Investing in LED grow lights is bound to pay off over time due to the lights’ low energy consumption, low heat emission, and light spectra optimized for efficient plant growth. However, the investment may prove to be wasteful if the crucial step of light planning is executed improperly.
Stop Measuring Light Quality in Watts
This old habit is dying hard.
For a long time, more watts meant higher light intensity. Cultivators who used HID bulbs developed lighting systems according to how many watts they needed to properly illuminate their grow facility.
But a watt is not a measurement of how many photons a lamp produces. It merely indicates how much power is needed to turn that lamp on. This may not have been an important distinction when there was a more direct correlation between watts and photons.
But times have changed. High quality LED grow lights produce the same light intensity as HPS and MH bulbs while consuming fewer watts.
So what number should growers look for? First, look for the PPFD metrics of a given unit. This number communicates the amount of PAR that will actually reach your plants.
Then, look for micromoles per joule. Micromoles tell you the amount of photons produced, while joules indicate the amount of energy consumed. High-pressure sodium lamps operate at 1.7 micromoles per joule. In contrast, quality LED lights run at an efficacy of up to 3.0 micromoles per joule.
In the modern market, the only reason to look at watts is to determine whether your current lighting system is using more energy than it needs to.
Monitor Light Levels for Energy Efficiency in Lighting
Most commercial growers have a system in place for measuring light quality across the canopy.
If you don’t already, consider acquiring a quantum sensor. This device measures PPFD. Of course, you should already have access to PPFD specs from your lighting manufacturer. But what we’re talking about here is monitoring light quality over time and within your unique grow space.
Many cultivators use sensor measurements for light mapping. The process of light mapping involves measuring light at specific areas of your grow room to monitor uniformity and light intensity. This allows you to catch inconsistencies and make adjustments. Those adjustments could help you better manage energy efficiency in lighting.
For example, an overlap in light footprints could create a hotspot. If you can eliminate that hotspot by spreading out the lights and even eliminating extraneous lamps, you save energy.
Hanging heights also play a major role in PPFD. Proper hanging heights for HID bulbs are less adjustable due to their high heat output (you don’t want to burn your plants).
But you have more wiggle room with LED lights. And if you find that your canopy isn’t getting the amount of PAR it needs, a lower hanging height does the trick.
Of course, this would only result in energy cost savings if you can lower the light and reduce intensity. But efficiency isn’t just about using less; it’s about eliminating waste. If your lights are too high, you might be wasting perfectly usable photons as light intensity depreciates when light escapes off the sides of the canopy.
Keep Grow Lights Cool
You may already know that LED grow lights emit almost no heat. This is another reason LEDs are the top choice for energy efficiency in lighting. Less heat radiation means less need for supplemental cooling—another major energy expense.
However, a lesser known detail is that high heat can limit efficiency and reduce the lifespan of a luminaire.
The best LED grow lights come with features to prevent overheating within the fixture. We designed our SolarSystem series with user replaceable fans and a housing that promotes heat dissipation. These features help us achieve the expected 100,000-hour lifespan for this unit.
Beyond light selection, you can help promote energy efficiency in lighting by maintaining a safe temperature for your lamps. Keep the thermal junction temperature of an LED light below 100 degrees, and you’ll get the biggest bang for your energy bucks.
Keep Up with Innovations to Improve Energy Efficiency in Lighting
Finally, stay informed.
The science of cultivation shifts constantly. We are always making new discoveries about what plants need. New findings allow manufacturers like us to engineer lights that don’t waste a watt on photons your crop doesn’t care about. This information also guides you through decisions about which type of grow light to purchase and how to program your light spectrum.
Technology is also advancing at a faster-than-ever rate. We’ve met a lot of growers who have taken years to get onboard the movement toward LED lighting. Why?
Because they were still working with old information. They didn’t realize how much full spectrum LED grow lights had advanced in efficiency, intensity, and overall function.
THINK THROUGH THE DETAILS FROM THE START
First-time growers should resist the urge to make rushed decisions.
“Look at your expenses, have the foresight and be careful with product selection early on,” said Coleman Retzlaff, who oversees U.S. Eastern Sales at Quest Dehumidifiers. “Don’t focus on the cost today. It’s worth paying for better build quality in order to get better energy efficiency.”
There’s an entrepreneurial mentality to hurry up and get growing, but if you pause and think critically now, you’ll save yourself time and money down the road. For example, decisions such as updating or adding insulation can seem pricey now, but will lower your future energy expenses and, ultimately, increase revenue. If you think through everything from facility to equipment, efficiency will be on your side.
PLAN YOUR SPACE
The first area where you can improve efficiency is your facility. Too often, growers overestimate the space needed to grow, and are left to foot the energy bill for controlling the climate of an unused space.
“The No. 1 thing is planning, planning, planning, in all facets – everything should be planned out at an annoying extent,” said Jared Dinsmore, a commercial grower. “It is imperative to get all the opinions out there and explore all the products available to you.”
