The 33-year-old picked up a hamstring injury in pre-season and has not played a single minute for the high-flying Rams this campaign.
Much-travelled striker Bent will now attempt to keep bottom-placed Albion in the division after agreeing to swap a promotion battle for a relegation scrap.
Speaking to the Brewers' official website, the former Sunderland and Aston Villa man said: "One of the reasons I have come here is the challenge. It is different for me. The team is at the bottom of the table, but not far away, as it is really tight down there. One win puts you up four or five places.
"If I can help bring a bit of consistency to Burton I will be really happy. I have been renowned for a few years as a goalscorer and the objectives don't change wherever you are at, whether that's trying to help Derby into the Premier League or here at Burton trying to get goals to get them out of the relegation zone.
"I'm under no illusions about the challenge and it's one I'm really looking forward to."
Bent, who netted 13 goals in 42 appearances last season, is due to see his Pride Park contract run out in the summer.