Renewable energy

Renewable energy

1. Geothermal energy

   • What is?
     • It is the energy gotten from the heat generated in the Earth's core.
   • Uses
     • To produce electricity
     • To warm or cool buildings and houses
   • How is it gotten?
     • Geothermal energy can be gotten through two ways
       • Geothermal heat pumps
         • They take the heat from the ground and transfer it to buildings or houses to warm or cool them
       • Geothermal power plant
         • Types
           • Dry steam plant
             • They use steam from a geothermal reservoir to turn on generator turbines that then generate electricity
           • Flash steam plant
             • They use high-pressure hot water from the Earth and convert it into steam. After that, the steam activates the generator turbines that then generate electricity
           • Binary cycle power plant
             • They transfer heat from geothermal hot water to another liquid. This heat causes the other liquid to turn into steam. This steam is later used to activate the generator turbines that are going to produce electricity
   • Advantages
     • It is environmentally ecofriendly; it produces less carbon dioxide than other energy sources, for example oil, coal or natural gas.
     • In the long-term, it is cheaper than conventional energy
     • It is always available
   • Disadvantages
     • Its production is limit to areas close to tectonic plate boundaries
     • It releases a gas called hydrogen sulphide, which smells very bad
     • Its drilling and exploration can cause small earthquakes
     • The costs to build a geothermal power plant are very high

2. Biomass energy

   • What is it?
     • It is the energy obtained from biomass and organic matter
       • Examples
         • Plants
         • Animals
   • Uses
     • To produce liquid fuels, called biofuels
       • They are easy to transport
       • They have a high density energy
       • They are used to power vehicles
       • Examples
         • Ethanol
           • It is a type of alcohol
           • It is made from biomass with huge amounts of carbohydrates
           • It is used as a gasoline additive
         • Biodiesel
           • It is produced from vegetables and animal fats
           • It is used as a fuel for vehicles or as a fuel additive
   • Advantages
     • It produces less carbon than other energy sources
     • It is always available
     • Its production is abundant because the Earth has a huge amount of biomass products and organic matter
     • We can recycle waste by using it to produce biomass energy
   • Disadvantages
     • Its production can damage the environment by releasing huge amount of carbon dioxide into the atmosphere and causing deforestation
     • It is very expensive because of the costs to build a biomass energy plant and to transport and storage biomass and organic matter
   • How is it gotten?
     • Biomass energy is gotten through different processes which, in few words, burn biomass sources
       • Direct combustion
         • Biomass is burned directly
       • Thermochemical conversion
         • Biomass is heated in pressurized vessels called gassifiers, using decomposition processess
       • Transesterification
         • It is a process in which vegetables oils, animal fats and greases are converted into acid methyl esters

3. Water energy

   • What is it?
     • It is the energy obtained from moving water
   • Uses
     • To produce electricity
     • To control floods
     • To avoid drought
     • It is used for recreation purposes
   • How is it gotten?
     • Water energy is gotten using different mechanisms which start to move water, obtaining its energy
       • Dam
         • It is going to retain water from a lake, river or water reservoir. Then, after some time, water is going to be released. In that way, water begins to move, moving turbines that then generate electricity
   • Advantages
     • It is environmentally ecofriendly; it doesn't produce greenhouse gases
     • In the medium and long-term, it is one of the cheapest energy sources of all
     • It reduces the risk and amount of floods of the area in which the dam is located
   • Disadvantages
     • Dams can affect water quality negatively, destroy habitats and kill flora and fauna
     • The costs to build a dam are very high
     • It depends a lot on the amount of rainwater that is available. So, in places that don't rain a lot, the water energy production can be affected in a very bad way

4. Solar energy

   • What is it?
     • It is the energy obtained from the heat and rays of the sun
   • Uses
     • To produce electricity
     • To produce light
     • To heat water
     • For industrial purposes
   • Advantages
     • It is environmentally ecofriendly; it doesn't produce greenhouse gases or pollution
     • The maintenance of the different solar systems is cheap and easy to do it
     • Using a solar system helps you to reduce the amount of money you pay for the water and the electricity
   • Disadvantages
     • The initial costs for producing it are very high
     • It depends on the sunlight and heat. Because of that, when there are cloudy, foggy or humidity periods, its performance, use and effectiveness can be impact in a negative way
   • How is it gotten?
     • Solar energy is going to be gotten through different systems that are going to use the sun to produce energy
       • Solar water heating system
         • It is a system which has the main objective of heating water, for then being used or stored. They are composed of storage tanks and solar collectors
           • Types
             • Passive
               • It uses high pressure water to move other water from the solar collector to the storage tank
               • They are cheaper than an active solar water heating system
             • Active
               • It uses an electric pump to circulate the water from the solar collector to the storage tank
               • They are more effective than passive solar water heating systems
       • Solar-electric systems
         • It converts the sunlight into electricity
         • Parts
           • Modules
             • They transform the sunlight into electricity
           • Inverters
             • They transform the electricity produced in the modules into alternative current, so it can be used by most of the house appliances
           • Batteries
             • When it is produced by the system an excess amount of electricity, the batteries are going to store some of it
           • Wires
           • Circuit breakers
           • Support structures
       • Solar thermal electric systems
         • It converts the suns heat into electricity, thanks to some mirrors which are going to transfer the suns heat into a receiver. Then, the receiver is going to transfer the heat to a conventional engine-generator that then is going to produce electricity

5. Wind energy

   • What is?
     • It is the energy obtained from the wind
   • How is it gotten?
     • Wind energy is gotten from a simple mechanism called wind turbine
       • It is a huge structure that has a the top a turbine with blades which is attached to a central hub. The central hub is connected to a shaft that is going to power a generator
         • When there is wind, the turbine begins to move, making the shaft to power the generator that then produce electricity
   • Uses
     • To produce electricity
     • To pump water for agricultural purposes
   • Advantages
     • Wind turbines can work for a long time
     • Wind turbines can be placed in many types of areas, such as urban, rural and off-grid areas
     • It doesn't produce greenhouse gases
     • Its production is very cheap
     • Its production helps for giving new jobs to thousands of people
       • Examples
         • Installers
         • Manufacturers
         • Technicians
   • Disadvantages
     • Wind turbines produce a lot of noise, which can be very annoying
     • Wind turbines can affect the visual aspect of the environment in a negative way
     • Its production depends exclusively on wind, which can be a problem when there are periods of few wind or when the movement of wind is slow
     • It can affect wildlife. The reason why is because flying creatures, such as birds or bats, constantly crush with wind turbines, killing them

6. It is a type of energy that never ends because it is constantly renewed