Commercial cannabis cultivation load calculations.

[chazbolin]

With more states (21 to date) adopting medical cannabis laws that allow commercial cannabis cultivation it is clear that the loads these facilities require is far beyond what the typical interior space would require of an electrical distribution system. This paper was written in 2011 by Dr. Evan Mills an energy policy analyst at Lawrence Berkeley. What you will see is that even in 2011 he was factoring 200 watts/sq ft load calculations. Since then the commercial crop production managers have been considering even higher wattage systems such as dual ended 1000 watt HPS lamps that consume 1,150 watts and contribute <5000 btu/hr each to the rooms. But in the interest of developing natural sunlight conditions they are looking at adding another 300 watts of plasma to the HPS for to give the plants a UV-B range which the HPS lacks. This widening of the spectrum is known to improve flowering quality but will drive Dr. Mills 2011 calculations up to 250 watts/sq ft.

http://evan-mills.com/energy-associates/Indoor_files/Indoor-cannabis-energy-use.pdf

No matter what you may think personally about cannabis the fact is many states are adopting these laws because it generates taxable revenues. They are going to issue licenses to expand that income stream and more states will recognize the advantages of controlling this industry while reaping the financial gains. The problem is that utilities are going to reach their limits of providing service in the capacities these growers are demanding. The traditional energy savings incentives do not apply when you have cash crops that return $9K at the POS on a pound of product.

http://www.nytimes.com/2014/02/21/u...m-legal-marijuana-sales.html?hpw&rref=us&_r=0

As electrical professionals it is only a matter of time before this industry comes knocking at your door. At some level you will be asked to provide products or services that directly or tangentially involve this industry. If current political trends hold course there is going to be a demand for electrical distribution like I have never seen in 30 years in this industry. It will be up to us to provide intelligent systems and controls that employ tactics such as; incorporating lighting schedules that work with smart meters Time of Use metering to reduce Kw/hr rates, employ automatic demand response contracts on high wattage clients where a 50% reduction in lighting output for up to 3 hours does not jeopardize crop production, peak shaving, emergency back up generators, paralleling solar/wind/geothermal to offset utility consumption, smart technology lighting and controls that can meet a crops daily light integral, think of this as a task fc/lux level for plants that can be repeatably met without wasting energy unnecessarily as the plants become light saturated which wastes power once that condition has been met.

Lastly think of cannabis as just the tip of the indoor crop production iceberg. The projections brought forth to the traditional agriculture farming industries is that they are to be prepared for a doubling of the world population to 15 billion by 2050. I was at a rural land management expo late last year and this is now become a topic of hot discussion amongst these farmers as to just how they are going to meet these demands with even the most advanced energy and water savings farming techniques. The answer is they are not. To meet this demand it means that more of our food crops are going to have to come from indoor cultivation which is closer to the consumer, allows us to repurpose inner city buildings, train youth with agricentric skills, and deliver fresh, organically grown (non GMO) produce year round. All of these systems take power. Again it will be up to us to educate ourselves with both energy and water saving systems and procedures that can meet optimum crop production goals.

 

[jumper]

Folks, please stay on topic and keep the discussion electrical.

 

[K8MHZ]

I have wondered why there have not been many reports of fires. From pics I have seen, they stuff the lights in as close as possible.

So they have to run A/C. A walk through a 'grow store' will amaze you. In addition to lights and A/C, they also have humidifiers, fans, pumps for hydroponics, heaters, ionizers, air filters and the like all fighting for power.

Many people have these set ups in their homes. 1000's of watts of light and heat in a tiny, closed room just seems like an accident waiting to happen, to me.

I really don't think, as electricians, we should be in the business of designing MJ rooms any more than we need to know how to calculate the load needed to grow grapes indoors meant for champagne.

Here is another issue. If the MJ is medical MJ, where would a place to manufacture medicine fall under the NEC?

 

[kwired]

Lastly think of cannabis as just the tip of the indoor crop production iceberg. The projections brought forth to the traditional agriculture farming industries is that they are to be prepared for a doubling of the world population to 15 billion by 2050. I was at a rural land management expo late last year and this is now become a topic of hot discussion amongst these farmers as to just how they are going to meet these demands with even the most advanced energy and water savings farming techniques. The answer is they are not. To meet this demand it means that more of our food crops are going to have to come from indoor cultivation which is closer to the consumer, allows us to repurpose inner city buildings, train youth with agricentric skills, and deliver fresh, organically grown (non GMO) produce year round. All of these systems take power. Again it will be up to us to educate ourselves with both energy and water saving systems and procedures that can meet optimum crop production goals.

