"I am very pleased with the performance of our energy investments and I particularly like the refiners," says resource expert Curtis Hesler. The editor of The Professional Timing Service has also owned Valero Energy (NYSE: VLO) and Frontier Oil (NYSE: FTO) since 2005, and despite their strong performance, he says, "You should try and work these into your holdings during weakness."

Hesler explains, "Refiners have the ability to refine sour crude, which is becoming more prevalent on the market as the sweet crude fields peak out. In this process, sour high sulphur crude will make up more and more of available supply to the distinct advantage of those few refiners that can process it.

And yes, he adds, crude oil production is "already peaking out." He says, "I think you will find that once the numbers are gathered, 2006 will become the official year that global crude oil production peaked out."

He notes, "Another aspect of sour crude is that it sells for a significant discount to sweet crude, and the difference goes straight into the refiner's profit column. You will pay the same price for gasoline no matter what type of crude it is made from.

Frontier, he observes, has the advantage of being located outside the hurricane regions, and it's not susceptible to storm damage like Valero. However, he says, Valero has the ability to efficiently make 'boutique' gasoline blends. And he adds, "It is estimated that for every penny that gasoline prices move up, Valero makes an extra $1 million profit!"

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