GEOTHERMAL-ENERGY-Harnessing the heat from the earth.

A lesson about geothermal energy, geothermal power plants, advantages and disadvantages.

1. ENERGY FROM VOLCANO: GEOTHERMAL ENERGY

2. 01 Describe how geothermal energy is generated 02 Identify the processes involved on how energy is transformed into electricity in geothermal power plant 03 Identify the location of geothermal plant in the Philippines  04 Cite the importance of geothermal energy learning objectives

3. Geothermal Energy Geothermal energy is heat within the earth. The word geothermal comes from the Greek words  geo  (earth) and  thermal  (heat). Geothermal energy is a renewable energy source because heat is continuously produced inside the earth. People use geothermal heat for bathing, for heating buildings, and for generating electricity.

4. Geothermal Energy The Earth is believed to be extremely hot from within. This heat from the Earth’s interior is a source of energy called geothermal energy. The heat of the Earth warms up water which is trapped in rock formations beneath its surface .

5. There are two Geothermal Systems ; a. Conventional Geothermal System utilizes steam from natural resources such as geysers or by drawing water from the hot, high-pressure depths of Earth; and b. Supercritical Geothermal System a naturally occurring hot water or steams flows heated by magma and circulating through permeable rock. In volcanic geothermal energy, the heat comes from supercritical. The energy from supercritical water is much higher than conventional steam.

6. How is geothermal energy generated ? Geothermal energy is generated in two ways: geothermal power plants and geothermal heat pumps. They differ in the depth of heat source to produce energy .

7. How is geothermal energy generated? In geothermal power plants, the heat from deep inside the Earth is used to produce steam to generate electricity. In comparison with geothermal heat pumps, it uses the heat coming from close to the Earth’s surface to heat water or provide heat for buildings.

8. In the Philippines, geothermal power plants are used to generate electricity in Tiwi (Albay), Kidapawan (North Cotabato), Calaca (Laguna), Tongonan (Leyte), Bago City (Negros Occidental), Valencia (Negros Oriental), and Bacon (Sorsogon). Geothermal Power Plants in the Philippines

9. The Geothermal Power Plant Power plants are built in an area where it is particularly hot just below the surface or near a group of geysers, hot springs, or volcanic activity .

10. The following steps are followed to generate electricity in a geothermal power plant: Wells are drilled deep into the earth to pump steam or hot water to the surface. When the water reaches the surface, the drop in pressure causes the water to turn into steam. The steam spins a turbine, which is connected to a generator that produces electricity. Cooling tower cools the steam and condenses it back to water. The cooled water is pumped back into the earth to begin the process again.

11. The ADVANTAGES and DISADVANTAGES

12. Advantages of geothermal energy 1. Environmentally friendly Geothermal energy is generally considered environmentally friendly. The carbon footprint of a geothermal power plant is minimal. An average geothermal power plant releases 99% less carbon dioxide (CO2) for every megawatt-hour ( MHh ) of electricity it generates, according to the Energy Information Administration (EIA).Further development of our geothermal resources is considered helpful in the fight against global warming. 3. Massive potential Geothermal power plants across the world currently deliver just 12.7 gigawatts (GW) of electricity, with installed geothermal heating capacity a bit higher at 28 GW. This means there is a lot of scope for additional geothermal energy generation. 2. Renewable and sustainable Geothermal reservoirs come from natural resources and are naturally replenished. Geothermal energy is therefore a renewable energy source. “Sustainable” is another label used for renewable sources of energy. In other words, geothermal energy is a resource that can sustain its own consumption rate – unlike conventional energy sources such as coal and fossil fuels. According to scientists, the energy in our geothermal reservoirs will literally last billions of years.

13. Advantages of geothermal energy 4. Stable Geothermal energy is a reliable source of energy. Geothermal power plants are therefore excellent for meeting the base load energy demand. Geothermal power plants have a high capacity factor, meaning that they deliver a very high level of output relative to the total installed capacity . 5 . Great for heating and cooling easier way to utilize geothermal energy is to use it for heating and cooling. This approach makes use of the (relatively small) temperature difference between the surface and a ground source. Earth is generally more resistant to seasonal temperature changes than air. Consequently, the ground only a few feet below the surface can act as a heat sink/source with a geothermal heat pump — much in the same way an electrical heat pump uses the heat present in the air.  

14. Disadvantages of geothermal energy 1. Location-specific Good geothermal reservoirs are hard to come by. Some countries have been blessed with great resources – Iceland and Philippines, for instance, meet nearly one-third of their electricity demand with geothermal energy. If geothermal energy is transported long distances by means of hot water (not electricity), significant energy losses have to be taken into account. 2. Expensive Commercial geothermal power projects are expensive. Total installation costs usually end up somewhere between $2.5–$5 million for a geothermal power plant with a capacity of 1 megawatt (MW). The exploration and drilling of new reservoirs play a big role in driving up costs, typically accounting for half of the overall costs. As previously mentioned, most geothermal resources cannot be utilized in a cost-effective manner, at least not with current technology, level of subsidies, and energy prices. 3. Surface instability (earthquakes) The construction of geothermal power plants can affect the stability of the land. In fact, geothermal power plants have led to subsidence (sinking of the Earth’s surface) in both Germany and New Zealand. Earthquakes can be triggered due to hydraulic fracturing, which is an intrinsic part of developing enhanced geothermal system (EGS) power plants. In 2006, the construction of a geothermal power plant in Switzerland triggered an earthquake with a magnitude of 3.4 on the Richter scale.