Powering a laptop in a car?

[orion7144]

What is the best solution to use my laptop in my car? We will be taking a long trip soon and want the kids to be able to watch DVD's. I have seen all the little power inverters on Ebay but are they woth it? Like this one

Thanks

 

[gsaldivar]

Since you are thinking of running more than one device from the inverter, would suggest getting a full-size unit - they don't cost much more than the one you linked to:

See Coleman's 400- and 800-watt inverters at the bottom of this page (you can get them cheaper at Fry's etc.)

 

[gsaldivar]

Here are better prices:

Coleman 400 watt starts at about $24

Coleman 800 watt starts at about $65

Good luck!

 

[orion7144]

Thanks, they have a 5% coupon as well...

 

[mindless1]

The best solution is a genuine laptop power supply with a cigarette lighter plug. It takes ~ 11-14V in and steps that up to the voltage the laptop is spec'd to use... they are small and efficient, no point in converting back to Ac again for powering multiple devices, that just creates extra heat, wastes power.

To address the inverter you linked, don't get the crude tiny type, a regular full-sized invertor is better and provides cleaner output. It's also more versatile in that it will be more likley to power other devices than just the laptop.

 

[gsaldivar]

Originally posted by: mindless1
The best solution is a genuine laptop power supply with a cigarette lighter plug. It takes ~ 11-14V in and steps that up to the voltage the laptop is spec'd to use... they are small and efficient, no point in converting back to Ac again for powering multiple devices, that just creates extra heat, wastes power.

DC power supplies are pricey, laptop-specific, and won't provide an extra outlet for powering a non-laptop device. Other than those three drawbacks (deal-killers in my opinion), what you say is true: inverters are less efficient than specially built DC power supplies for laptops.

FYI As long as your car is running/idling, power efficiency isn't a that big of deal since your car's alternator will provide as much power as you need, as long as you have fuel in the gas tank. Efficiency will be a greater concern when your car isn't running, and you are draining the car's battery by using the inverter...