Growing cannabis is an expensive practice. Whether its soil, CO2, water, or light, growers will run into a litany of costs to get their business up and running. So, it makes sense that frugal cannabis cultivators would take whatever advantage they could to either lower their expenses or increase their yield. But, what if there was a way to do both? It may seem like a fantasy, but a quick history lesson will illuminate a little secret behind the Fohse method of decreasing costs and increasing yields.
When commercial cannabis lighting first premiered, it was as stripped down as you could get. Most growers used 1000-watt double-ended High-Pressure Sodium lamps, the same you’d find in a streetlight, that had two functions: on and off.
Later, as our understanding of cannabis grew, more features were added to improve the control of a light. Cannabis, as a light-hungry crop, can take vast amounts of photons without being destroyed, but it grows and blooms according to the natural, seasonal cycles of light. Lower light in the winter and higher more direct light in the summer would trigger certain responses in the plant that would move it from seed to stem to flower. Functions were added, like dials, that gave the ability to run the light at full power, or at 75%, 50%, etc., to help the light more closely imitate the cycles of the seasons… Unfortunately, there were a few drawbacks.
Sure you could increase an HPS light from low to full power, but running it that hot will come at the cost of its lifespan and your budget. An HPS light also emits an immense amount of heat that can damage plants if they’re too close. It can also raise the ambient room temperature, which might cause water to evaporate faster, another hit to the budget, or raise the cost of air conditioning, which will also affect growers’ bottom line.
When LEDs became a viable mode of plant lighting, the main draw was their ability to save energy. Early LEDs ran on relatively low power, around 650-700 watts total. While it was saving growers on their energy bill, it was also costing them in other areas of their operation. The decrease to power resulted in lower yields, even though it saved electricity because it was casting less light at too wide an angle, meaning the PPFD was low. To compensate, LED lights had to be kept super close to the canopy, and moved incrementally as the plant grew to maintain a perfect distance, an imperfect practice we refer to as “chasing canopy”.
Chasing canopy is expensive and laborious, as it requires someone to regularly re-rack a light as plant grows. Industries sprung up out of nowhere to tackle the problem, selling lift systems that raised the lights as the plants grew, which added expense to a process that was originally marketed as a money-saver. And then there was the same problem that HPS had, the lights had to be run at full power to get any benefit from them, meaning they burnt through their lifespan at an alarming rate (not to mention the hit to the fixtures’ efficiency by running them at full power).
The problem of getting high output while still saving energy had yet to be solved without the need to compromise. You either cut energy with an LED, at the cost of your yield, or you burnt through money with an HPS system in order to get more product. That was until Fohse debuted the A3i.
The A3i is a powerhouse of a light, running at 1500W, more energy than the majority of competing LED lights. Its release initially seemed counterintuitive. If the main draw was a smaller electricity bill, aren’t you sacrificing that efficiency by making a higher wattage LED? Not quite; it comes down to the relationship between power input, LED efficacy, and lensing
The A3i debuted with top-of-the-line lenses, so any photons that would escape on a traditional 180º LED light was redirected within a 90º-110º angle, increasing the total amount of photons reaching the plant canopy, a measurement we refer to as PPFD. But that wasn’t enough.
In order to compensate for the heat that came from running such a powerful light, Fohse included top of the line heat sinks that distributed the heat from the fixture evenly amongst an aluminum surface, lowering the ambient temperature of the light to 110Âş, no hotter than a luxurious bath, so that energy could be saved in maintaining the temperature of the grow space. The light also covered a larger area, up to 5.5-ft x 5.5-ft, meaningless lights were needed to cover the same area.
But really, it was the power ramping feature that saved growers the most. While the light could be run at 1500 watts, controls were added to allow it to be run at specific energy intervals, from 30%-100%. You could run the light at, say, 1000 watts, which is where other lights cap, but never be running the light at full power. This meant the A3i wouldn’t burn out as fast as a 1000 watt light would, even while running at the same power. A light running at, or close to, full power will never be running at full efficiency, so by increasing the wattage capabilities of the A3i, Fohse made a light that could match the power and output of the best in the market at an efficiency with which none could compete. In a lot of the grow rooms where it has been implemented, the A3i is usually run at around 50% – 60% output, right around where it’s most efficient. The more experienced growers tend to top out at around 80-85%, and we still have yet to see anyone push their plants to use 100% of the A3i’s power… but the potential is there.
The added ability to increase the light’s intensity is what we like to call power ramping. This feature allows for a light to incrementally grow in its output to match the plant’s needs at every growth stage, so growers no longer need to adjust their lights with an expensive lift system or repetitive and costly labor. With Fohse lighting, it’s our secret sauce. Growers can ramp their lights up past what standard LED and HPS lights can match, all without ever being at full power, meaning the lifespan of the light is extended, as is its efficiency. It’s one of the many reasons growers switch to a Fohse lighting system: it runs better, longer, and cheaper than anything else on the market.
