The systems is able to maintain an optimum range of temperatures (usually between 16-28 Degrees celsius ) year round regardless of air temperatures.
Benefits:
• Dramatically reduce energy costs and environmental pollution. Optimal RZTO minimizes the need for heating/cooling the plants themselves significantly. Thus, growers can lower (or increase) the thermostats on their air heating/cooling systems if they incorporate Roots’ systems.
• Increased yield. Our field test results and commercial installations feedback point to a pattern of yield increase 20% to 250% compared between un-cooled and un-heated crops.
• Superior crop quality: The results indicate that the fruits and vegetables grown with RZTO tend to be larger, tastier, and mature earlier than the control groups.
• Faster time to market: To date, field tests conducted with lettuce, leafy vegetables, herbs, and flowers resulted in a significant shortening of the growing cycle, thus achieving excellent prices.
• Planting off-season: Due to our smart root cooling system, we
successfully planted flowers in hot climate areas earlier or plant earlier after the winder due to substrate heating.
• Irrigation savings: Enhanced moisture retention in the soil in cooled beds during the summer reduces irrigation rates.
• Reduction in the use of Pesticides – keeping the plant’s root zone temperature in an optimal range helps the plant resist infestation and improves the plant’s immune system; thus the need for expensive and environmentally damaging pesticides can be reduced.
There are four configurations:
Heat Pumps (either electric or gas) coupled with a monitoring and control system and water tank. The system cools or heats water in a tank, and the water is circulated in a closed cycle in pipes and through a T shaped heat exchange probe placed in any substrate. This provides the most accurate range of root zone temperatures year round.
Ground Source Heat Exchange (GSHE), where ROOTS installs a closed-loop system of pipes, in which the lower part is installed at the stable temperature depth, and the upper part whithin 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 whithin the root zone, where the heat (or cold) is discharged. The system is able to heat the root zone during winter and cool it during 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 the result of the water circulation pump only.
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A hybrid system of heat pumps and GSHE coils.
A combination of heat pumps with a drip irrigation/fertilization system in one piping system. The combined system utilizes variable pressure to use the closed cycle to either heat or cool the root zone area and an open cycle with tap water and a fertilization tank, to irrigate the crops with drip irrigation. This saves the need to buy and install two separate systems.
Heat pumps have higher energy consumption compared to GSHE, (still providing 80% saving vs. air heating and cooling) but they can be programmed to provide a very accurate root zone temperature range as needed. Heat pumps work only when the root zone area exeeds a pre-determined range.
It is also possible to install a hybrid system that incorporates both GSHE and a heat pump. In this configuration, the heat pump is used only during extreme heat or cold spells adding extra cold or heat on top of the water temperatures existing in the GSHE. Thus the overall energy consumption of the hybrid system is relatively small. The GSHE system, relying on free underground heat exchange between the soil and the water circulating in the coils, consumes the least amount of energy as it relies only on a water circulation pump for its operation.