Indoor crops is not new, outdoor growing saves some cost, but not all areas have ideal growing conditions, at least not year round. There is a facility in my region that has been there for some time that grows tomatoes indoors year round. I have not seen it but have heard some details, they are not planted in dirt they are grown in a liquid solution (can't remember what they call that process of the top of my head), they have their own bee population for pollenation, the tomatoes are not necessarily the most appealing for use as whole fresh tomatoes in your local produce market, they are more for sending to other food companies for further processing in other foods. Even during growing season for outdoor plants in the region you still have benefit of protection from strong wind storms, hail, etc. that can devastate an outdoor crop, and could do so for the entire growing season if it happens at the right time.

Now the product in question here is going to be more profitable and will make more sense to invest in a growing facility as compared to other plants, so you likely will see more of these coming up - but supply and demand still rule the prices, if enough facilities are built, it will eventually drive the commodity price lower.

 

[GoldDigger]

Hydroponics.

Tapatalk!

 

[K8MHZ]

One thing to keep in mind is the voltage limitation on luminaires in dwellings.

210.6(A)

 

[mgookin]

I have wondered why there have not been many reports of fires. ...

I agree. And electrocutions. Around here the electric utility will blow them into the cops if the bill is out of range for the type structure so they jump ahead of the meter at the top of the weather head with romex. Another casualty of prohibition. At least making it legal will make it safer, and that's what we all want.

 

[chazbolin]

I really don't think, as electricians, we should be in the business of designing MJ rooms any more than we need to know how to calculate the load needed to grow grapes indoors meant for champagne.

Years ago I would have agreed with you but here's what's changed my mind. The vast majority of agronomic industry professionals know alot about their plants, any plants, environmental needs insofar as how much water, temps, nutrients etc., but since light is pure energy they have a hard time grappling with how much light and in what spectrums does it matter to meet successful, repeatable yields. Having done presentations with some of the leaders in this industry I can tell you that there is alot of general disinformation and even academic doctoral level research, that has not taken into account things like spectral shift in the lamps they are using. I won't get into the weeds (no pun intended) here with all of that but the reality most of these indoor crops lighting needs are based on more watts = greater yields regardless of what crop we're talking about.

As a contractor or engineer I start every project with a need to get a basic understanding of my clients operational needs so I can give them a safe, reliable electrical system that can serve them for many years to come. What I can tell you with complete certainty is that there are very few commercial crop production managers that have a grasp of the physics of lighting, the physics of plant lighting and of those few even fewer yet recognize how these systems they are designing will impact the electric utilities capabilities of meeting our regional and national demands as these industries continue to evolve.

Here is another issue. If the MJ is medical MJ, where would a place to manufacture medicine fall under the NEC?

Indoor grown food would have to meet USDA requirements for how that food is processed. Many states are dealing with indoor MMJ as a clean room pharmaceutical environment but what I've not seen yet is where the local electrical inspectors are treating the electrical installations as such. Typically a clean room is positively pressurized to prevent microbacterial ingress and that would include all conduit passages between the environments.

 

[K8MHZ]

I agree. And electrocutions. Around here the electric utility will blow them into the cops if the bill is out of range for the type structure so they jump ahead of the meter at the top of the weather head with romex. Another casualty of prohibition. At least making it legal will make it safer, and that's what we all want.

It's legal to grow here in Michigan if you have a card. Huge electric bills no longer 'tip off the cops'. A bill does not tell if a person can grow legally or not, and the State considers that information to be private.

People are putting in huge systems on their own and who knows what they are using to wire them up with.

 

[chazbolin]

Indoor crops is not new, outdoor growing saves some cost, but not all areas have ideal growing conditions, at least not year round. There is a facility in my region that has been there for some time that grows tomatoes indoors year round. I have not seen it but have heard some details, they are not planted in dirt they are grown in a liquid solution (can't remember what they call that process of the top of my head), they have their own bee population for pollenation, the tomatoes are not necessarily the most appealing for use as whole fresh tomatoes in your local produce market, they are more for sending to other food companies for further processing in other foods. Even during growing season for outdoor plants in the region you still have benefit of protection from strong wind storms, hail, etc. that can devastate an outdoor crop, and could do so for the entire growing season if it happens at the right time.

Good points all. But remember in my OP we are also talking about the need to expand food production closer to where the food is consumed. This is a reality and it really does not take government subsidies to do make this profitable. I have vertical hydroponics (soiless) systems that are stacked 6 high on industrial shelving where the Arugula sells for $15.00 per pound and harvest in 21 days. Hydroponic systems are the systems of choice for these indoor growers since the ROI can be achieved in less time with more harvests per year than conventional soil gardens. From our perspective these systems have pumps that can never go down for more than an hour or you will lose that crop. So any system I get involved with will specify an emergency generator and ATS for all critical circuits. As is our normal consultation at the design level we want to make certain that the loads are optimized so that the generator is sized right for those needs.

