II CIRCOLO DI BAGHERIA «G.CIRINCIONE» CLASSE V F A united Eco Journey through Europe to the Future - 2015
GEOTHERMAL ENERGY THE SUSTAINABLE DEVELOPMENT The current development model can satisfy all our needs, but it risks compromising the ability of future generations to satisfy their needs. This is demonstrated by: the increasing consumption of energy; many environmental (pollution, greenhouse depletion ...);
emergencies effect, ozone
the continuous increase of the gap between rich and poor countries. That is why today people are talking about of sustainable development, environmental sustainability.
Sustainable development provides for two things:
1) learn more about the world we live in and be aware that the quality of our life and that of all the other inhabitants of the planet depends on the energy that we can use and produce without damaging the environment; 2) be aware that you need to make clever use of renewable resources and then learn how to use energy and what the environment offers us without waste
Renewable sources The renewable sources can give the required energy to satisfy our needs without exhausting the environment. They are: • Sun • Water • Wind • Heat of theEarth • Biomass • Hydrogen
Il calore terrestre produce un’energia rinnovabile: L’Energia Geotermica
THE GEOTHERMAL ENERGY Geothermal energy is that one produced thanks to heat sources of geological origin located in the deepest layers of the earth crust, where the temperature becomes gradually higher by penetrating deep.
GEOTHERMAL POWER PLANTS Power stations that use this kind of energy are called GEOTHERMAL CENTRES. The systems directly exploit the energy from underground, through perforations in places of special interest or using natural phenomena of great conveying energy (geysers, boric acid fumaroles, volcanoes).
Geothermal power plants in the world Geothermal energy is the luck of Iceland, where 85% of homes are heated with this energy source. In Africa, Kenya and Ethiopia have built the installations for geothermal energy. In Italy the production of electricity from geothermal energy is highly concentrated in Tuscany (Pisa, Siena and Grosseto). The biggest geothermal complex is located on Monte Amiata in the municipality of Siena.
Lardarello Power station Lardarello (Pisa) power station dated well before the mid-nineteenth century. The vapors from the underground were a viable alternative to innovative industrial steam engines of the time, and had the advantage of not using expensive coal to power boilers. A benefit that was not lost to the early nineteenth century Tuscan entrepreneurs. A Tuscan tradition that comes down to our days, and that puts the Tuscany region at the top of the exploitation of renewable energy from geothermal. It is not a coincidence that in Lardarello there is a "MUSEUM DEDICATED TO STEAM".
The Systems These types of systems are used to produce heat or electricity. The heat of the subsoil, with temperatures above 140 째 C, makes a reserve of water evaporate, which passes through a system of steam turbine connected to a generator; the steam then condenses in special towers and comes back in the storage tank. Steam can be used for many purposes (greenhouse cultivation, spas, heating of buildings etc ...). The systems are located where there is a geothermal field.
Geothermic Field A geothermal field, suitable for such use, includes: • A persistent source of heat (eg: the magma) • An aquifer that is a permeable formation where water can infiltrate and move freely • An impermeable rock that prevents water from escaping and keeps it under pressure Usually rainwater recharge the aquifer, integrating the quantity of water taken from the man.
A bit of history The use of geothermal water is ancient and probably dates from the Upper Palaeolithic. However, its development in a more specifically healthcare originated in Japan and Italy about 2000 years ago. The Romans exploited geothermal energy to heat water and the environments of the baths. Only since the Renaissance, however, spa is treated in a scientific way. Energy uses of geothermal fluids are developed later than spas. Since the '20s, the geothermal activity spread to Japan, Iceland and Hungary, and then, from the 50's, in the rest of the world.