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Old 09-28-2012, 09:29 AM   #35 (permalink)
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Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 52.48 mpg (US)
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Since we know taking the electrical/alternator load off the engine is absolutely going to save fuel, I would say those savings were off-set by increasing other loads:

1) the weight of the solar/battery system (probably a relatively small impact), plus,

2) the added aerodynamic load of the panel mounted on the roof which increased frontal area (A) and drag coefficient, (Cd).

Aero losses were probably a relatively larger impact compared to the weight gain.

It's discouraging to do all that work and not see the effect you were hoping for (been there, done that!).

Thanks for reporting unexpected results though. It'll help the next person considering this type of mod.
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown

has launched a forum for the efficient new Mitsubishi Mirage - fuel efficiency info for Geo Metro owners - electric car conversion on a beer budget
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