SUNK GREENHOUSE Russian patent published in 1999 - IPC

FIELD: agriculture, in particular, greenhouse for growing of seedlings and vegetables. SUBSTANCE: sunk greenhouse has light-transmitting covering and soil heating system with hollow perforated metal rods buried into soil and rigidly connected to heat conducting grid. Metal rods are attached to heat conducting grid with their portion bellow upper end projecting above soil surface. Perforated portion of rods is positioned below zone of attachment to heat conducting grid. EFFECT: increased efficiency by effective heating of soil layer due to complete employment of natural heat source energy and simplified construction. 2 cl, 1 dwg