Geothermal Works

Those, who visit the northernmost capital of the world, notice immediately the absence of smoke and smog, which does not quite rime with the name of the town, Reykjavik, which means Smoky Bay”. The main reason for the clean air is the natural geothermal water, which is exploited for central heating, swimming pools etc. In the thirties, during cold and still winter days, the situation was totally different. Thick clouds of smoke sometimes made it impossible to see the nearest houses. In 1928 the first borehole was sunk in the Laundry Springs” area. These hot springs had been used by the housewives of Reykjavik for washing the laundry for decades. The drilling brought increased hot water to the surface (14 l/sec.). The water was pipelined over a distance of 2 miles to the Swimming hall, the primary and secondary school, the hospital and 60 dwellings in the vicinity. In 1933 the first boreholes were sunk in the Reykir area, about 11 miles from town. The procurement of hot water increased constantly and in 1939 the water from the Reykir area was pipelined to town and the project of connecting all its houses was commenced.

This project was fully realised by 1943 and the volume of the hot water supplies was about 200 l/sec at 80°C. The town grew steadily and the demand of hot water as well. This called for continued drilling and in 1955 the number of boreholes reached 72. In 1958 the municipality purchased the first big drill and between 40 and 50 holes were sunk, thereof 20 within the capital itself. The deepest one, almost two miles deep, has been plugged and is not exploited any more.

The Municipal Energy Authority exploits five areas to supply the capital area with sufficient volume of hot water, Nesjavellir, Mosfellssveit, the Laugavegur area (in town), the Ellida river valley area (in town), and the Hellisheidi area. The distribution system is designed for a peak demand at -10°C. When the peaks rise higher, reserves from 13 tanks (64.000 tons) are available and more supplies are heated with oil. The deuterium contents of the water make it possible for the scientist to determine the origins of the water above sea level, because they increase with height. The tritium contents, however, only shows that the hot water fell in the form of precipitation after 1952. Tritium less water dates back to the time prior to the explosion of the first hydrogen bomb, as is experienced with the boreholes inside the capital area itself. The borehole pumps are located at a depth of 110 – 170 m.

The main pumps forward the water to the distribution centres of the town quarters, where the third set of pumps complete the delivery. Considerable energy is still left in the 25 – 30°C hot outlet water from the houses and it is used for the heating of winter gardens, green houses, hot pots, parking areas, pavements and streets, if it does not flow directly into the sea.