I bought a pair each of Sylvania EcoBright bulbs and Philips EcoVision, both 9003/HB2 size. Column1Column2BulbWatts (ea)OEM51 (spec 55W)Philips44Sylvania44 * *Sylvania's bulbs start out at 48W and slowly drop to 44 after about a minute. The Philips bulbs start and stay at 44. It's possible the Sylvania's would drop even lower with more time but I stopped to not drain my battery. Combined results (with LED tail & marker lights), car on but not running Column1Column2Column3Watts OEMWatts EcoNo lights3838Marker lights6641Headlights168129 That's a 23% improvement. I am currently running the Sylvania Ecobrights because of the dropping power consumption. They might (probably will?) settle at lower power than the Philips after a minute of warmup. Brightness and color are the same with all 3 (oem, philips, sylvania) under the scientific test of "stand 50 feet away and look at them".
In summary, the LED taillights and markers saved 25W and cost $110. These headlights saved 14W and cost only $13. Definitely better bang-for-buck. Overall I've gone from an estimated 12 minutes of headlights-on FAS ability to 16 minutes.
Not bad.. all that energy is coming out of your gasoline tank. The voltage was constant during this test?
Hi Andrew: How are you measuring the individual lights consumption as that sounds really interesting in itself! Wayne
Roughly constant mid 11 volts with the engine off. I retested with both OEM bulbs at the end and it came out the same. I'm not too concerned by the gas consumed to power the lights - the savings really are minimal. What I'm aiming for is better engine-off ability, which is a huge savings over running the engine just to power some light bulbs.
How did I measure? I disconnected the positive battery cable and inserted my ammeter in between the battery and cable. Turn on the lights, measure amps. Turn off. Swap bulbs, repeat. Then I converted to Watts with a simple Amps * 12V. The car draws 0.18A = 2.16W just sitting there. Security, remote door locks, clock and radio memory, etc. OEM headlights = 8.85A subtract .18A standby = 8.67 times 12V = 104W subtract 3W for taillights = 101W divide by 2 for each headlight = 50.5W
Good point! Brake lights are an interesting special case. When one is braking in gear, power to operate them effectively comes not from the fuel tank, but from a slight reduction in energy wasted by the brakes. That is, brake lights assist the brakes a bit. Of course it's a different story when the wheels aren't driving the engine.
