Renewable Energy

• Solar Cells (PV CELLS) and Decentralized Power
• How electricity is distributed in the traditional power grid
• Pro’s of traditional power grid:

  • Reliable energy 24/7
  • Scalable so as demand increases, more power plants and transmission lines can be added
• Con’s of traditional power grid:

  • Uses conventional energy sources
  • Expensive to expand
  • Power lines are hazards
• Batteries can be added to the system to store the energy produced during the day for use at night (e.g. Tesla Power Wall)
• Currently, adding batteries for energy storage is very expensive

  • Batteries use rare metals like Cobalt, which is not sustainable to mine and is extremely limited in supply
• Decentralized power grid
• Pro’s of decentralized power grid:

  • Renewable
  • Easily expandable as demand increases
  • Much lower cost over time
• Con’s of decentralized power grid:

  • High initial set-up cost
  • Energy storage for night is variable
• In summary, Decentralized Solar systems can reduce our dependence on fossil fuels but not replace them completely, at least not yet
• Types of Renewable Energy:

  • Solar
  • Water
  • Wind
  • Biomass (burning, conversion to liquid fuels)
  • Geothermal
  • Solar-Hydrogen
• Key Limitations of Renewable Energy:

  • Geographic (location) limitations
  • Seasonal Variation
  • Day vs Night Variation
• Reasons why we still depend heavily on conventional energy sources:

  • Conventional sources are more reliable
• Direct Solar Energy is used to:

  • Heat houses and buildings
  • Heat water
  • Create high temperature heat
  • Create electricity
• Passive Solar design maximizes sun's heating and cooling potential in buildings
• Solar Thermal Electricity:

  • Solar Farms use solar collectors to heat a fluid and make steam for electricity production
• Solar Electricity/Decentralized Power Production:

  • Photovoltaic cells or solar cells convert sunlight into electricity
• Hydrogen gas combustion can be used to fuel internal combustion engines and is made from water, needing an energy source to split the water
• Methods of creating electricity include:

  • Biomass Energy
  • Wind Energy
  • Hydropower
  • Waves & Tides
• Wind power is created by wind turbines in Wind Farms located in high wind areas

  Hydroelectric Power involves building dams across rivers to create reservoirs and produce electricity
• Geothermal Energy is produced where hot magma beneath the surface creates hot springs and geysers
• Cons of Hydroelectric Power:

  • Changes cold water stream to warm water lake
  • Affects downstream ecosystems
  • Disrupts natural flood cycles and salmon migrations
• Methods of using Biomass Energy:

  • Burning directly
  • Conversion to gaseous or liquid biofuels (CNG, Ethanol, Biodiesel)
• Pollutants from burning Biomass include wood smoke containing particulates and aromatic hydrocarbons, leading to health issues
• Biogas can be produced from landfills, livestock, and sewage treatment plants

  Ethanol can be produced from grain crops or sugar cane

  Biodiesel can be produced from soybeans
• Biogas from Landfills decomposes trash and waste to produce energy

  Anaerobic Sludge Digester converts solid waste into biofuel
• Ethanol Pros:

  • Existing engines can be easily modified
  • Domestic production
  • No net CO2 emissions
  • Existing infrastructure
• Ethanol Cons:

  • Not as efficient as gas
  • Corn subsidies in the U.S.
  • Transportation impacts
  • Environmental impacts of increased agriculture
• Energy Solutions include Conservation measures like carpooling, line-drying clothes, and avoiding appliance use during peak hours
• Renewable energy sources are methods of producing power for electricity or transportation that are continuously available to human societies
• Renewable energy sources are either directly linked to the sun or indirectly linked to the sun
• Geothermal electricity generation uses heat from the earth's core and tidal power uses the gravitational pull of the moon on the hydrosphere to produce electricity
• Most renewable energy sources are considered alternatives to fossil fuels
• The global community is transitioning to alternative sources of energy due to ecological and economic impacts of conventional energy sources
• Direct Solar Energy:

  • Primary application is using the sun as a heat/light source for buildings directly
  • Designing buildings to maximize the sun's heating potential reduces dependence on fossil fuel energy sources
  • Reduces environmental problems associated with fossil fuels and heating costs
  • Goal is to supplement fossil fuels with sun to make energy infrastructure more sustainable
• Passive Solar Designs:

  • Utilizes the sun's energy for heating buildings directly
  • Reduces dependence on fossil fuels for heating
  • Limitation: effectiveness depends on building design and location
  • Advantage: reduces environmental impact and heating costs
• Solar Water Heating:

  • Uses solar energy to heat water for various purposes
  • Reduces reliance on traditional water heating methods
  • Limitation: initial installation cost
  • Advantage: energy-efficient and reduces utility bills
• Solar Cells (Photovoltaic cells):

  • Convert sunlight into electricity
  • Widely used for residential and commercial electricity generation
  • Limitation: high initial cost
  • Advantage: renewable and clean energy source
• Solar Thermal Electricity:

  • Uses direct sunlight to generate electricity on a large scale
  • Different from other solar applications
  • Limitation: requires specific infrastructure
  • Advantage: sustainable energy production
• Decentralized Energy Infrastructure:

  • Power delivery system differs from centralized systems
  • Explores economic and environmental benefits of decentralized systems
  • Advantages include improved efficiency and reduced environmental impact