What forms of lighting give you the best bang for your buck?

[Dustin Bajer]

In the experience of the forum, what is the best (most effective and most efficient) way to light a system?

I'm a teacher and permaculture designer working at a high school in Edmonton, Alberta, Canada (JP Permaculture).

Roughly a year ago, we built a 1300L flood and drain system in the school's culinary arts room and are using a large 1500W cfl to light it (with mixed results). We are, however, planning an expansion (adding 70 square feet of grow bed) and are going to need some better lighting options. I have been considering LED's but they are expensive, I have access to virtually free sodium lights but they are energy hogs. 

In the experience of the forum, what is the best (most effective and most efficient) way to light a system?

[Vlad Jovanovic]

The most effective and the most efficient way to light a system IMO, is the Sun . In second place are HID's. (MH, HPS, CMH...with CMH (ceramic metal halide) in all likelihood the best of the bunch. Watt per Watt, dollar for dollar HID's are the cheapest, most effective, easiest to maintain etc...

When you say "sodium lights" can you be more specific, since there are different types...HPS (high pressure sodium) are great, while say LPS (low pressure sodium) really suck as they are virtually monochromatic...CFL's are about the worst, for a number of reasons) IMO...(unless we count PL-lighting as a CFL...which technically it is...http://community.theaquaponicsource.com/group/artificiallighting/fo...)

There is a whole group here for all things artificial lighting http://community.theaquaponicsource.com/group/artificiallighting?

That you can check out/join...

And you can use the "search" field as well, since there have been many, many discussions on the topic (T-5 vs. HID cost to own blablabla...ones like this thread http://community.theaquaponicsource.com/forum/topics/nutrition-in-p...

Hope some of this helps...

[Jesse Hull]

Hi Dustin, the answer depends on what your goals are...

I spent the last several months growing with induction fluorescent lamps (link 1: lettuce, link 2: tomatoes), which can last 10+ years and keep the majority of the initial lumen output for most of it's lifespan.  They definitely have their pros and cons depending on the design.  They are also pricey, so the ROI will take awhile, and in 10 years who knows what advancements will be made that will make these and other lights obsolete.  

HIDs have had my vote through many years of horticultural light trials.  If you're referring to photons/lumens per watt, re: "bang for the buck", and stay in the 400w and above range this is your best option.  With air, or better still, water  cooled lighting you can make HIDs work in just about any space large or small in my experience.  Ceramic Metal Halide HIDs are very attractive, and I hope to start playing with at least one CMH lamp soon.

T5 fluorescent does well, although it will produce less photons per watt than HIDs.  Don't buy into the 'T5's are cooler' schpeel ... the laws of physics haven't been broken here 

Reflector choice is critical when using Induction, HID, or T5.

All of the LEDs I've tested either weren't worth the time it took to hang them, or performed well enough so long as they were used to grow vegetative plants no taller than 4-6 inches.

Oh, and last thing, Vlad's correct-  the sun is your best source as long as it's there and not blocked by intense cloud cover, which many places are during late fall, winter. and early spring.  Shorter days are also a big factor.  I've grown in greenhouses and indoor systems alike for many years, and until I have the time and money to build an adequately insulated greenhouse with an efficient heating/cooling system, I prefer the indoor approach.

[Jon Paul]

High pressure sodium and metal halide lights are possible your best option. High Pressure Sodiums give almost the same lumens per watt as LEDs. LEDs have unlimited coller options, are quiet, start up instantly, and operate very well in cold weather. If you had unlimited money LEDs would work well. I would go with high pressure sodium or metal halide. Or you could go with t5 lights. T5 lights started coming out about 5 years ago. 5 years ago I installed them in a factory to replace the high pressure sodium lights. Because the t5 were relivivly new at that point in time, I had problems with many of the lights. 3 months ago I removed 60 matal halide fictures at a YMCA in town and replaced them with T5 light fictures. The fictures were more expensive than the metal halide, but worth the money. There were also LED lights installed on that job. I and the customer were very happy with the t5 lights and not happy with The LEDs as they cost a lot, were not bright enuff, and had almost the same lumens per watt at the T5's

T5 lights cost a little more than High pressure Sodium and Metal hilide but have very high performance and are possible the best bang for your buck! T5 matnence is very easy. Every 3 years you clean the fixture and replace all of the bulbs. Replacing balists is done if light bulb replacement does not work and usually takes me 30 min per fixture. this has to be done every 8-20 years.
an investigation of t5 bulbs would need to be done. I'm not sure how well the stock bulbs work for growing.

Don't forget about plasma induction lighting. It is the most effecint lighting available. I have only installed 2 of these lights. They were about the same price as led but had longer life and were more effeciant. The fictures I installed had the best worenty on any light I have seen. I saw one person using them as grow lights before and they clammed that it was the best type of lighting.

I have a greenhouse in my back yard. I'm thinking about putting lights in it to control hours of light so I can effectively grow year round. Because of dark sky laws in my city I do not want to use High pressure sudium, metal hilide, T5, or plasma as they all would light up my greenhouse like a baseball field and make my nabors mad. So I'm thinking about using LED I like there cold weather preformence and how they can be bought any any color. I will choose a dark blue purple color that is not bright to the eye but gives the plants the reds and blues that they need. If this color makes less of a disturbance to the nabors, it will be worth the extra cost.