Plants for the Distributed Generation: geothermal systems

Printer-friendly versionInvia a un amico
geothermal plant
by Maria Rosaria Barbato

Our planet produces a continuous flow of heat to the surface layer. From a depth of about 20 meters, the temperature increases by about three degrees Celsius for every 100 m depth; in certain areas, called geothermal areas, this change is much more rapid and, just 6-7 kilometers deep, temperatures of 200 ° C can also be reached. 

In 1905, with the construction of the first geothermal power plant in Larderello in Tuscany, Italy was the first country to exploit the great potential of this renewable source; in fact, on the Italian territory, the areas with the greatest potential for geothermal energy are four: 

- The first one is Tuscany, with its geothermal fields of Larderello,  the Bolsena caldera and the sea, for several miles; 

- The second one is Campi Flegrei, in Campania; 

- The third, very large (and still little-known) geothermal area is  the southern Tyrrhenian Sea; 

- The fourth is the channel of Sicily, in the submerged area of volcano Empedocles and Lampedusa. 



A geothermal system converts the heat of geothermal fluid, which is produced by the contact of the water with layers of hot rocks, into electrical energy. This may possibly be combined with the production of house heating (cogeneration). 

A geothermal power plant consists of a system of collection, treatment and conveyance of geothermal fluid up to the power plant: here the thermal energy is converted into electrical energy, while the steam is sent to a treatment system . 

Geothermal can be used at "high temperature", in hot water and temperatures above 150 ° C, or, as is widely spreading in recent years, at "average enthalpy", using the terrestrial heat present in the most superficial layers of the earth crust, with lower temperatures. 

In the high-temperature geothermal systems there may be either an ascent of dry and superheated steam (vapor-dominated system) ar an ascent of liquid water mixed with steam (water-dominated systems). The vapor-dominated systems are the rarest but, at the same time, they are also the most efficient, since, in the dominant water system, the liquid phase must be separated from the steam thus resulting in a greater energy consumption. 

The vapor is drawn through wells and piping systems and then it is used to activate the turbines that produce electricity. 

Besides the production of electricity, in the medium-enthalpy plants, the heat extracted can be directly used for the production of useful thermal energy, to fuel heating systems for buildings, greenhouses, industrial processes and etc.. 

Because of the lower temperature, the energy production of a plant that uses the average enthalpy can not be compared to that of a high enthalpy plant, but it can still meet the request of a few thousand households and it shows, due the several average temperature anomalies detectable on the territory, further development perspectives, both from an energy point of view and for the environmental and economic impact. 

At temperatures below 90 ° C, a plant is said to work at "low enthalpy" and, in this case, the production of energy is used for heating and cooling of buildings and in the production of sanitary hot water for residential or industrial use.



The warmth of the subsoil is exploited through the installation of geothermal probes coupled to geothermal heat pumps, the latter allowing the exchange of heat between the ground and the area to be heated. 

The low-enthalpy systems can be divided into closed-loop systems, which draw heat from the earth through a heat transfer fluid circulation, and the open-circuit systems, which are based on the sampling and subsequent return of water (groundwater, river or lake); the two systems exploit the same principle of operation.

The system uses a temperature of about 10-15 ° C, detectable at a depth of about 100 m from the earth's surface. Through a heat pump, the heat withdrawn from the soil is brought to a temperature suitable to power the heating system of the building and supply warm air in winter and cool air in the summer period. 
Despite the use of the heat pump, which requires a power supply, the use of a low-enthalpy geothermal system can be convenient: with a consumption of 1kWh, needed to operate the heat pump, 4 kWh of thermal energy can be produced, with 3kWh taken from the soil.


