Carl Icahn's refinery investment has rebounded by $1.4 billion, boosted by Trump energy policy

Carl Icahn's refinery investment stumbled last year as the activist investor's push to overhaul U.S. energy policy stalled. However, that investment has now rebounded to the tune of more than $1 billion.

While Icahn's unsuccessful bid to change federal refinery rules indirectly dented the investment last year, the turnaround has been helped by the Trump administration's willingness to offer regulatory relief to the nation's oil refiners.

 In recent months, the U.S. Environmental Protection Agency has granted about two dozen hardship waivers that allow small refineries to avoid tens of millions of dollars in costs tied to a federal biofuels program.

The Oklahoma refinery linked to Icahn received one of the exemptions, according to Reuters, but the benefit of the exemptions goes far beyond a waiver for a single facility. The EPA's approach has slashed the price of complying with federal rules for all refiners, cutting expenses at a time when lower crude oil costs are boosting profit margins.

"A lot of these refiners have the best of both worlds," said Tom Kloza, global head of energy analysis at Oil Price Information Service. "They're seeing much wider refining margins than last year, and they're seeing much lower compliance costs."

Shares of CVR Energy, the refining and fertilizer business Icahn controls, have more than doubled since August, when the stock hit a 52-week low. Up to that point in the year, the stock price had slumped more than 30 percent as investors lost hope that President Donald Trump's EPA would overhaul federal policy to benefit refiners.