Altheim is a city with about 5.000 inhabitants in the province of Upper Austria. 
It is located about 60 km north of Salzburg and about 15 km from the German border 
(Bavaria). Geothermal energy for district heating has been used since 1990. The 
capacity is more than 11 MWth. The ORC project started in 1996 (proposal to the 
European Commission). District heating and power production is operated by the 
city itself within the city's budget.

ORC project:
- Commissioned end of 2000

- Design data/nominal conditions:
  Hot water flow rate: 81,7 kg/s
  Hot water temperature in/out: 106°C/70°C
  Cooling water flow rate: 340 kg/s
  Cooling water temperature in/out: 10°C/18°C
  Electric net output: 1 MW

- Experiencies:
  In general: There is a big difference between nominal conditions and the
               real world.

  The earth is reliable. No problems concerning hot water temperature and hot water
  pressure.

- Main problems:

  Control system:
  District heating has priority - hence only the quantity of hot water which is not
  needed for that is available for electricity generation

  Cooling water side:
  That means cooling water quantity, cooling water purity, cooling water temperature

  Working fluid side:
  In 2005 the working fluid had to be replaced (the plants efficiency increased)

- The availability of the plant is very high - up to more than 7.500 hours/y

5, rue des Moulins
67000 Strasbourg