Learn the basics of microgrids and nanogrids and see how they’re being utilized for indoor agricultural facilities.|What are Microgrids and Nanogrids?|
The terms microgrid and nanogrid are often used interchangeably, but they are actually two different systems. Although microgrids and nanogrids serve the same purpose, there are a few key differences. Both use direct current instead of alternating current like the centralized electric grid does. Direct current transfers electricity through wires more efficiently than alternating current, but direct current doesn't travel as far, so it needs to be close to its energy source. DC electrical grids only became feasible recently because the DC model finally found its missing ingredient: smaller and more localized energy producers like solar and wind power.
Microgrids are localized groupings of energy sources that are also connected to the centralized electrical grid (Also called the macrogrid). A building on a microgrid can use solar panels and other renewable energy sources to offset their energy costs or eliminate their dependence on the primary grid entirely. A building can also put excess power generated from solar panels back into the primary grid so it isn't wasted and to prevent damaging the microgrid's electricity storage from overcharging. If the primary grid has an outage, buildings on a microgrid can keep the power on with the renewable energy collected locally and even plug in generators to put power into their local grid.
A nanogrid is essentially a smaller unit of a microgrid. A nanogrid is usually a single building or complex that uses their localized energy source to power their systems. The easiest way to think of all these different grids is to go by how far they reach: Macrogrid > Microgrid > Nanogrid.
|How Are Microgrids Used For The Cannabis Industry?|
Since cannabis can be such a fickle plant, many growers have moved to indoor growing facilities in order to better control their plants' environment. An indoor growing facility that's dependent on the macrogrid for power comes with problems that microgrid power has the potential to solve. For starters, indoor growing facilities consume a lot of power, and a large carbon footprint doesn't always agree with a cannabis industry that is generally environmentally conscious. According to a study cited by Fortune, as of 2012, the total energy cost for indoor cannabis facilities in the United States totaled $6 billion, roughly 1% of the total energy consumed nationwide. As more states legalize medical and recreational cannabis, this number will rise.
From a business standpoint, not having an independent power grid can leave a company financially vulnerable if electricity prices fluctuate heavily, and an extensive power outage can ruin entire crops. In recent years, battery technology has improved enough to allow larger growing facilities to operate on their nanogrids. One such successful operation is Mari's Garden in Hawaii, an aquaponic facility that combines hydroponically grown plants and fish farming.
Mari's Garden in Hawaii successfully integrated to a full nanogrid to offset Hawaii's rising energy costs. Image courtesy of Microgrid Knowledge.
Converting an entire growing facility to a solar-powered microgrid is costly and requires expertise to install. Fortunately, companies like Scale Microgrid Solutions have business models that are adapted to these challenges. Scale Microgrid, for example, makes and installs modular microgrid systems that allow growers to scale into microgrids gradually so they can upgrade as their budget allows. Transitioning an entire industry to microgrids with renewable energy will take years. Companies like Scale Microgrid hope to make this transition more accessible by lowering the initial costs and giving growers manageable scaling solutions.
Know of any interesting microgrid or nanogrid solutions? Feel free to share them in the comments?