Comment

Comment by Rob Torcellini on January 5, 2012 at 6:51pm

they flowered for most of the summer so I *thought* the bees were pollinating them.  I had no problem with the cukes, tomatoes, etc.  Water chemistry was all normal.  Most of the flowers would fall off.  I wasn't overly upset since I don't really like eggplant.  

I'm currently logging in the greenhouse:  outside temp, inside ceiling temp, inside temp near the floor, water temp, light level, times when each growbed is filling.  Based on the water temperature, the fish automatically get fed the appropriate amount of food.  Ceiling temps are tied to the vents which auto open and close along with comparing the tank water temp to the ceiling temp and turn on a circulation pump to try and extract waste heat from the ceiling and put it back into the water.  And, just for kicks, I record the rainfall and wind speed and direction.  greenhouse tour

Comment by Jesse Hull on January 5, 2012 at 6:30pm

Rob, did they flower and not fruit, or did you just get nothing at all?  

I have to shake my plants regularly or hit them aggressively with a fan for several minutes once flowers form to get them pollinated.

RE: "logging stats..."  Does your control equipment allow for computer interfacing or continuous data logging of another sort?

Comment by Rob Torcellini on January 4, 2012 at 4:44pm

I'm just impress you have eggplant.  I think I got 2 fruits from my 6 plants this year....that's 2 more than last year. 

Crunching the numbers is always a challenge....I've been logging stats from my greenhouse for the last 3 years...still not sure what to do with it all! 

Comment by Jesse Hull on January 4, 2012 at 2:45pm

That's a vast question that I've spent many years trying to log and quantify.  One problem is that lamps of all sorts keep getting marginally better every year... or they're just hyped to be better, in which case I still have  to do a 30-60 day trial to be sure (and of course one test doesn't really make me sure).  

LED's are touted as being the most rapidly advancing light source.  All I can say is that I'll be the first customer if a company can send me one that grows a crop producing the same harvest qualities I'm used to getting with "comparable" light sources.  Won't it be great to get an efficient, long life, low heat artificial light that can REALLY compete with a 400-600watt HID?  

In all honesty my favorite lights to grow with are still point source lights like HIDs (yeah, I'm a dinosaur in disguise), but they don't work well in many hydroponic/aquaponic systems such as tightly stacked beds, etc, and the bulb life (taking into account lumen depreciation) pretty much sucks.

On that note, the life of the lamp is, as you stated, an important consideration.  This is what attracted me to induction lighting.  The prototype fixtures I'm testing now will boast a 5 year warranty on the entire fixture when they hit the market, including the ballast and bulb, while the bulb is actually rated for ~100,000 hours (90% of the initial lumen output at ~70,000hours).  Not bad...

RE: "my overall goal is to see how to minimize the cost of growing by AP systems while maximizing the growth in a given size/space when faced with such environmental challenges around both USA and the world". 

... you and me both brother!    I've turned down good paying jobs to continue pushing commercial aquaponics.  

I think we all go through times of wondering if this can work on a large scale, especially after looking at schematics and financial spreadsheets for days on end.  

Log the data and keep the faith.

Comment by Sahib Punjabi on January 2, 2012 at 7:14pm

Thank you Jesse :-)

I know that you would have calculated both. What I am actually seeking is "extra cost" of this one element in a controlled environment. I know that our power costs are fairly similar across USA so your data as to the amount of bulbs used / hours on etc. and plants grown in the time period will provide an insight in the overall "cost" of the final product.

My next question was going to be as to whether you have had a chance to evaluate the differing lighting systems and what difference you have noticed re cost in achieving the same intense light environment. I am looking at the difference in the ballast supported lights, the sodium bulbs and LED lights. Initial hard are costs differ, but if one considers the overall life span of each, I am really interested in the overall costs associated with each of these  types. 

Jesse, my overall goal is to see how to minimize the cost of growing by AP systems while maximizing the growth in a given size/space when faced with such environmental challenges around both USA and the world.

God bless

Comment by Jesse Hull on January 2, 2012 at 5:50pm

Hi Brian,

T5HO bulbs already put out less light (and definitely less canopy penetration) than I'd prefer for adaptive garden production, and putting a less efficient and less intense light source such as T8's and T12's closer to a plant only works up to a point and only under certain situations.  

T5's also contain less mercury (important when disposing of the bulbs) and because of the smaller diameter can be placed closer together resulting in more light from the same sized fixture (but only up to a point).

Sahib,

Did you mean to ask if I've calculated the cost of running the bulb in relation to yield/production, or simply the cost of running, e.g., a 432watt (54w/ 4ft bulb), 115volt T5HO lamp?  

Considering the math is fairly easy, I'm assuming you meant the former; however, in either case the answer is yes.  Molly will confirm that I am a data logging junkie, and I've been late for dinner, etc enough times for that reason alone.  

It's site specific though.  I've never consistently achieved the same yield from one environment to another just by using the same light source and plant genetics.  All of Imagine AP's commercial scale designs for instance, are based on particular well-tested modules that are repeated to fill the given space.

The small lab we're using now is designed to produce the greatest output using the smallest input.  I then change one variable at a time.  In the case of the last few trials, that variable has been the light source.  

 

Comment by Brian on January 2, 2012 at 4:11pm

Sahib,

T8 lights are also effective and much, much less expensive. However, with only 35 watts you need to lower the lights to within an inch of the plants to achieve good results. If you want to grow in a cold weather climate like Michigan, T8's are an effective alternative.

Comment by Sahib Punjabi on January 2, 2012 at 4:01pm

Love it :-)

Expensive lights...Jesse have you ever calculated cost of running such lights?

God bless