 

[chazbolin]

It's legal to grow here in Michigan if you have a card. Huge electric bills no longer 'tip off the cops'. A bill does not tell if a person can grow legally or not, and the State considers that information to be private.

People are putting in huge systems on their own and who knows what they are using to wire them up with.

The average residence in the US will consume ~11K kWh per day. Smart meters can detect unusually high consumption patterns and highly regimented timed cycles that will run between 2-3 weeks of 18 hours on 6 hours off during vegetative phases to 60 days of 12 on 12 off in flowering cycles. Those that think stealing power to hide their activities are finding out that the utilities recognize unidentified loads that are not being billed for. These thieves get in more trouble for stealing power than they do for growing weed. But I would not be so quick to qualify this utility information as private. At any time a government agency who wishes to peak into a utilities consumer base and find who might hypothetically be drawing above say 50K kWh per day in a 1000 sq ft residence they are free to do so.

As to the quality of the wiring you're right in that it is rare that the grower will make an attempt to maintain safe code compliant wiring standards. They are usually driven by profits and with no inspections the conditions are usually fires waiting to happen. What I would like to see happen is that home owners insurance policies would exclude coverage if a fire occurs as a result of illegal, uninspected, wiring be the cause of a fire. It's a safety issue that would limit the insurance companies exposure and might help in discouraging these practices.

 

[K8MHZ]

The average residence in the US will consume ~11K kWh per day. Smart meters can detect unusually high consumption patterns and highly regimented timed cycles that will run between 2-3 weeks of 18 hours on 6 hours off during vegetative phases to 60 days of 12 on 12 off in flowering cycles. Those that think stealing power to hide their activities are finding out that the utilities recognize unidentified loads that are not being billed for. These thieves get in more trouble for stealing power than they do for growing weed. But I would not be so quick to qualify this utility information as private. At any time a government agency who wishes to peak into a utilities consumer base and find who might hypothetically be drawing above say 50K kWh per day in a 1000 sq ft residence they are free to do so.

Stealing electricity is not an issue here. A while back a contractor got caught bypassing meters, modifying meters and all kinds of stuff costing the POCO thousands. Now the POCO is very paranoid about stealing electricity and since the big bust (which got a lot of press and named a lot of names) no one seems to do it any more.

I did not mean the utility info was private. The info about who has a legal MJ card is and the state won't turn the info over to anyone.

There are so many legal growing operations in my county that dozens of stores selling grow lights and accessories have cropped up, pun intended.

The POCOS are raking in the bucks and unless pressed, have no motivation to get involved in 'suspicious' electric bills as high bills are now very, very common.

 

[chazbolin]

There are so many legal growing operations in my county that dozens of stores selling grow lights and accessories have cropped up, pun intended

Curious if these legal grows are being inspected by the AHJ's whether it be commercial or residential?

 

[K8MHZ]

As to the quality of the wiring you're right in that it is rare that the grower will make an attempt to maintain safe code compliant wiring standards. They are usually driven by profits and with no inspections the conditions are usually fires waiting to happen. What I would like to see happen is that home owners insurance policies would exclude coverage if a fire occurs as a result of illegal, uninspected, wiring be the cause of a fire. It's a safety issue that would limit the insurance companies exposure and might help in discouraging these practices.

I would think they already do. But I haven't seen any test cases. I have never heard of an ins. co. backing out on a claim because of illegal wiring, no matter if it was for horticultural use or for running an A/C unit or a space heater.

If they clamp down on grow systems, to be fair they would have to do the same for any illegal, un-inspected wiring.

 

[K8MHZ]

Curious if these legal grows are being inspected by the AHJ's whether it be commercial or residential?

I know a couple inspectors and they haven't inspected any. I have never heard of one being inspected, either. It may happen, but probably 99 percent or more go without inspection.

 

[K8MHZ]

What about a fire hazard as a result of the plants growing so high the come in contact with the lamp?

How is that mitigated, especially for electricians?

 

[chazbolin]

I would think they already do. But I haven't seen any test cases. I have never heard of an ins. co. backing out on a claim because of illegal wiring, no matter if it was for horticultural use or for running an A/C unit or a space heater.

If they clamp down on grow systems, to be fair they would have to do the same for any illegal, un-inspected wiring.

