Geothermal Greenhouse

Why Choose a Geothermal Soilless Greenhouse?

In modern greenhouses where soilless cultivation is practiced, year-round production is possible when the plant's needs for heating, lighting, ventilation, and carbon dioxide are adequately met. However, heating remains the most significant cost factor and often acts as a limiting element. While fossil fuels (such as fuel oil, LPG, coal, natural gas, etc.) are commonly used as energy sources for greenhouse heating, renewable energy sources (such as solar energy, geothermal energy, biomass, etc.) are also increasingly utilized. Among fossil fuels, high-quality coal may be economical, but in regions with access to geothermal hot water resources, heating costs can be even lower.

Using geothermal energy in agricultural production not only provides the required temperature for plant growth but also allows uninterrupted year-round cultivation—except in extremely hot periods. In greenhouses where heating is consistently maintained, not only is product quality improved, but the risk of disease is also significantly minimized.

How Is a Geothermal Soilless Greenhouse Built?

Hot water from geothermal wells (typically at temperatures of 75–80°C) is mixed and circulated into the greenhouse system. On warmer days, the temperature of the water supplied to the greenhouse is reduced, and ventilation is increased. Ventilation also enables carbon dioxide—vital for plant growth—to enter the greenhouse.

For heating, insulated steel pipes are installed within the greenhouse. The highest demand for heating typically occurs during winter, when average temperatures are at their lowest. While some greenhouses are equipped with thermometers, the heating system is not directly controlled by thermometer readings. The goal is not merely to protect plants from frost but to maintain the optimal temperature required for continuous plant development.

In contrast, most greenhouses in Türkiye are heated primarily to prevent frost damage rather than to maintain ideal growing temperatures. This is largely due to the high cost of heating. However, several consecutive days of temperatures remaining below 10–12°C can negatively impact both yield and product quality.