How Solar-Panels Could Revolutionise Grow Rooms

Indoor growing is energy intensive business. Even more so if you consider the fact that approximately 1% of total US electricity goes into cultivating indoor grown plants. It’s quite a fact. It’s also estimated the number will grow to 3% by 2035. All of the equipment used to produce high quality buds consumes 13,000 kWh of electricity per year in a 3.5m3 space of a grow room. Also, that same equipment that’s kept on for huge lengths of time to keep the plants alive and happy produces a lot of CO2. To put it in perspective, growing one kilo of bud will produce 4.3 tons of carbon dioxide. The impact on the ozone layer made by indoor growing could not have really been measured until now, due to the secrecy involved in the growing process. However, as marijuana laws reforms sweep the globe and numbers start to slowly roll in, it gets very easy to tell that growing indoor is not an eco-friendly business.

Luckily there are a couple of ways to solve the said problems. One is to move the crops outside. Go back to the roots. Let the sun take care of the lighting and the wind can be the air conditioning. Sadly, for many, this is not an option. With many countries who have yet to consider jumping on the legalization bandwagon, issues like hiding the crops remain for the grower. The other solution to the problem also relies on the sun, but in a different manner. We are, of course, talking about solar panels.

Experimenting with setups

Solar powered grow rooms are not anything new. The problem with such grow rooms has been cost efficiency, but as solar panels become cheaper and more energy efficient, that problem is slowly becoming a non-issue. Another factor to solar powered grow rooms not catching wind is the growers’ unfamiliarity with such a setup. Using tried and true methods is what any one person serious about growing will rather go for, than experimenting with setups on which information is admittedly scarce. It is true there is little room for experimentation for an average grower, since failure could result in crop losses and consequently financial losses.

Over the past 8 years the production of renewable energy sources has really taken off, largely due to high production levels in China. At the same time, technological advances have been steadily making renewable energy sources more viable in yet more scenarios. But because of the way solar energy works, powering the usual sodium pressure lights utilized in grow rooms could provide a bit of a problem. It would require a lot of power storage. Which means tons of batteries which need space to be kept in. Switching to LEDs or CFLs would relieve a lot of this hassle, but what self-respecting grower is willing to switch to LEDs or CFLs overnight? Now, crafting a hybrid setup – one utilizing both the grid and solar – is an excellent solution for this problem, retaining a lot of benefits that come with renewable energy. The electrical bill would still definitely plummet.

For those not wanting to settle for less than a fully solar powered grow room, there is still hope, thanks to innovation in the field of electricity storage. Today there are batteries that provide as much as 10kWh and can be charged by renewable energy sources. They can also be charged using electricity from the house during cheap hours, to use during high demand hours, so it could be utilized in the hybrid setup too. The battery can be chained in sets of up to nine units for extra kick, which could probably fly a Boeing for 2 hours, but… don’t quote us on that. A good example of quality, high-end solar battery would be Tesla, an invention introduced about year ago to the market.

The payoff

Going full green on the growing operation is not a cheap decision. You can imagine a 10kWh battery produced by Tesla isn’t cheap and isn’t sold at your nearby utilities store, while solar panels can still burn a hole in your pocket too, but prices may vary depending on the country. If we assume that we need 2kW for our 0.6 by 0.6 meters of grow room, and the panels cost an average of $7 per Watt, that’s $14,000. The price goes higher as the room gets bigger. The Tesla battery sells for around $3,500, and buying just one will not cut it. But one important thing should be pointed out here: this is a onetime cost. Once the panels are laid down, they start paying for themselves. There is no maintenance cost (apart from an occasional window cleaner and cleaner solution) and the panels don’t need to be changed. A small percentage of efficiency drop is expected per year, but at 0.5% it’s fairly negligible, especially since after 25 years of using the photovoltaics it gets to a steady 80% of original efficiency. The weird thing about this is that some panels even outperformed their original factory specifications after that period. The batteries however, will need to be changed as their capacity keeps degrading from day one, not linearly of course, but after 5 years the decrease in capacity gets more and more noticeable. While this money might seem steep enough to bail on this idea, keep in mind that the electricity costs can reach these sums in just a couple of years, again depending on the size of the operation.

Taking the costs to setup such an operation into account, the return on this investment could range from 3 to 4 years, and as time goes on, and more and more advances in the field emerge, that time keeps shortening. Imagine not having to worry about the electricity bill; not needing an extra generator to make up for the high drain to avoid suspicion. Also, imagine not having to worry about carbon footprint of your joint. All things considered, going head first into creating a fully self-sustainable grow room requires meticulous planning and logistics, and definitely some meticulous cash to start off. Growers who already have a setup that works for them which does not utilize any renewable energy sources, would probably be better off easing into the scheme, as going off grid cold turkey could prove a very stressful endeavor, especially for bigger operations. But for growers designing a new setup, including solar panels in it is something that should definitely be taken into consideration, because let’s face it: self-sustainable grow rooms are definitely the future of indoor pot-farming.

Steven Voser

Steven Voser is an independent cannabis journalist with over 6 years of experience writing about all things weed; how to grow it, how best to enjoy it, and the booming industry and murky legal landscape surrounding it.

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