Does anyone use a Halogen fixture for growing their plants? I have never seen one in use, but is there any specific reason as to why they are not used to grow plants? I ask because halogen seems A LOT cheaper than HPS or MH. It is possible to get a 500 watt halogen HQI fixture for $15, which is extremely inexpensive for the light output.

I believe they are made to use for commercial places like parking lots garages driveways they dont have the full spectrum light needed to grow plants.

I believe they are made to use for commercial places like parking lots garages driveways they dont have the full spectrum light needed to grow plants.

HPS is what is mainly used for parking lots and street lamps. It is not full spectrum either, but people use it to grow their plants under. It is always possible you could supplement something to make up for the lack of light in a certain spectral area.

Ok I asked the lighting guy who works at my local home depot and he said hps grow lights for plants have all the right spectrum and are more efficient. The same halogen lights used for parking lots are also hps but they lack the right spectrum and run very very hot which will fry the plants in no time.

Hi Nick,

There are a couple reasons why people use High Intensity Discharge (HPS and MH) lamps for horticultural applications instead of halogens.

The most important factor is PAR lumens per watt. Halogen lamps produce drastically less PAR Lumens (photosynthetically active radiation, a measure of photons, and what plants actually use) than their metal halide or high pressure sodium counterparts.

HPS and Metal Halide have the best spectrum for plant/flower growth, and are the most efficient providers of PAR lumens for the wattage used.

Here's a tip for you: I agree with Dean Hung when he says that marijuana forums are the the best resource orchid growers can find for information on growing indoors under lights. You would be amazed at the wealth of sound information you can find in the cannabis forums, and you definitely don't see any of the weed growers using halogen lamps. ;)

Just for comparison, a 175 watt metal halide produces the same lumens as a 500 watt halogen lamp. That is a serious difference in $$ for your monthly electric bill.

Lol Justin your right!I googled and found a ton of growing pot plant websites!!

Nick, save your money and don't bother getting a Halogen lamp for reasons already mentioned. Get a HPS growlight system instead for your greenhouse.

Nick, save your money and don't bother getting a Halogen lamp for reasons already mentioned. Get a HPS growlight system instead for your greenhouse.

I wasn't planning on getting a Halogen fixture. I was just wondering why it wasn't in use. I actually just upgraded my T12 fluorescents to VHO, so it is overdriving the 40 watt bulbs to 110 watts, so I am getting quite a high amount of light.

Hi Nick,

There are a couple reasons why people use High Intensity Discharge (HPS and MH) lamps for horticultural applications instead of halogens.

The most important factor is PAR lumens per watt. Halogen lamps produce drastically less PAR Lumens (photosynthetically active radiation, a measure of photons, and what plants actually use) than their metal halide or high pressure sodium counterparts.

HPS and Metal Halide have the best spectrum for plant/flower growth, and are the most efficient providers of PAR lumens for the wattage used.

Here's a tip for you: I agree with Dean Hung when he says that marijuana forums are the the best resource orchid growers can find for information on growing indoors under lights. You would be amazed at the wealth of sound information you can find in the cannabis forums, and you definitely don't see any of the weed growers using halogen lamps. ;)

I did a little research also. I read that the halogen has to heat up to 200C in order for the chemical reaction to occur within the lamp for it to function. The energy is wasted in this so that is why the lumen output is so low compared to other lights. It is more like a giant incandescent bulb.

Here was a very interesting site on grow lighting. Here is a section from it about Halogen.


INCANDESCENT LIGHTING

Cheap, low quality light

Incandescent lights are the ubiquitous screw-in bulbs you most likely have lighting your home. An incandescent bulb consists of a glass bulb with a tungsten filament in a near vacuum; just a small amount of argon or krypton is present. When current flows through the filament, it heats up and glows giving off both heat and light.
Halogen bulbs

