Piancastagnaio Project - Bellavista, Italy

The project started in 1984 with the target to find the steam necessary to feed 7 new power plants of a standard size of 20MW. The drilling of 47 wells in an area of about 27 Km2 was planned. The project supplies the national grid with additional energy and gives an impulse to local trade and enterprises.

ftp://erg.ucd.ie/public/pdfiles/res/case_studies/gt_01.pdf

GEOTHERMIE Ding scheme, Southampton, UK

The district heating scheme in Southampton closely resembles a huge domestic central heating system. Hot, treated water circulates underground from the heat station to customers in the city centre and it is then returned for re-heating. A closed loop of high-tech pipes distributes heat from all Southampton's energy sources around the city centre.

It is now clearly apparent that co-operation was a main factor which contributed to the success of the Southampton scheme. Co-operation between the public and private sector, between the City council and its development partner Utilicom and co-operation with the European Union and the U.K. Department of Energy.

http://www.energie-cites.org/BD/PDF/sou003en.pdf

Geothermal Plant in PRENZLAU, Germany

The installation in the town of Prenzlau - which was built when this was still the German Democratic Republic, and was re-activated in 1995 - was the first one in the world to extract heat from the Earth's interior by means of a 2.9 km deep drilling hole, without mass transfer.

The plant was constructed by carefully planned conversion of existing production facilities, and by building new ones.

Completed, it comprises:

• 3 oil or gas-fired hot-water boilers (two 4.1-MW boilers, and one with 1 MW capacity)



• A geothermal plant consisting of: a plate heat exchanger (150 kW) for direct heat exchange and a heat pump (350-500 kW) for extracting heat from the bore water

http://www.energie-cites.org/BD/PDF/pre-geo-en.pdf

Geothermal Project at the Air Force Hospital in Lisbon, Portugal

This is the first geothermal direct heat utilization project in the Lisbon Sedimentary Basin and is located at the Air Force Hospital in Lisbon. The project was developed by the Portuguese Air Force which is the owner of the installation and A. Cavaco which carried out the feasibility study, drilling operations, design and installation of the geothermal station.

The objective of the project was to provide the town of Ferrara with a station and a network for district heating and sanitary water using geothermal water and domestic wastes as heat source. 200 m3/hour of water at 98°C are pumped from the geothermal well (Casaglia 1) and are reinjected into the depth well (Casaglia 2) after the primary heating exchange. The contribution of the geothermal energy was 63%. The heat in cascade (from 40 to 60) is used for greenhouses, fish farming and drying processes.

ftp://erg.ucd.ie/public/pdfiles/res/case_studies/gt_03.pdf

Economy & investments at the Nesjavellir power plant, Iceland

Hitaveita Reykjavikur has financed the whole project from its own funds without any borrowing.

If one assumes that the first phase of the power plant will be operated for the base load with an annual operation of 8000 h, real interest rate of 7%, depreciation period of 25 years, annual operation costs of 2% of the capital investment and interest on capital during the construction period included, then the energy price from the phase 1 of the power plant at Nesjavellir will be 0.014 US$/kWh delivered to the storage tanks at Grafarholt.

http://www.energy.rochester.edu/is/reyk/economy.htm

Geothermal Rankine Cycle Plant Generates Electricity

Hot water from a geothermal source is now used in Altheim, Upper Austria not only to supply heat to the district-heating network but also to drive an Organic Rankine Cycle (ORC) turbine to produce electricity. The cooled thermal water leaving the ORC is re-injected into a new well to preserve the aquifer.

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