We recommend this headset without plug ears, even more cool is that it uses your Red Bottom Shoes bones as a medium,UGG Boots Outlet it sounds cool! The liberation of the ears can also be avoided due to the ears are plugged due to traffic accidents UGG Outlet so that there Coach Outlet is no safety risk while North Face Outlet walking and listening to music.Kenzo It is a headphone,Oakley Outlet but its shape is a hat,Christian Louboutin Shoes but ZEROi is Moncler Jackets a magical hat that looks the same as an ordinary baseball cap,Burberry Outlet but the biggest feature is the use of Red Bottom Shoes bone-conduction soundtracks.
Tokyo Design Polo Outlet Week as the first Coach Outlet release of exhibits,Nike Air Max Pas Cher after two years of discussion, is now finally completed the formal commercialization. Prior to this only for Coach Outlet Store Online the legal person to provide the purchase permission,North Face Outlet the address is limited to Namibian,Isabel Marant Chiba Prefecture, Namibian companies hold the land. However, starting from November 3,Nike Air Presto MUJI's hut will be for sale to North Face Outlet ordinary consumers, and the location of the hutAir Jordan Pas Cher will be expanded to Tokyo in the Kanto region and nearby eight counties and districts, Ray Ban Sunglasses and the company continues to True Religion Outlet look for more ways to The North Face Jackets continue Construction of cottage land.Air Max 90 Not unlike the style of Kate Spade a house or a villa,Isabel Marant Shoes the No-lodge is in a different mood than the hotel Adidas Yeezy it was when it was on the move. It was just a reassuring home for a young Nike chaussures pas cher Japanese who rented homes for thousands of people. Asics Shoes Muji Officials explained,Coach Outlet Do not look at Bape Hoodie it the smallest of only about 9 square meters,Cheap Jordans but because of the use of the design of Coach Outlet the type of building,Philipp Plein even if three people in the house at the same time will not feel narrow.Louis Vuitton Outlet In addition,Swarovski Bracelet Indigo products have always been simple style,North Face Jackets indoor ground with cement, 100% of the other Burberry Scarf places using native wood,Coach Outlet the walls without Coach Purses any decoration,Adidas Outlet intended to Kate Spade Outlet give consumers a DIY space.Scarpe Nike Air Max Different styles of huts Louis Vuitton Outlet also prepared Different thermal and interior options.
This is also in Coach outlet line with the needs Christian Louboutin Shoes of current consumers.UGG Outlets Nowadays,Ray Ban Outlet young Japanese people think daily about being Sac Louis Vuitton really happy Burberry Outlet even when living in an apartment.Coach Factory Outlet They have to Adidas NMD constantly Christian Louboutin Outlet move for rent or have to resort to Kate Spade Outlet work transfer Yeezy Boost 350 v2 Re-investing Nike Hoodies energy to find Coach Outlet Online a home is a stressful life style for them, and it is also an urgent need to be addressed in the market.
People talk about the Kate Spade Outlet time of the Scarpe Nike Air Max Uomo island is static,Acheter Philipp Plein which is North Face Jackets relative to New Jordans their mood in the city under the tyranny of time. Nike Air Max Shoes In the city,Coach Outlet Online the easiest way to keep your time Coach Outlet anywhere is to install clocks Red Bottom Shoes and watches in public places,Red Bottom Shoes with the Tory Burch Outlet clocks staring North Face Outlet at the town from squares, schools,Burberry Outlet train stations and more.Scarpe Sportive Nike Air Max 2017 Even when it is quiet, people can notice the Louboutin Pas Cher passage of time.Red Bottom Shoes The Maldives has Ray Ban Sunglasses a huge advantage Nike Roshe Run Pas Cher throughout the Indian Ocean and the Pacific Ocean,True Religion with high-quality sandy beach islands that can be reached in less than eight hours by Nike Air Max direct flight; comparable to Bali in Indonesia,Kate Spade Outlet but not only Guess Outlet with two different locations Island experience.North Face Outlet Bali is Michael Kors Handbags becoming Bali.The North Face Outlet Raffaele,G Star managing director Yeezy Boost 350 of the Grand Park Adidas Original Maldives hotel,Michael Kors said he had worked in Bali for a few years and witnessed Nike Air Max a shift from a modest island to Kate Spade Outlet a small business town.North Face Outlet There was an expressway Nike Air Max Pas Cher there but traffic jams were still there.Cheap NBA Jerseys Mauritius and Seychelles, the other two island Red Bottom Shoes countries in the Indian Ocean,Adidas Yeezy Boost 350 have more than 12 hours flight time.

Nice post

Very informative article about geothermal  systems, i like reading the content you have posted. I must say you have work hard in collecting data to write this post.

rubber sheet in elegant designs


Free Online Chat rooms are a great souce of entertainment where girls and boys can do friendship in a chat room with each other. Chat Rooms

Geothermal acitvity is

Geothermal acitvity is growing from year to year. Some of specialists thinks than Yellowstone would blow! rushessay dissertation has it's own version.

All rights reserved © - Copyright 2011 - 2014 - by enmoveme