GEOTHERMAL ENERGY FOR GREENHOUSE HEATING AT ASTEN
Desde 1988-01-01
hasta 1989-06-01
Detalles del proyecto
Coste total:
EUR 638 248
Aportación de la UE:
EUR 255 299
Coordinado en:
Netherlands
Régimen de financiación:
DEM - Demonstration contracts
Objetivo
To extract geothermal water from the Dongen sand at Asten, South East Netherlands for existing greenhouse heating. The extensive exploration programme carried out in November 1986 and March 1987 with DG XII support (EN 36/A - 1/140/NL) has given the following results : The geothermal aquifer potential would reach 120 m3/h at 60 deg. C of highly saline water.
Geothermal energy will cover about 80 % of heating requirements and an existing natural gas installation will be used as back up. Reinjection well is required because of the high salinity and to maintain the reservoir pressure. Annual energy saving amounts 1500 TOE and calculated payback is 10-12 years.
The test well has demonstrated that geological inventory studies should be used with great care in estimating geothermal reserves. Only one of the four potential reservoirs (Breda formation) is exploitable. The seemingly most promising aquifer, the Berg Sand, could not be identified as such on the basis of the geological data available. The technical feasibility of geothermal power recovery can be studied by completion of a geothermal doublet.
The economic study showed that, under current conditions, geothermal energy recovery from the Breda formation with the use of heat pumps and/or a cogeneration set is economically feasible with a natural gas price of approximately 0.15 to 0.26 ECU/Nm3 in commercial greenhouses with a minimum area of 20 ha.
The implementation of the exploration well and the research of the reservoir characteristics took place over two periods. Between November 1986 and March 1987 the test drilling and planned research programme was carried out. This included an airlift test and a test drilling to the deepest formation at Houthem - 1636 to 1656 m. To verify the first favourable results obtained in the Berg Sand, 1494 - 1513 m, a production test was done between March and May 1988, using a nitrogen lift. The Berg Sand can supply hot water at a temperature of approximately 60 deg.C. However the formation water flow of this sandy aquifer is only 45 m3/h at an average productivity index of 2.5 m3/h/bar and a delivery height from the submerged pump of 18 bars. This formation could only be exploited by means of a doublet due to the high salinity of the water which is up to 51 g/l.
The Breda formation can supply a geothermal water flow rate of 234 m3/h at a productivity index of 13 m3/h/bar with a correlative drawdown of 170 m. However the temperature of the formation water is only 35 deg.C. This formation could be considered as a good geothermal reservoir but its low temperature prevents its exploitation without additional facilities, in particular a heat pump.
Coordinador
JAMES WATTSTRAAT 79, BOX 4129
1009 Amsterdam
Netherlands
See on mapContacto administrativo: VIERHOUT R. M.
Tel.: +31-20598111