LED Grow Light Operating Costs
LED grow lights consume up to a third of the electricity required for conventional grow lights. However, they do draw quite a bit of power. This makes energy efficiency a priority when choosing between LED grow lights. It also means you need to take the LED grow light operating cost into account when budgeting for your indoor garden or hydroponics operation.
How to Calculate LED Grow Light Operating Costs
A good estimate for the power usage of a 600 watt LED grow light is 100 watts. Grow lights like this are going to have a 1.5 by 1.5 grow area. You can use the estimated cost of 15 cents per kilowatt hour. A 100 watt bulb uses 0.10 kilowatts. Multiply kilowatts by cost per hour by the number of hours the bulb is used per day.
In this scenario, a 100 watt bulb used 12 hours a day with 0.15 dollars/kwh costs 0.10x12x0.15 or 0.18 dollars to run per day. That light costs that amount per day, so multiply the value by 30 to estimate costs per month. Eighteen cents per month multiplied by 30 days equals $5.40 dollars a month to run. It will cost about $65 dollars a year to run.
Compare this to a high intensity discharge light or 600 watt bulb. It uses six times as much power. Thus with the same power usage, it would cost $389 to operate for a full year.
Common Mistakes People Make When Estimating LED Grow Light Operating Costs
One mistake people make when estimating LED grow light operating costs is that they use the wattage that the LED grow light is equal to instead of its actual usage. For example, they read that they grow light is equivalent to a 1000 watt HPS grow light and assume it uses 1000 watts. In reality, the LED grow light will use a third to half as much power. Fortunately, this will result in someone estimating their power bill to be two to three times greater than it actually is.
Another variation of this mistake is overestimating power requirements of the LED grow light. When you have a full spectrum light only displaying red or blue light, it isn’t using all of the grow lights. This means it uses a fraction of the power it normally does.
Tips For Lowering LED Grow Light Operating Costs
The grow light may use additional power if it is overheating, whether the shorts are consuming extra power or the excess heat pushes the cooling fans into overdrive. Excessive heat generation is a warning sign, too, since this may mean it is about to burn out and could cause it to catch fire. Give the grow lights adequate space and air flow to stay cool, and fix whatever is causing them to overheat. This also means that having a lot of grow lights crowded into a small space will force you to run extra fans or an air conditioner, driving up your electric bill.
You can lose energy when your grow light electrical system is inefficient. For example, you’ll have loss when the lights are connected to the power plug by a series of extension cords. This means daisy chains are more convenient but add a few percent to your electric bill. The opposite of this are LED chips on a board.
The single power system for half or all of the board reduces energy loss in the circuit. That means the more expensive LED COB systems have a lower energy demand than comparable LED grow lights. Unfortunately, it means that if the LED circuits burn out, you lose a large section of the grow light’s capacity in one go.
On the flipside, you will not lose a lot of power when you have a dozen individual boards in an LED grow light array, though shorted out bulbs will cost you a fraction of the energy. Take care of burned out bulbs as soon as you see them. At a minimum, this will prevent excessive load on the remaining bulbs and lower the risk of catastrophic burnouts.
Don’t try to minimize energy costs by using light concentrators. This will result in sunburning in the area that gets the most light and prevent the rest of the plant from getting enough light. Install red-blue grow lights that give the entire grow area sufficient light.