Photo Update: Time-Lapse test shot (LED Lettuce)

Today the long-awaited red/blue LED experiment has gotten underway. That is, the plants have been moved into their new reservoir below the LED panels. I spent some time today setting up the time-lapse camera and getting the focus/etc corrected. Below is a test shot from that camera, indicating approximately how the time-lapse videos will look. It's a little strange that this setup is totally in the dark, but I want to exclude all secondary sources of light.

Some details you might find interesting:
-The camera is set up to take photos every fifteen minutes during the 'daylight' hours of the experiment.
-The lettuce is receiving 13 hours of light per day, so we'll get about 52 shots per day.
-The lettuce is being fed Maxi-Grow dry nutrient from General Hydroponics, at a concentration of 1 teaspoon per gallon.
-The reservoir holds 7 gallons of solution.
-The solution pH is being kept at 6.5
-Solution temperature is 68 degrees.

You'll notice the camera is set up a bit high, or that the plants appear very low in the frame. This is to make space in the frame for the (hopefully) explosive growth we're about to witness.

Photo Update: LED Lettuce Redux

Here are the test subjects for the LED Lettuce growdown. I have twelve pots of Bullet Romaine Lettuce, which have been germinated and sprouted under conventional fluorescent lighting. There will be six plants under each LED panel so that we have plenty of subjects to even out small discrepancies in the experiment.

As you can see, there has been prodigious germination here, pretty much every seed that I sowed has grown so I'll have to do a cull pretty soon to keep only the strongest-looking plants.

This weekend I will move these guys into their new home and set up the time-lapse camera. Every week I will post the time-lapse of the previous week's growth.

New Project: Red/Blue LED Grow-down

It's a week late but as promised, I have restarted the red/blue LED side-by-side comparison. In this new setup all plants will be grown in the same deep water culture unit, with one half of the plants receiving light from a blue LED panel and the other half receiving light from a panel with both red and blue LEDS:

Pictured here is a hasty shot of the system that I set up, shot from a mobile phone. There are a couple of small problems that need to be straightened out before the plants can go in- the floor isn't quite level under the system so the nutrient level would be slightly deeper at one side than the other. Also you can see that the red/blue panel is sagging just a bit and needs its outer edge lifted.

The crop will be Bullet Romaine lettuce (seeds from Territorial Seed Company). Having all plants grown in the same system will eliminate any errors due to discrepancies in nutrient mixing.

Where are the plants? They're all off together in a starter system until they germinate and develop roots, at which point they'll be moved into the deep water system.

One control that is missing from this experiment is a set of plants grown under conventional lighting. After the results of the LED experiment are in, I'll do another experiment using the winning LEDs side-by-side with a more conventional compact fluorescent grow light.

As a special treat, I'll be tracking this experiment via time-lapse camera, so there should an interesting video to watch at the end of things!

How To: Computing the cost of energy usage

Right now I don't have any material for a photo update, but I will later this week as I get the LED lettuce experiment re-started. For now I thought it would be interesting to share how I figure out the cost of energy used to run my bucket farm.

If you are involved in the hydroponics hobby or intend to get involved at some point, you'll need to manage energy usage to manage cost. Depending on your setup and your needs, you will be operating some combination of air pumps, water pumps, fans, lights and perhaps even heating and cooling appliances.

To get started, you need to know how much your energy company charges you for electricity. This is on your power bill and likely on your power company's website as well. This rate is usually expressed as the price per kilowatt hour of electricity used. In my case, this rate is nine cents (.09) per kilowatt hour.

You will also need to know the wattage of the device you are operating. This is easy with lamps, as they usually have the wattage printed on the bulb or base in almost all cases. With pumps, fans, etc, you may have to look at the box or see if the value is stamped on the appliance somewhere.

The formula to figure out how much it costs to operate a device for a certain number of hours is:

COST = ((DEVICE WATTAGE * HOURS USED) / 1000 ) * POWER RATE

Or, to use this formula in a practical experiment, lets say that I want to compute how much it costs me to run a 60 watt light bulb for 24 hours.

COST = ((60 * 24)/1000) * .09


Let's look at this step by step.

1. Multiply the wattage of the bulb by the number of hours it is used. 60 * 24 = 1440. This gives you the watt-hours of electricity used.

2. Divide the watt-hours by 1000 to convert them to kilowatt hours. 1440 / 1000 = 1.44 kWh

3. Multiply kilowatt hours by the price of electricity (9 cents in my case) 1.44 * .09 =0.1296

Thus, it costs me about thirteen cents (.13) to run a 60 watt bulb for 24 hours.

In addition, you can multiply this figure by 30 to figure out the monthly cost: .13 * 30 = $3.90 to operate a 60 watt bulb 24/7 for a month.

You try. Let's look at the cost of operating just my lamp. I use a 400 watt lamp and currently it runs for 13 hours a day because my peppers are now blooming and fruiting. How much does it cost me per day?

P.S. If you leave lights on around your house for other purposes, you should compute how much money you'd save by swapping your 60, 100 and 150 watt incandescent light bulbs out for 13, 26 and 42 watt compact fluorescent bulbs.

Happy New Year! (and a disappointment)

Best wishes for 2010 from the Bucket Farm! Now that I'm back from vacation I'm ready to settle in for more growing and more fun, I hope to see you all visiting often!

Now for the disappointment- due to an accident, my blue/red-blue LED lettuce experiment has been destroyed. Since the data from this experiment is so important, if only to myself, I intend to restart the experiment in a side-by-side comparison format (in a safer spot!) as soon as possible.