What happens when you take (9) 35w Xenon HID lights and mix in (54) 3w Cree XR-E LEDs? This is a question I never imagined asking myself until speaking with fellow aquarist Luke, better known on the various forums as Liveforphysics or LFP.
Luke, an engineer by trade, has taken HID car lights combined with LEDs [...]
What happens when you take (9) 35w Xenon HID lights and mix in (54) 3w Cree XR-E LEDs? This is a question I never imagined asking myself until speaking with fellow aquarist Luke, better known on the various forums as Liveforphysics or LFP.
Luke, an engineer by trade, has taken HID car lights combined with LEDs to provide his aquarium with intense focused light with proper spectrum for his photosynthetic animals to thrive. These are truly spotlights and the end result is a Japanese look that adds life to his reef while being extremely efficient.
Here is Part 1 of my (GBD) discussion with Luke (LFP).
- (9) 35w HID Xenon bulbs in Projector Housings
- (54) 3w Blue Cree XR-E LEDs (~200 lumens each)
- 477w Total
click to enlarge
GBD: Before diving into this with readers, what is your background? How long have you been in the hobby?
LFP: I consider myself to be an amateur inventor and innovator. I love to design and build parts for engines. Improving racing engines and fuel efficiency oriented engines are a huge part of my life. I’ve been racing cars and motorcycles for 10years, and I currently sponsor two cars and serve as crewchief for one of them. I don’t have the time anymore to race a season myself, so I enjoy the sport through helping others. I’ve also enjoyed reefkeeping for 6 years along with diving on reefs around the world.
GBD: What do you do for a living?
LFP: My job is engineering critical systems for datacenters. This involves power generation and redundant system design, along with very elaborate multi-stage cooling systems capable of removing the 10’s of millions of watts of waste heat from the servers.
GBD: For starters, where did the inspiration come from to use HID Car Projectors?
LFP: I’ve been a laser building hobbyist for years and I’ve always enjoyed the physics of optics.
Ten years ago I had an Acura/Honda NSX. I remember it had the best headlights of any car I had ever seen. This was one of the first cars to ever use projection headlights, and it made an impression on me. I later wanted that fantastic lighting on my superbike, so I began shopping around. This was about 5 years ago, and I ended up paying many hundreds of dollars for the projection assembly from a wrecked M5 BMW. I took the headlight assembly apart on my GSXR1000 and mounted the projectors inside. I was immediately in love with the beams of projection optics. Razor sharp beams that penetrate and illuminate with incredible intensity and efficiency when compared with a reflector.
Recently, I once again wanted to retro-fit a vehicle with projection lighting, and I found that the prices on projection housings was about a tenth of what it used to cost. HID kits for vehicles had also fallen in price from many hundreds of dollars to below 100. These things helped me decide it would be reasonable and feasible to apply this technology towards reef lighting.
GBD: Optics can give some obvious focusing advantages, what did you hope to accomplish by using HID projectors? What were your goals for this project?
LFP: I set some big goals for the project. My biggest goal was to not light the glass. My previous lighting bathed the glass with lots of light. Much like watering a concrete driveway, lighting the glass doesn’t result in any helpful effects.
My second largest goal was to use less than half the power my previous T5HO+LED+MH hybrid lighting system used, yet reach higher lighting intensity over the places I want light.
My tank is rimless, and my previous lighting was setup to sit just a few inches off the water surface to minimize light loss. I never felt like I had that natural and free look that a rimless tank can have, and I wanted my new lighting system to help change that.
GBD: Let’s not keep the tech geeks out in the cold much longer, what components make up your lighting system?
LFP: I used 54 Cree XR-E series LEDs. I used only the highest output bins available to help me reach my very low power consumption goals. Each LED is creating around 200 lumens of blue light. This means just 4 of these LEDs produce more light than an entire 25 LED array of a first generation Solaris lighting unit, and only consume about 15w rather than 75w. Fortunately later models of the Solaris use improved types of LED.
The LED’s are on variable controlled current power supplies. They can be controlled with an electronic signal to vary between a gentle glow or high intensity blue spears of light.
The core of my lighting comes from Xenon gas discharge. I purchased 14 headlight projectors and 10 HID kits in various colors of bulb. I used a spectrum analyzer tool to look at which bulbs produced the wavelengths of light I wanted. I only ended up using 9 of the HID lights, as I felt I had reached my goal of lighting intensity without needing to add all of them.
GBD: Being for automotive purposes what are you using to power the ballasts? How about the rack?
LFP: The ballasts all use DC voltage between 9v to 32v. To supply this I choose to use a few server power supplies I had laying around. I modified the fan voltages to make the silent, and I improved the internal heat sinking of the parts that needed it.
For the structure of the light rack, I recycled a couple of old server racks that were in a pile of de-commissioned parts in a scrap pile at work. They provided me with the aluminum to use as a heat sink as well as the mounting surface and structure for the parts.
GBD: How does the new lighting system compare to the old?
LFP: My previous lighting system used 12×54w T5HO bulbs, along with 120w of LEDs, and 4×70w MH bulbs. It used about 1,000w total.
My new setup uses 9×35w Xenon arc bulbs, and 54×3w Cree LEDs. That gives me about 480w total power draw. That’s not a whole lot of power being used to light a 310gal SPS reef. My tank system as a whole uses less than 750w peak, and has an average power use of about 480w continuous. I’m a firm believer that through improved designs we can greatly lessen the power demands of reefkeeping.
GBD: Overall, how do you like the spotlight effect?
LFP: I was very pleased to achieve the razor sharp cut-off lines in my lighting that I desired. I adjusted the projectors to cut the beams off about 2″ from the glass on all sides of the tank. A tank looks very different when the glass isn’t being directly illuminated. It seems to appear less like a clearly defined glass wall holding water, and more like fish and coral floating in air. When I start using Ozone again, I’m looking forward to seeing this illusion further improve.
I will be making adjustments to spotlight positions and moving corals and swapping bulb colors around for a few weeks to see what I like best. I’m very happy with the freedom in lighting options this setup has provided me.
Part 2 & 3 of our discussion are up next with more photos & info.
Update: Part 2 can be found here.