A variation of the incandescent bulb is the halogen bulb. This is an improvement to incandescent bulbs invented by GE in 1958 for the wing tip navigation lights of the Boeing 707. In a regular incandescent bulb, the tungsten filament evaporates, and over time the inside of the bulb is coated with a fine coat of tungsten from condensed tungsten vapour. This coating will severely limit the light output of the bulb. In a halogen bulb, a small amount of one of the halogens (Iodine or Bromine are used) is present and combines with the evaporated tungsten. This Tungsten Iodide or Tungsten Bromide molecule has an affinity for the tungsten filament and returns there and splits. The tungsten from this molecule returns to the filament while the halogen returns to the atmosphere inside the bulb. This process does not work unless the bulb jacket is at least 200 degrees Celsius. This is why halogen lamps are so hot and must be taken into consideration. Halogen lamps are 25-30% brighter than regular incandescent bulbs. The halogen cycle, as it is called, takes place in a very small capsule, as it is easier to maintain the high temperature required for the halogen cycle to operate in a smaller space. This capsule is placed inside another glass capsule which serves as the bulb's outer casing and although it is still plenty hot, it is not as hot as 200 degrees Celsius.
Output spectrum is biased towards the red

The output spectrum of incandescent light, halogen or regular, is biased heavily toward the red. Non-halogen bulbs have a colour temperature of 2700K, while halogen bulbs have a colour temperature of 3000K - they are a slightly more whitish light. Both have a CRI of 100. A diagram of the spectrum looks rather like a triangle, starting with almost no output in the green and rising at an almost linear rate to the far red and infra-red. Although incandescent bulbs are very inefficient, they are a very good source of near and far red light which is certainly very important. They are sometimes used as supplements in systems which are deficient in the red end of the spectrum.
Efficiency

The great disadvantage to incandescent lights is their inefficiency - you don't get a lot of light compared with how much energy you put apply. One saving grace in this respect is that the efficiency increases proportionally to the wattage, for example a single 100 watt bulb is much brighter than two 50 watt bulbs. The energy that does not get converted to light is wasted by being given off as heat. All but the smallest wattage bulbs can generate an awful lot of heat, and this must be taken into consideration. Another point to consider is, because the heat is so great, a splash of water on a hot bulb can shatter it.
Halogen bulbs are more efficient than "regular" incandescent bulbs by virtue of remaining brighter longer; they still give off 95% of their initial light output at the end of their lives, which are about twice as long as regular incandescent bulbs. They are also more expensive.
The great advantage of non-halogen bulbs is of course their extreme low cost for initial purchase, and of course their great availability; you can buy them anywhere. Halogen bulbs are on the average 5 to 10 times as expensive as their non-halogen counterparts and can usually be found at larger hardware stores. Since their primary market is yuppie track lighting they are usually found as spot or flood lights. Of potential interest to grower is the low voltage bulbs used in some track lighting systems. Operating as 12V, these bulbs are quite small and would be good to use a supplemental light augmenting a fluorescent setup. They are also the cheapest of halogen bulbs. While I have seen them at $30 each in fancy designer light stores, I have also seen them in Price Club at 3 for $12. Sylvania makes a series of bulbs called Capsylite that come in "regular" bulb shapes plus the large parabolic reflectors sometimes used to illuminate the outside of houses. Osram makes a large array of different shapes and sizes, most of which look like the vacuum tubes. They are probably the most useful to growers because of their smaller size and wide range of wattages; from low power bulbs all the way up to 150 watts. They are however not cheap and can be quite a challenge to find somewhere that stocks them.


It has more on all the different types of lighting. A pretty good read!
http://retirees.uwaterloo.ca/~jerry/orchids/light.html

Ok I asked the lighting guy who works at my local home depot and he said hps grow lights for plants have all the right spectrum and are more efficient. The same halogen lights used for parking lots are also hps but they lack the right spectrum and run very very hot which will fry the plants in no time.

Maybe I could make a halogen greenhouse heater? LOL :lol:

Nick,

Please keep us posted on your results with the VHO fixture. I'm interested in HO/VHO fluoros.

Nick,

Please keep us posted on your results with the VHO fixture. I'm interested in HO/VHO fluoros.

I will do. I want to try and get a light meter in so I can test and see what kind of light intensity I am getting, but the nice ones are pretty expensive. The regular 40 watts get about 3000 lumens, so if I am overdriving them to 110 watts, then I should be getting approximately 8500 lumens per bulb, and I have a set of 4 over the plants.