Perhaps but if I'm a contractor I have no disincentive to not getting a permit on an A/C or space heater circuit. In fact in most places maintaining your contractors license requires you to permit the job. But if I'm a homeowner installing high wattage grow lights I'm probably a DIYer since I don't want anyone, even a contractor, knowing what I'm up to. It is for this reason if I were an insurance company I would consider the DIY indoor growers electrical work to be of greater risk to policy coverage.

 

[chazbolin]

Perhaps but if I'm a contractor I have no disincentive to not getting a permit on an A/C or space heater circuit. In fact in most places maintaining your contractors license requires you to permit the job. But if I'm a homeowner installing high wattage grow lights I'm probably a DIYer since I don't want anyone, even a contractor, knowing what I'm up to. It is for this reason if I were an insurance company I would consider the DIY indoor growers electrical work to be of greater risk to policy coverage.

The other side to consider is how property owners who rent their properties out are probably not aware their tenants are growing and taxing already outdated electrical systems. This is an electrical service that should have been updated years ago but the owner is not interested in spending the money. This service drop feeds five residences on one parcel. Main circuit protection has been tenant bypassed from nuisance tripping from 6K watts of grow lights. The line side of the meters are of course unfused anyway. This imbecilic grower is so caught up in making profits that he literally risks the lives of every tenant on this property.

If I were the property owner and I signed off on my property insurance acknowledging that if there should be a fire as a result of illegal wiring I would not be covered for loss it might make me pay more attention to what would likely be personal exposure should there be a fire and death relative to my 'maintenance' of the electrical systems and what loads my low income tenants were putting on this system.



As a contractor this is as bad as it gets. There is not much else we can do but walk away from this type project when an owner or tenant asks us to make a repair. I would not even work with the owner unless he agreed to upgrade all the wiring on the property. Of course he see's the price to do this type of upgrade and decides against it. Instead he paints everything and raises the rent. IMO exclusionary language in property insurance may be the only way to motivate these people.

 

[kwired]

Good points all. But remember in my OP we are also talking about the need to expand food production closer to where the food is consumed. This is a reality and it really does not take government subsidies to do make this profitable. I have vertical hydroponics (soiless) systems that are stacked 6 high on industrial shelving where the Arugula sells for $15.00 per pound and harvest in 21 days. Hydroponic systems are the systems of choice for these indoor growers since the ROI can be achieved in less time with more harvests per year than conventional soil gardens. From our perspective these systems have pumps that can never go down for more than an hour or you will lose that crop. So any system I get involved with will specify an emergency generator and ATS for all critical circuits. As is our normal consultation at the design level we want to make certain that the loads are optimized so that the generator is sized right for those needs.

As far as food production goes, livestock operations are really not that much different. The old days of a few dozen head of livestock in outdoor pens has diminished fairly dramatically, many are raised in indoor controlled environments, and ventilation is just as or even more important as if it is lost those animals will suffocate and be a loss even faster than the loss will occur with plants. I have a swine farrowing facility I do some work at, one farrowing room holds 24 sows, each has a litter typically of 10-14 pigs. Lose ventilation in one room and not know about it and you have 300+ dead pigs and 24 dead sows in much shorter time than you will lose any crop because you lost lighting. I don't know enough about hydroponic cultivation to say for certain how long a hydroponic pump could be down before you have total loss, I can see some loss being possible yet be able to recover, but livestock is generally a situation of total loss and is rarely a situation of partial loss if ventilation is compromised.

Curious if these legal grows are being inspected by the AHJ's whether it be commercial or residential?

Around here agricultural installations are exempt from inspection so they would not be inspected. Not saying that is altogether a good thing, as you will find some pretty questionable wiring at some of these installations. Some POCO are refusing to connect a new service if voltage is more than 150 volts to ground though if it does not have a permit which will result in having it inspected. But that doesn't stop shabby installs from happening after the initial installation and inspection either. It's not perfect but is a step in the right direction as far as safe installations goes.

Perhaps but if I'm a contractor I have no disincentive to not getting a permit on an A/C or space heater circuit. In fact in most places maintaining your contractors license requires you to permit the job. But if I'm a homeowner installing high wattage grow lights I'm probably a DIYer since I don't want anyone, even a contractor, knowing what I'm up to. It is for this reason if I were an insurance company I would consider the DIY indoor growers electrical work to be of greater risk to policy coverage.

The other side to consider is how property owners who rent their properties out are probably not aware their tenants are growing and taxing already outdated electrical systems. This is an electrical service that should have been updated years ago but the owner is not interested in spending the money. This service drop feeds five residences on one parcel. Main circuit protection has been tenant bypassed from nuisance tripping from 6K watts of grow lights. The line side of the meters are of course unfused anyway. This imbecilic grower is so caught up in making profits that he literally risks the lives of every tenant on this property.

