At Surna, it’s always been our overarching intention to design HVACD systems for our clients that meet every goal of their cultivation business, not just some of them. Our years of experience have taught us that there are so many ways to approach climate control in cannabis cultivation facilities, and that there is never a “one size fits all” answer.

So often the design process for cultivation facilities starts with a product the engineer or head cultivator is familiar with, which is then stuffed into the mechanical design regardless of whether or not it’s a perfect fit for the business. This is really a backwards way of doing things. In reality, the process of determining what will work best in a cultivation facility means understanding not just the relevant facility construction details, but also the nitty gritty as it relates to cultivation operations and long-term business goals as well. 

This is where the design process should really start. Being armed with this information is what allows us to guide our clients to the best possible solutions for their business.

We came to understand this very early in our own business, and we think it’s what sets us apart so completely now. Our constant pursuit of perfection for our clients is what guided our evolution from equipment manufacturer to full scale HVACD solutions provider—starting with the deep understanding of the client’s business, then to design, provision of equipment, controls, start-up and dial-in.

Understanding how different technologies are best applied in various circumstances is what led us to pursue all different types of technologies that we can offer to our clients—some manufactured by Surna, and others manufactured by our partners in the industry.

In that pursuit, one of our primary focuses has been on ways to gain meaningful energy efficiency without compromising on environmental conditions or biosecurity, and without breaking the bank as it relates to capital expenditures. 

By now everyone understands how much energy cultivation facilities use, and how meaningful that is to operating expenses, so reductions in energy costs translate directly to profit for the cultivator. But that reduction in operating costs is useless if the client can’t afford the technology and can’t be applied at all if it means sacrificing yields or product quality.

Our deep expertise in the challenges of cultivation makes us uniquely qualified to evaluate technologies and their applications in cultivation environments. Sometimes that means looking at existing technologies applied in a different way, and sometimes that means an entirely new technology developed specifically for cultivators.

Our line of custom air handlers, which can be applied in either chilled water or DX (refrigerant based) applications, resulted from those efforts.

Surna’s New Custom Air Handlers

First, we focused on coil designs and fan speed management—customizing the air handler to the loads and parameters in the cultivation space it’s being designed for. And we perfected the sensible and latent (cooling and dehumidification) ratios accordingly. This ensures maximum efficiency with a minimum of waste, no matter what the design parameters. Then, we had to make it affordable. The term “custom” implies long lead times and high expense—but we’ve put in the work to make these units comparable in both cost and lead time to standard, off the shelf products.

Knowing our coil design is as efficient as possible, our next challenge was to identify options that could boost efficiency and performance even further. This led us to heat pipe, wrap around and flat plate pre-cooling options. These technologies have been utilized primarily in heavy commercial or industrial climate control applications for years. We’ve redesigned, reimagined and reapplied them for the exacting demands of cultivation environments. The result is high latent (dehumidification) capacity and extreme energy efficiency, without sacrificing precision, all at a reasonable cost.

Rain or shine, heat or cold, incorporating these technologies into our custom air handlers allows cultivators to take advantage of the physics of refrigeration systems to reduce the load on the mechanical HVACD system, which reduces operating costs and transfers directly to the bottom line. We can provide this option in either our chilled water or DX air handling systems, depending on which application is most appropriate for your facility.

Here’s How it Works

Refrigerant in mechanical HVACD systems must be compressed to create maximum heat exchange (which is the primary driver of energy consumption in any mechanical HVACD system). But refrigerant also migrates naturally to colder areas—meaning that uncompressed refrigerant will still move to the coldest part of its circuit, displacing what’s already there, and creating a recirculation effect. This allows for a measure of heat exchange without compression.

When this option is selected, Surna’s air handlers take advantage of this natural behavior by operating two cooling coils—one with standard, compressed refrigerant or chilled water, and one closed loop but without compression (the heat pipe or flat plate heat exchanger). The air from the cultivation space passes first over the cold side of the heat pipe and removes sensible heat, directly reducing the compression load associated with controlling temperature in the space.

Precooling the air also substantially increases the dehumidification capacity of the chilled water or DX coil. The resultant energy savings are twofold: the amount of compression required for sensible cooling is greatly reduced (meaning, fewer and smaller chillers and/or DX condensers), and the capacity of the coil for latent cooling (dehumidification) is greatly improved. Resultant increase in air handling costs to add this option is largely offset by the reduction in compressor requirements. The end result is dramatic energy savings and lower connected electrical load, all with maximum operational precision and at a reasonable cost.

Figure 1. The Surna Custom Air Handler with and without heat pipe. The air handler with heat pipe has increased moisture removal while reducing the load by almost 30%! The performance of the cooling coil assumes it is the same DX coil with a 42F suction temperature. This is a representative example from one facility and actual energy savings may vary from facility to facility.

We are so excited for the opportunity to bring this technology to our clients, and we’re so proud to continue pushing the envelope and delivering innovative products and designs to the industry. Our custom air handlers really live at the intersection of performance, cost and energy efficiency, and they should be on the list of options to consider in nearly any facility. If you’d like to learn more, or for any and all engineering related assistance you may need with your facility, contact us today.