Recently, the price of oil has risen back to the $100 a barrel level and is far above its September lows. Since the world isn’t likely to kick its dependence from the bubbling crude any time soon, an investment in big oil is the way to go.

I watch more than 5,000 publicly traded companies with my Portfolio Grader tool, ranking companies by a number of fundamental and quantitative measures. And this week, I’ve got five big oil stocks to buy.

Here they are, in alphabetical order. Each one of these stocks gets an “A” or “B” according to my research, meaning it is a “strong buy” or “buy.”

Exxon Mobil (NYSE:XOM) is one of the largest and most well known oil companies in the world, and it boasts a market cap of nearly $390 billion. XOM stock is up 10%, year-to-date.

Royal Dutch Shell (NYSE:RDS.A) is an independent oil and gas company that owns Shell. In the last year, RDS.A stock has climbed 6%.

Chevron (NYSE:CVX) owns subsidiaries that are involved with petroleum operations, chemicals operations, mining operations, power generation and energy services. CVX stock has gained 14%, year-to-date, compared to a gain of just 4% for the Dow Jones in the same time.

ConocoPhillips (NYSE:COP) is a global, integrated energy company. In the last year, COP stock has climbed 5%, much like other big oil companies.

Statoil ASA (NYSE:STO) is an international, integrated oil company based in Norway. Despite losing some ground in September, STO stock is still up nearly 9% in 2011.

Get more analysis of these picks and other publicly traded stocks with Louis Navellier’s Portfolio Grader tool, a 100% free stock-rating tool that measures both quantitative buying pressure and eight fundamental factors.