The RZTO system is based on the phenomenon that, at a depth of a few meters, soil maintains a relatively stable temperature that approximates the mean annual air temperature and is unaffected by daily or seasonal air temperature fluctuations. The underground temperature is always colder during the summer and hotter during the winter than the top soil temperature. Leveraging the principle of Ground Source Heat Exchange (GSHE), the company installs a closed-loop system of pipes, where the lower part is installed at the stable temperature depth, and the upper part in the target crop’s root zone. Water flowing through the lower pipes is charged by the soil’s stable temperature. The heated (or cooled) water is pumped through the pipes installed in the root zone, where the heat (or cold) is discharged. The system is able to heat the root zone during the winter and cool it during the summer (by up to 10° Celsius), maintaining the RZT at a relatively stable and favorable range throughout the year. The energy consumption of the GSHE system is for the water circulation pump only.
Problem addressed: Extreme heat and cold stress which can damage plants at the root zone.
Potential improvement: the technology helps protect crops by heating/cooling the root zone, increasing the profitability and the stability of the crop production.
Source: Roots – Sustainable Agricultural Technologies Ltd.