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Old 01-16-2013, 04:44 AM   #30 (permalink)
320touring
Master EcoModder
 
Join Date: Jun 2010
Location: scotland
Posts: 1,434

The Mistress - '88 Bmw 320i Touring SE
Team m8
Last 3: 27.17 mpg (US)

Germany Beadle - '91 Mercedes 300td (estate, N/A)
90 day: 24.63 mpg (US)

The Bloodylingo - '05 Citroen Berlingo Multispace Desire
90 day: 39.77 mpg (US)

Shanner Scaab - '03 Saab 9-5 estate Vector
90 day: 26.19 mpg (US)

Clio 182 - '05 Renault Clio RS 182 182
90 day: 31.73 mpg (US)
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Quote:
Originally Posted by christofoo View Post
So if you hypothesize that 'eco' halogens costs you $5 for one reason or another, the ROI is:
$5/(0.015gal/hr*$3.6/gal) = 90 hours of low-beam operation
Which is almost certainly within the lifetime of the bulb. (Or make it 200-300 hours if you throw away your old bulbs to put in new ones.)

So purely in economic terms, this type of bulb is probably worth using, even if you have no special purpose like an alt-delete or extensive after-dark engine-off time.

But clearly if there is no special purpose, this mod is about pinching pennies and splitting hairs. Although the electrical draw is easily measured, I'd expect the effect on fuel to be lost in the noise.

Top post! cant believe this has stimulated so much debat, but it is good to see

So you could expect to see an investmetn return within the lifetime of the bulb when using it as a dipped beam only?

Currently I'm running dipped beam to/from work 5 days a week on a 2hr return trip, making the payback period (in hrs operation) as 9 weeks (say 2 months)- so this could save me approx 1 impg Gallon over 9 weeks?


If so, I'm currently getting 25mpg on LPG, a 1 imp gallon reduction over 9 weeks would take me from 25 up to 25.21mpg..

worth it?
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US MPG for my Renault Clio 182


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