant.

Applications of Fuels

• Heating of Buildings: Fuels provide heat for homes, shops, and offices, primarily using natural gas for central heating.

• Transportation: Fuels power cars, trucks, and jet engines (which use kerosene).

• Electricity Generation: Most power stations in the Netherlands run on natural gas, with some using coal.

Electricity Generation from Fuels

1. Energy Conversion: Chemical energy from fuels converts into heat when burned.

2. Power Station Process:

   • Natural gas burned in large burners heats water, producing high-pressure steam.

   • Steam drives the blades of a steam turbine, causing it to rotate.

   • A generator connected to the turbine produces electrical energy, similar to a dynamo.

   • Steam is cooled down in a condenser, condensing back into water for reuse.

3. Waste Heat: Not all chemical energy is converted to electrical energy; excess heat is termed waste heat.

Energy Flow and Efficiency in Power Plants

• The energy flow diagram shows the conversion of chemical energy to electrical energy:

  • Approximately 40% converts to electrical energy, while 60% is waste heat.

• Waste heat removal:

  • Discharged into rivers under strict regulations or cooled in cooling towers first.

Reusing Waste Heat

• Useful applications of waste heat are being explored:

  • Example: In Meppel, waste heat from a concrete factory heats a swimming pool, reducing energy consumption.

Measurement of Energy

• Energy Units: Energy is measured in joules (J), with larger measurements in kilojoules (kJ) and megajoules (MJ).

  • 1 kJ = 1000 J, 1 MJ = 1,000,000 J.

• Kilowatt-hour (kWh): Commonly used by energy companies, convertible with:

• 1 kWh = 3.6 MJ.

• Example Calculation: An average Dutch family uses 3,500 kWh/year, which equals 12,600 MJ. (3,500 × 3.6)

Wind Energy

• Kinetic Energy: The movement of objects gives them kinetic energy.

  • Heavier objects (higher mass) have more kinetic energy due to speed and mass.

• Use in Windmills: Wind turbines convert the kinetic energy of wind into electrical energy via rotating blades and electric generators.

  • Components: Blades, gearbox, generator, and transformer to increase voltage for efficient transmission.

Power of Wind Turbines

• Power Measurement: 1 watt (W) = 1 joule (J) per second.

  • Example: A 3 MW (3 million watt) turbine can deliver 3 MJ of energy/second in optimal conditions.

• Wind Force Relationship: Turbines reach maximum output at a certain wind force, with control mechanisms to prevent exceeding limits.

Comparing Energy Sources

• Cost: Wind electricity is currently more expensive than fossil fuels.

• Availability: Fossil fuels can be continuously available unlike wind energy, which depends on weather.

• Environmental Impact: Fossil fuels generate waste, while wind energy is cleaner but may cause noise and landscape issues.

Solar Energy

• Energy Yield: Solar panel output depends on weather; more energy on sunny days.

• Nature of Solar Energy: Sunlight is vital for life; it's converted into thermal energy (radiant energy) that heats the atmosphere and earth's surface.

Solar Collectors and Panels

• Solar Collector Function:

  • Black plate absorbs sunlight to heat water in pipes.

  • Insulation minimizes heat loss.

  • Heated water is used in homes post-heat exchange.

• Solar Cells: Convert radiant energy directly into electrical energy.

  • Optimal performance: 190 W power under perfect conditions.

  • Applications: Installation in remote areas or by environmentally-conscious consumers.

Efficiency of Solar Panels

• The average solar panel efficiency is around 17%.

  • Research is ongoing to improve efficiency with multi-layer solar cells to reach up to 50%.

• Efficiency Calculation:

  • Employed formulas for assessing energy yield and efficiency in solar power generation.

Biofuels

• Biofuels like ethanol, biodiesel, and biogas are generated from plant or animal materials, capturing solar energy through photosynthesis.

• Considerations include resource allocation (food crop vs waste).

Hydropower

• Hydroelectric Power: Generated from reservoirs in high-altitude areas.

• Operation of Hydropower Plants:

  • Water flows from reservoirs through turbines, converting gravitational energy to electrical energy.

  • The energy production process highlights the mass of water and height difference as key factors.

• Efficiency Assessment: Use of gravitational energy formulas to measure efficiency.

Tidal Energy

• Utilizes ocean tides for energy production, effective in bays with significant tidal differences.

• The process involves damming water and generating electricity when the tide flows out.