The Oils-Energy group has plenty of great stocks, but investors should always be looking for companies that are outperforming their peers. SunPower (SPWR) is a stock that can certainly grab the attention of many investors, but do its recent returns compare favorably to the sector as a whole? One simple way to answer this question is to take a look at the year-to-date performance of SPWR and the rest of the Oils-Energy group's stocks.SunPower is a member of our Oils-Energy group, which includes 256 different companies and currently sits at #15 in the Zacks Sector Rank. The Zacks Sector Rank considers 16 different sector groups. The average Zacks Rank of the individual stocks within the groups is measured, and the sectors are listed from best to worst.The Zacks Rank emphasizes earnings estimates and estimate revisions to find stocks with improving earnings outlooks. This system has a long record of success, and these stocks tend to be on track to beat the market over the next one to three months. SPWR is currently sporting a Zacks Rank of #2 (Buy).The Zacks Consensus Estimate for SPWR's full-year earnings has moved 44.54% higher within the past quarter. This shows that analyst sentiment has improved and the company's earnings outlook is stronger.Based on the most recent data, SPWR has returned 181.92% so far this year. Meanwhile, the Oils-Energy sector has returned an average of -26.21% on a year-to-date basis. This means that SunPower is outperforming the sector as a whole this year.Breaking things down more, SPWR is a member of the Solar industry, which includes 12 individual companies and currently sits at #190 in the Zacks Industry Rank. On average, this group has gained an average of 174.11% so far this year, meaning that SPWR is performing better in terms of year-to-date returns.Investors in the Oils-Energy sector will want to keep a close eye on SPWR as it attempts to continue its solid performance.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report SunPower Corporation (SPWR): Free Stock Analysis Report To read this article on Zacks.com click here.