Battery Power useage

I have the 50D. Question: does the camera use more battery power to process the raw files when shooting raw compared to processing the jpeg? I am thankful I started shooting entirely raw but noticed that ever since I changed to shooting raw my battery dies in about 2 hours of shooting (bp-511a battery) and I have to change. My charger came with the camera which is about 2 years old and I never take the battery out of the charger until the charge light is fully lit and not flashing and the camera shows it fully charged.

Just trying to narrow down the problem of batteries going dead. When I first got the camera I shot raw sparingly and mostly shot jpeg. Could the raw processing and writing to the CF card (takes longer than jpeg) be the culprit?

Thanks for all responses.

With my old 50D I could take 600+ raw images per battery charge on a non IS lens. This would go down to 450 if I used an IS lens.

Hummmm...Ok, I had taken between 100 to 200 and using an IS lens. I guess I could turn off the IS and that would give me more shots? But does the camera writing the raw images to the card use more battery power as compared to writing jpegs to the card? I have always used the IS feature but only when I started shooting totally raw have they started dieing.

MGiddings Photography wrote in post #13360832
With my old 50D I could take 600+ raw images per battery charge on a non IS lens. This would go down to 450 if I used an IS lens.

At least for the Nikon D300, specifically the manual states (p. 415) that shooting in NEF (Nikon's RAW format) reduces battery life. The reason is simply not the production of a jpeg or a RAW file within the camera, but the writing of the much larger RAW file to the memory card.

In my Canon 60D manual, it kinds of hints at something similar, in that the "possible shots" for the best jpeg (filesize 6.4 MB) is about 490 whereas for the best RAW (24.5 MB)is 130. The chart does not go into what "possible shots" actually means.

Over time the batteries lose capacity so you will get fewer shots as time progresses.

Other things that affect battery life:
- pop-up flash
- IS usage
- Autofocus
- excessive metering
- review time after shot setting
- sleep time-out
- leaving the rear LCD on
- live view
- possibly having the orientation sensor turned on
- uploading images through USB from the camera
- ambient temperature
etc.

Because there are so many factors, it is hard to generalize about how many shots is normal.

Ok..thank you all for that info. Since I could do an 8 hour wedding when shooting jpeg on one battery, now that I'm shooting raw and it is down to about 2 hours per battery (shooting raw is the only thing that changed) then I'd say it is the raw being written to the card that is doing it.