If I were the property owner and I signed off on my property insurance acknowledging that if there should be a fire as a result of illegal wiring I would not be covered for loss it might make me pay more attention to what would likely be personal exposure should there be a fire and death relative to my 'maintenance' of the electrical systems and what loads my low income tenants were putting on this system.

View attachment 9830 View attachment 9831 View attachment 9832

As a contractor this is as bad as it gets. There is not much else we can do but walk away from this type project when an owner or tenant asks us to make a repair. I would not even work with the owner unless he agreed to upgrade all the wiring on the property. Of course he see's the price to do this type of upgrade and decides against it. Instead he paints everything and raises the rent. IMO exclusionary language in property insurance may be the only way to motivate these people.

If we are talking about people growing in their homes we are getting off topic IMO, this thread was intended to cover facilities that are legally designed and operated for legal agricultural purposes.

As far as an apartment owner and insurance - illegal growing by tenants - I think it is fair for insurance rates to be higher just because you don't know what a tenant may do, which does increase the risks. I don't think it is right to exclude coverage because the owner has no idea there is illegal activity going on at his property though. Now I have no problem with insurance refusing to cover an owner that is involved with the illegal activity, but not if a tenant is operating something without the owners involvement or consent - and that can even extend to activity that is legal, but owner doesn't know it is happening.

 

[chazbolin]

As far as food production goes, livestock operations are really not that much different. The old days of a few dozen head of livestock in outdoor pens has diminished fairly dramatically, many are raised in indoor controlled environments, and ventilation is just as or even more important as if it is lost those animals will suffocate and be a loss even faster than the loss will occur with plants. I have a swine farrowing facility I do some work at, one farrowing room holds 24 sows, each has a litter typically of 10-14 pigs. Lose ventilation in one room and not know about it and you have 300+ dead pigs and 24 dead sows in much shorter time than you will lose any crop because you lost lighting. I don't know enough about hydroponic cultivation to say for certain how long a hydroponic pump could be down before you have total loss, I can see some loss being possible yet be able to recover, but livestock is generally a situation of total loss and is rarely a situation of partial loss if ventilation is compromised.

In a commercial hydroponic system the plants will generally survive for up to 12 hours without having freshly oxygenated water flowing around the roots. But if the garden is aquaponics which means fish waste is all that the plants are getting for nutrition then the pumps can't go down for more than an hour or fish will start dying. These commercial aquaponic gardens are becoming very popular as the investors can harvest tilapia, blue gill, perch, bass, cray fish, etc. These can be large indoor projects that exceed 200K sq ft. Like your livestock operations, back up power generation for the critical pump circuits is considered crucial.

Around here agricultural installations are exempt from inspection so they would not be inspected. Not saying that is altogether a good thing, as you will find some pretty questionable wiring at some of these installations. Some POCO are refusing to connect a new service if voltage is more than 150 volts to ground though if it does not have a permit which will result in having it inspected. But that doesn't stop shabby installs from happening after the initial installation and inspection either. It's not perfect but is a step in the right direction as far as safe installations goes.

I had never heard that. Without any type of inspection being required I can just imagine some of the things you encounter as far as accidents and equipment failures go. Hopefully the utilities will remain an ally by requiring these installations be inspected, especially when it comes to meter sets where an AHJ inspection has not occurred.

If we are talking about people growing in their homes we are getting off topic IMO, this thread was intended to cover facilities that are legally designed and operated for legal agricultural purposes.

It is off topic to some extent but worth considering the situation as a whole. In Arizona, Prop 215 passed allowing a limited number of licenses for commercial propagation, cultivation and distribution of medical cannabis. Prop 215 makes it illegal to compete with any of the licensed centers by growing cannabis for personal use within a 25 mile radius of the licensed operation. If caught doing so the law deals with these people more severely then prepassage of 215. If other states adopt this approach there is likely to be more scab wiring as a means of avoiding detection. That's the only reason I see it as relative to what we may encounter (safety first) in the field in states where cannabis laws have been passed.

If there are any utility engineers on this forum I would be very interested in any research that you can provide which shows grid impact projections in those states where commercial cultivation has been granted. Has there been any coordination between lawmakers and the utilities as to how many of these licenses may be granted based on the 200 watts/sq ft metric that these facilities consume? I'm concerned that in the states rush to legalize and generate taxable revenues they may have not fully considered the impact the number of licenses relative to the total sq footage that these operations are going to have on overall utility service capabilities.