battery backup advice

[maflynn]

Any advice on battery backups would be great. Here's the situation.
I'm using a 15" unibody MBP and dsl modem. I lost power this morning and while the juice is back on the typical outage is several hours. We seem to lose power a few times a year. I tend to work from home a lot so its not a passing need.

Because I have DSL, if I power the modem, I'll have internet and I can work. I looked at an APC 1500va/865watt battery backup but that's > 200 bucks. I think they will give me the most uptime during those outage times. I'm looking to only plug the DSL modem and laptop and I'm thinking this will give me enough juice for few hours.

Thoughts, opinions, is my logic sound or am I off the wall with my thinking is the 1500va over kill for what I'm looking to do (run laptop + dsl modem for a few hours)

Edit:
The DSL modem is 13 watts and the power brick for the MBP is 85 watts giving me a total 98watts

 

[iBookG4user]

Battery backups are more for the purpose of running essential electronics for a short period of time to save your work during a power outage. They aren't typically made for what you're wanting it to do, instead I think you should consider a small generator. That would be built for the purpose that you want and doesn't cost that much.

 

[maflynn]

I understand the purpose but given the low wattage needs, and the ability of the APC XS series I think (or least hope) that it would fit the need. A generator is not a feasible solution in my situation.

 

[VeryOldTimer]

I think this is a great idea.

First of all you can't tell the runtime by the VA rating. You need to know how big the battery is. In APC's case they give you a runtime chart like this one.
http://www.apc.com/products/runtime_for_extendedruntime.cfm?upsfamily=23
You can look at the 100watt column to see how much runtime you will get.

I think you will find you will not need the 98watts. You can check your actual watts with a Kill-a-watt meter. Those are pretty cheap on newegg. Your MBP will use less than the brick's max rating. Also you can run on it's internal battery for a while buying you much more time for the DSL.

You will get hours of usage out of that UPS. I'd say it was overkill but if you regularly lose power for several hours then that is what you need. I recently lost power for a few hours myself and had a UPS running my cable modem and Vonage box. I thought I would be good however the cable itself must have lost power somewhere along the line and I still could not get on the internet. So even though you think this will cover you it may not.

 

[jdm111]

What i have is a USB powered modem connected to my PowerBook G4. It hasnt had to be used yet but it would probably stay up for 2:30.