daylight harvesting system cost estimate
daylight harvesting system cost estimate
(OP)
I am looking for a ballpark estimate to install a daylight harvesting system in an elementary school. The light fixtures are newer model t-8's. would $3,500 per classroom cover the new ballasts, photosensor, controls, etc?






RE: daylight harvesting system cost estimate
RE: daylight harvesting system cost estimate
What is that???
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: daylight harvesting system cost estimate
Because the building was designed in 1917 the classrooms were designed with high ceilings and tall windows to allow good penetration of insolation to the back wall of the classroom.
Actually the lighting controls cost will be a small fraction of the window cost. Around 10%.
Does anyone have experience with electrochromic window surfaces? ie reliability, & documented variation of shading coefficient?
RE: daylight harvesting system cost estimate
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: daylight harvesting system cost estimate
RE: daylight harvesting system cost estimate
I would investigate the proven life expectancy of "electrochromic" window surfaces prior to committing.
This kind of reminds me of when a undesirable open ditches became green project biofiltration swails.
RE: daylight harvesting system cost estimate
" "Day light harvesting" seems like a lot of technology and new jargon to accomplish what the original windows did back in 1917."
Thats kind of what it is. If your next to the window you don't need the light on. The guy on the opposite side of the room may need the fixures over his desk on however. The energy codes in a number of states require that fixtures in a room next to the windows be switched and controlled seperately. If a room has on wall that is esentially glass the fixtures next to the windows would be controlled by an ambient light sensor. On a bright day the area next to the window will have enough light weather or not the fixture in that part of the room are on or off.
If it's a bright hot day and the blinds are drawn the control system would sense the blind position and turn the fixtures on at a lower lever. It usually takes more energy to run the AC system than to operate the fixtures next to windows.
Here's Californias energy code, only 108 pages for lighting. Reading it for a few weeks will make it very clear.
ht
RE: daylight harvesting system cost estimate
I was just trying to get a grip on the term.. I did solar home judging for the state of California analysing 160 designs and we never came across that term...
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: daylight harvesting system cost estimate
I could have bbe using the term incorrectly. If so I wasn't the only one. The installations I worked on were commercial. If I google "daylight harvesting" now it seems a lot of manufacturers have ursurped the term and applied it to their control system.
to me and the ones I worked with it ment you should be able to turn off the lights by the window.
I am not doing any more lighting systems until they start making DALI ballest with unique identification switches. That way you can control ( a single twisted pair) and power to all the fixtures and control them anyway you can think of.
It seems to me the manufactures of existing lighting control systems are dragging their feet because a true DALI system would make a lot of control systems obselete PDQ.
RE: daylight harvesting system cost estimate
The costs really depend upon what system is selected. The aforementioned system for example, carries about a $125/ballast cost, plus some additional wiring and control devices. So in a typical 30 x 40 kindergarten class with 16-2' x 4' fluorescents, you can see that you are looking at 32 ballasts, (unless you tandem wire the fixtures). 32 x $125 = $4000.00+. That would be a tough payback period to sell. Unless you are going for some kind of LEEDS certification, the District would really need to be "Green-minded".
RE: daylight harvesting system cost estimate
I used to do work in California back in the early 90's. At that time Title 24 did not really affect our design too much, mainly just a lot of paperwork.
RE: daylight harvesting system cost estimate
RE: daylight harvesting system cost estimate
I have only seen a cople of commercial LED downlights.
RE: daylight harvesting system cost estimate
RE: daylight harvesting system cost estimate
Good luck I found this to be a inexpensive alternative to other systems that had a lot of control wires etc.
RE: daylight harvesting system cost estimate
http://www.greentube.co.uk/page5.html