Consider exactly how much space your plants need based on how much cannabis you plan to grow in your marijuana grow tent.
In addition to making the most of your plant space, remember to include room for you and your crew to walk, water, prune and fulfill general gardening needs. To make the most of your floor and work space, consider an overhead dehumidifier.
If you don’t have enough space, you will increase the time and energy needed to complete tasks, and there’s a lot to be said for maximizing labor efficiency.
WEIGH YOUR LIGHTING OPTIONS: LED VS. HPS
It’s difficult to determine which lighting technologies are worth pursuing. Though some growers are ready to jump to LEDs – or already have – many don’t believe LED lighting technology is on par with high-pressure sodium (HPS) lights.
During the vegetative state, plants don’t require intense light, so many growers save energy by using LEDs at this stage. For the flowering stage specifically, many growers believe LED lighting won’t give you the same yield you get with HPS lights. For this reason, many growers are willing to deal with the excess heat from HPS lights, which can mean more cost when it comes to cooling. By the way, quantum board led grow light also saves energy more.
Of course, the biggest holdup for LED adoption may simply be initial cost. LED lights can run $1,600 each, as opposed to $350 for traditional HPS lights. But, while LEDs may cost more upfront, the upside is they last up to 50,000 hours, require less energy and run cooler, which results in savings.
In addition to LEDs, there are other light options out there that could improve energy efficiency. Light emitting ceramic (LEC) halide lights, also called ceramic metal halide (CMH) lights, reduce electricity consumption but have a high heat output, so as with LEDs and HPS, you’ll have to weigh the pros and cons and figure out what works best for your setup.
THINK THROUGH WATER & HUMIDITY
In some states, water is inexpensive and drought may not be a concern, but for energy’s sake, it’s important to test and maintain a watering schedule. Overwatering is easy to do and a common way to waste water. Understand just how much water your plants need, and if possible, consider automating the watering schedule for your grow room.
“Pay attention to not only how much water you use, but where it goes after it leaves the plants,” Dinsmore said. “It’s important fertilizer run-off is disposed of properly.”
Similarly, leaving humidity up to chance is never a good idea. Out-of-control humidity creates ideal conditions for pests, odor, mold and mildew, which can devastate crops. Dehumidifiers counteract these problems but some – particularly those not designed for grow rooms – use a lot of energy. The best option is to consider energy-efficient units and properly size your dehumidifier for your grow room.
“Understanding temperature and humidity is pivotal to consistency in your grow and your energy expenses,” Retzlaff said. What's more, if you are a beginner, ECO Farm marijuana grow kit can help you more.
GROW YOUR OWN WAY
As technology continues to advance, competition and cost challenges among growers will increase the importance of energy efficiency.
Growers want energy-efficient products because they result in savings, so industry brands continuously innovate to benefit from releasing the “latest and greatest.”
From a business standpoint, embracing energy efficiency is a way to stay competitive because it not only helps with economic return, but also boosts brand perception.
According to a recent Cone Communications study, “nine-in-10 consumers expect companies to do more than make a profit, but also operate responsibly to address social and environmental issues.”
A great way to spend efficiently is to “build a good relationship with your hydro store because often they can get you better rates and deals,” Dinsmore said. “Know your local garden supply store and support them – they’re your lifeline – and even bring them a little something on Christmas.”
For now, the best strategy to developing energy-efficient grows differs across states, regions and climates. There are many approaches, and “gardeners are like microbreweries – nobody wants to follow a recipe … They’re all trying to hit their own sense of perfection with a blended mix of techniques,” said Retzlaff.
So, whether you care about energy efficiency because of cost, competition or personal beliefs, ultimately, find what works best for you and your grow room.
Choosing the right light spectrum strategy
Current offers a wide range of products for the specific lighting needs of growers.
“If growers want a specific light spectrum we can provide that for them,” Spalholz said. “We can also offer recommendations.
“There are two distinct scenarios: one is the greenhouse and the other is the indoor grow or vertical farm. For a greenhouse, we recommend a dichromatic or blue and red light recipe because the sun already provides natural green, orange and yellow wavelengths. In the photosynthetic active radiation (PAR) range, sunlight is composed of roughly 1/3 green light, 1/3 blue light and 1/3 red light under clear sky conditions. In indoor farms, we promote a more balanced or broad spectrum so growers can utilize the advantages of green and white wavelengths.”
Spalholz said the light recipes for some controlled-environment crops have been determined, but there can be differences between varieties.
“Especially with new varieties, there may be differences and it may take some trial and error to determine the best light recipes,” he said.
“Research has really opened up with the use of LEDs to test multiple factors, including the impact of light quality on transpiration, nutrient uptake and plant nutrient levels. From a practical aspect for optimizing production for some crops like lettuce, we’re very close. Other crops like strawberries with long life cycles where there are increased influences on the crop, the impact of light may not be readily seen until later into the crop life cycle. There is still a lot of research that has to be done on berry crops like strawberries. There can also be big differences in cultivar performance with cannabis and hemp relative to light quality.”