Using geothermal water for greenhouse heating

On construction with dimensions 15 x 5 x 2 m, conditions of temperature transmission and vegetables growth are examined. We have been cultivating pepper, cucumber, small cucumber, tomato, and lettuce. Over ground heating has been used, consisting of one bent pipe with radius of 10 mm, in the shape of hairpin along the both sides of the construction. Underground heating consists of six pipes with radius of 20 mm on the depth of 350-400 mm. There have been measured the temperature inside construction, the temperature outside construction, the waterflow, and water temperature flowing into and out of the construction. The approximate heating flow factor K is determined by both the equation: heating balance equation and basic equation for temperature transmission. Vegetable growth has been watching during the period of time from March to November 2005.