Keith’s Corner — “The Energy Challenge of Indoor Agriculture”

June 2017


Keith’s Corner —
“The Energy Challenge of Indoor Agriculture”

By Keith Coursin, President, Desert Aire

One of the most significant impacts of the rise in indoor agriculture has to be the increased demands placed on the energy industry. What role can HVAC equipment manufacturers play in ensuring these impacts are largely favorable?

Recently the consulting company EUCI organized an energy conference to encourage dialog, find answers and help develop best practices. The importance of the HVAC industry as a role player was front and center, and for good reasons.

Market-Driven Factors
The size of the indoor agriculture market is bigger than you may know.  According to industry studies the sales of all products in 2016 exceeded $20 billion for the U.S. market alone.  The number of actual indoor farms will soon exceed 40,000, with many of them currently less than 1,500 sq. ft. in size.  

But as technology improves the average size of these facilities is also increasing. Indoor farmers are expanding their operations to meet the growing demands created by the farm-to-table and local foods movements as well as the legalization of cannabis.  

The result of this increase in the number of farms and their average size are increased needs for resources, especially energy.

Energy Demand, Cannabis Cultivation and HVAC Equipment
Within the U.S. indoor agriculture industry the upsurge in cannabis cultivation is largely responsible for the increased needs for energy. Cultivating cannabis in grow room facilities is very energy intensive. These facilities require large amounts of energy for HVAC equipment and lighting systems.

At the EUCI-sponsored conference, The Cannabis Industry Energy Challenge, John Morris, a board member of the Resource Innovation Institute, identified key impacts cannabis grow rooms are having on the energy infrastructure of the U.S. economy.  

Mr. Morris ranked the sources of increased energy demand from grow rooms as HVAC equipment (46%), lights (33%), vehicles (12%) and other equipment (9%). Historical metrics included the following:

•    1% of the 2011 U.S. electrical load
•    2% of 2011 California electrical load
•    2% of 2016 Colorado electrical load
•    45% of Colorado load growth in 2016

An Increasing Load, Increasing Opportunities
Note the 45% load growth in Colorado during 2016. Colorado’s legalization of both medical and recreational cannabis serves as a benchmark of what can happen to energy usage. 

The city of Denver had established a goal of cutting fossil fuel consumption by 50% of 2012 levels. Significant progress was being made to achieve this goal until the legalization of cannabis was fully implemented in 2014 and more commercial grow rooms began production. All of the previous gains in fossil fuel consumption were reversed and a growth of power consumption was observed in 2016.  

As a point of reference the HVAC electrical load in an office building is estimated at 1 watt per square foot of space. This can increase to 30 to 60 watts per square foot in an indoor grow facility. 

Another key resource for indoor farming is water. The volume of water required is noteworthy, but not as significant as outdoor agriculture. For example a head of lettuce grown outdoors can require up to 30 gallons to reach maturity, compared to a head grown indoors needing only 0.3 gallons.

Representatives of electric utilities at the EUCI conference acknowledged that the growth in the number and size of indoor facilities (pun intended) represents a new load growth for them.  

They realize this can lead to increased revenues if they plan now to improve infrastructure and provide these new indoor farms with the large power feeds they require.

In addition, several representatives discussed the need to develop best practices and reward commercial producers with energy efficiency incentives.

Action By All
All of the partners in the indoor agriculture industry – owners, utilities, municipalities and suppliers – must start to benchmark energy usage. This will allow participants to create a common vocabulary, industry standards, best practices and generally accepted goals. 

This common framework in turn will help create a more advanced industry that can proudly point to the benefits of sustainable food supplies, life-enhancing medicinal uses, jobs that support families, and tax revenues. All accomplished with fewer negative impacts on power networks, water supplies and the environment.

Progress on the common framework is being made. The Western Cooling Efficiency Center in Davis, California, is developing an energy model to track the different energy flows of an indoor farming facility. 

At a facility level for example there are substantially different energy requirements during the lights on vs. the lights off modes of operation.  

This new method of looking at the resources required by indoor farms will eventually include the electrical, water and gas inputs of different types of facilities. 

Meanwhile there is currently no baseline metric of production output. Examples of these would include the weight of product per square foot, or weight per light; so introducing a productivity component is not yet possible. With the efforts of all the partners in the indoor agriculture industry, we will get there.

-- Keith Coursin

Photo: John Morris, founder and board secretary of The Resource Innovation Institute, leads a presentation at the EUCI-sponsored conference, The Cannabis Industry Energy Challenge. Mr. Morris discussed the lessons utilities learned as they helped growers navigate power delivery hook up processes.