If you are applying for a craft grow license in Illinois, you might have noticed there is very specific verbiage when it comes to the type of HVAC system that is to be implemented. If your canopy area is less than 6,000 square feet you are required to provide “high-efficiency ductless split HVAC units, or other more energy efficient equipment”. In the event your canopy area is 6,000 square feet or more the HVAC system “will be variable refrigerant flow HVAC units, or other more energy efficient equipment”. When specific verbiage like this is found, most license applicants will default to the prescribed system in order to make the application easier to fill out, but there are better, more efficient ways to cool and dehumidify your cultivation space than VRF/mini splits.
There is no disputing that VRF/mini split systems are energy efficient as standalone systems, when properly sized, and in the correct environment. These systems are designed for sensible heat ratios (SHR) of 0.80 to 0.90. This is indicative of office buildings, schools, and hotel rooms. Even in these applications, VRF/mini split systems need the help of a dedicated outside air unit to be able to handle the hot/humid air coming in from outdoors. This “decoupled system” adds complexity for the operator as they have to take care of two different equipment types, but it also degrades the efficiency of the system as a whole as these dedicated outdoor air systems represent a large percentage of the HVAC usage for the building.
Cultivation spaces, on the other hand, have SHRs between 0.50 and 0.60. That is a two to five times increase in the dehumidification capacity needed over the environment VRF/mini split systems were designed to operate in. To supplement the lack of latent capacity, standalone dehumidifiers must be added to the space. In this scenario the dehumidifiers reject their heat into the cultivation space, increasing the amount of cooling needed and, therefore, the size of the VRF/mini split system. This setup is wildly inefficient, not to mention costly to install and maintain. So what do we do?
The good news is that the state of Illinois allows cultivators to implement “other more energy efficient equipment”. In a perfect world this equipment would be purpose-built for the controlled environment agriculture industry; meaning it can handle the high dehumidification loads found without the use of energy inefficient supplemental dehumidifiers. If possible, this unit would be built with energy efficiency in mind, so you do not have to sacrifice your bottom line to grow quality crops. At Harvest Integrated we have created a unit with all these features to be used in Illinois in lieu of VRF/mini splits.
Our Harvest Air units are purpose-built to help cultivators grow as efficiently as possible. It all starts with the Harvest Wheel, a total energy wheel that uses the outdoor air to indirectly economize the cultivation space. This technology allows our units to use the outdoor air to cool and dry the space without introducing it inside. For every BTU of heat and moisture that is removed by the wheel, Harvest Air limits the amount of heat and moisture that needs to be removed by the variable speed compressors, thus reducing the overall energy needed to cool and dehumidify the cultivation space.
Initial energy analyses for Chicago show that the wheel by itself can handle 100% of the cooling and dehumidification needs of a cultivation space 45-50% of the year. The wheel will also do some, but not all, of the cooling and dehumidification 30-35% of the year. That is 75-80% of the year Harvest Air removes heat and moisture without the use of compressors, which translates to an estimated annual energy savings of 45% over a comparably sized, purpose-built HVAC system (such as VRF/mini splits with distributed dehumidifiers).
If you are submitting a craft grow application in Illinois, you do not have to go with VRF/mini splits because they are the baseline. There is another, more efficient option on the market that will allow you to keep your cultivation space at the right temperature and humidity, while using less energy than the baseline system. Contact us today to discuss your project and get help writing your application around Harvest Air equipment. Come see how we can help you grow more efficiently.