There are a few options with this as regards bulbs.
The actual Insight headlight/shape is fairly unique and you can't put an alternative unit in as far as I know.
The Oem bulb is a standard H4 Halogen 60/55/watt double filament type.
You can get higher rated Halogen bulbs in terms of power (watts) and light output (lumens), however replacing the normal bulb with a 100/80watt bulb means increased heat (possible damage to headlight unit and or wiring/switches) and more drain on the vehicle 12v power. Not recommended.
You can use a higher light output Halogen (Xenon) bulb with the same power consumption. I personally use Osram Silver Star +50% bulbs which use the same amount of power, but give a claimed 50% higher output as they burn brighter (probably shorter lived as well). These do work well and both my cars have these fitted, the uprated lights provide noticeably better illumination. probably about $10.00-$15:00 a pair.
You can fit aftermarket 35w H4 HID (high intensity discharge) bulbs if you really want to be daring. these give a massive increase in light output (claimed 200-300%) with the added benefit of approx 40% less power consumption. They do have some issues, they are very expensive $200-$300 and may not suit the Insight reflector pattern, possibly dazzling
other road users and causing the vehicle to fail inspections. They may be unlawful as an aftermarket conversion in your area. They run at a high voltage
and use a special ballast unit which should plug and play with the existing Insight wiring.
Take your pick.
Driving at night generally means air intake temp is cooler, this means slightly less effcient combustion and lower mpg. The total extra nightime electrical load is probably about 200W more than the daytime base vehicle load. This isn't much but may make a very small impact on mpg. Aircon is probably off or less active so that should improve mpg quite a bit. Pump those Oem tyres up hard and drive at <55mph for max mpg.
Peter
Lights
