EARTH SCIENCE

• Geothermal energy is a renewable energy produced from the heat inside the earth
• Volcanoes, geysers, and hot springs are visible signs of large amount of heat lying in the earth's interior
• Geo means earth and thermus means heat in Greek
• The Philippines ranked second in the world's s production of geothermal energy
• In terms of electricity generation, 41.4% of the electricity demand is met by geothermal energy, 28% by coal, 11.4% by hydro, 15% by natural gas and 0.1% by wind, solar and biofuel.
• Geothermal energy is generated in two ways; geothermal power plants and geothermal heat pumps
• The three main types of geothermal power plants are dry steam power plant, flash steam power plant, and binary cycle power plant
• This type of power plant uses hot steam from underground reservoirs to generate electricity
• This type of power plant pumps hot water rather than steam directly to the surface and has a flash tank
• This type of power plant has heat exchanger with working fluid/liquid
• The geothermal power plant in Leyte is taking part in boosting the power supply of Cebu - Panay - Negros power grid
• The biomass and fossil fuels are non-renewable resources in the philippines
• The similarities of the three types of power plants is they have a turbine, generator, injection well, and load
• The Open loop system simply pulls water up, run it through the heat pump to add heat in summer, and remove heat in the winter, and then recycles it back into the aquifer and is controlled manually
• Closed-loop system has the same function, except a loop of tubing is buried underground and filled with fluid, usually anti-freeze. These systems work well in areas with moderate climates and can be controlled by a device
• The Horizontal Loop where space allows, the sealed piping loop can be buried in trenches ranging from 3 to 6 feet deep.
• The Vertical Loop where space is limited, the sealed piping loop can be inserted in small holes ranging from 150 to 400 feet deep that are installed using a well-drilling rig.
• The Pond Loop is when a nearby body of water is available, the sealed piping loop can be submerged under the surface.
• The Well Water where groundwater is of adequate quantity and quality, well water can be directly used instead of the sealed piping loop.
• The closed-loop system uses a sealed network of pipes filled with a special fluid called propylene glycol
• The Open loop system uses water as a fluid in the loop that is being drawn from the well or water source. It is circulated through the heat pump and is released back to the ground or a body of water
• The advantages of the Open loop system is that it is efficient but requires water source
• The advantages of the closed-loop system is that it is more versatile working in various locations in climates
• Geothermal heat pumps are energy-efficient, environmentally friendly, and comfortable all year round
• A geothermal heat pump system is installed near the surface of the earth, typically making use of the Earth's heat at a depth of only 5 to 200 feet (1.5 m to 61 meters),
• A geothermal heat pump system does not depend on a geothermal reservoir. These geothermal systems can be used almost everywhere in the world.
• There are four basic components of the heat pumps. These are Evaporator, Compressor Condenser, and Expansion device