GEOTHERMAL ENERGY

1.INTRODUCTION
Geothermal energy use the internal heat from the earth.
The internal Earth is divided into three layers the heat
increase at the same time we deepen so there is a big
thermal gradient and a heat flow to the exterior. This flow is
used to obtain energy.
It is a clean and renewable energy
2.THEORICAL BASICS
TYPES
There are two types of geothermal deposits:
-Dry deposits:
+It is an area on the Earth with hot materials or
stones in dry.
+It is injected water for a recovered drill and its get
hot
+The heat is used by means of a heat exchanger
and the water is rejected.
-Hot water deposit:
+These sites can form a source ( used as thermal
baths ) or be underground ( serve to capture the heat
From inside the Earth ) .
+There are four types depending the temperature of
water:

High Temperature (150-400 degrees): Steam is
produced at the surface and through the turbine
generates electricity. Several conditions are required for
the possible existence of a geothermal field occurs: an
upper layer comprising a cover impermeable rock,
aquifer, or reservoir, of high permeability; fractured soil
allowing convective fluid flow, and therefore the heat
transfer from the source to the surface, and a heat
source magmatic
Medium Temperature (70-150 degrees): The
steam-electric conversion is performed with a lower
yield, and be exploited by means of a volatile fluid. These
sources allow small power plants explode, but the best use
can be made by urban heat delivery systems for use in
heating and cooling
Low temperature (50-70 degrees):is usable in wider
areas than earlier, in all sedimentary basins. Is due to
the geothermal gradient.
Very low temperature (20-50 degrees) :This energy
is used for domestic, urban and agricultural needs,
such as geothermal HVAC (geothermal heat pump).

How it works
Geothermal energy use the heat from the internal Earths
heat to produce energy,how?
-First we drill the zone (near tectonic zone) to get the heat
we use injection well.
-After that the water goes from the Earths surface up this
water moves the turbine which convert it into energy
-Finally, water returns by recovery well and the process re-
start.
Facilities
There are two types or facilities depending of the system of
catchment used in the extraction of geothermal energy:
Horizontal:
-Near to the surface (1-2 meters)
-Depends of the variation of the ambient temperature.
-It occupies lots of space
-It is used for little power because vertical facilities have
more power.
Vertical
-Perforations between 50 and 200 meters (far to the
surface)
- Dont depends of the variation of the external temperature
-It has a biggest cost
-It occupies less space than horizontal





3.ADVANTAGES
Its a source that would avoid dependence on foreign
energy.
No noise
Cheap energy, because it is not subject to
international prices.
No destruction. The land to build geothermal plant is
smaller than the other plants need so no forest
clearance is needed, or builds storage tanks.
Minimal residues, mostly takes advantage causing
less environmental impact caused by the oil and coal.
Big savings, both economic and energy.
Ecological
The emission of CO2 is lower than would be issued for
the same energy by combustion.


4.DISADVANTAGES
Letal emission, emission of sulfuric acid which is
detected by the smell of rotten eggs, which in large
quantities not smell, and it is letal.
Thermal pollution, is produced by pouring hot water
into rivers and streams and the generation of
greenhouse gases called.
In certain places, not all areas of the world have a
usable energy source, the temperature may not be
sufficient or quantities of water.
Cant carry, as primary energy.
Exhaustible.
Contamination of nearby waters with substances such
as arsenic, ammonia
Deteroration of the landscape, for the construction of
plants, soil excavations
Environmental impact.


5.WHERE THEY ARE
The principal geothermal plants are distributed
principally by the zone of
1. USA, Raft River: It was the first geothermal plant in
the world with binary cycle
2. ICELAND, Nesvavellir: It is one of the biggest
geothermal plant in the world.
3. RUSSIA, Mutnovski: It is the biggest in Russia, it
has more than 90 wells.

6.ENVIRONMENTAL IMPACT

It has bad environmental impact. It is cause by:
-Water Quality and Use
Geothermal power plants can have impacts on the
water quality and consumption,
Hot water pumped from underground reservoirs often
contains high levels of sulfur, salt, and other minerals.

Air Emissions
It is an open system and that suppose a problem
because it emit hydrogen sulfide, carbon dioxide and
others dangerous gases. Hydrogen sulfide is the most
common type of emission. In the atmosphere it
changes into sulfur dioxide which form small acid
particulates that can be absorbed by body and cause
diseases, sulfur dioxide also cause acid rain
This air emission cause too global warming, a problem
which all the world is involve to solve.
Land Use
The amount of land required for the installation of a
geothermal plant is too big, and it cause alterations in
the landscape.

7.COST
According to studies, an economically competitive
geothermal power plant can cost as low as $3400 per
kilowatt installed. The cost is high at firsty because the
initial construction costs of a geothermal facility
represent two thirds or more of total costs.
Geothermal power does not need outside fuel to
operate geothermal on a constant source of free fuel.
Factors:
Size of the plant
Power plant technology
Knowledge of the resource
Temperature of the resource
Chemistry of the geothermal water
Resource depth and permeability
Environmental policies
Tax incentives
Markets
Financing options and cost
Time delays






8.MISCELLANEOUS