Trish Regan

Special for USA TODAY

Chances are you've been feeling a bit better about the economy in the last couple of months — and that optimism may have nothing to do with the stock market. Instead, you can thank lower prices at the gas pumps, a welcome boost to consumer spending power.

Despite increasing tensions in the Middle East, the nationwide average for a gallon of gas stands below $3 for the first time in four years — a roughly 20% drop from June levels. And OPEC, the oil-producing group that controls an estimated 40% of world supply and aims to keep oil prices as high as it can, seems to be just fine with that.

In fact, OPEC is apparently so comfortable with falling prices that investors expect its leaders to leave production unchanged, keeping plenty of supply in the markets, when it meets in Vienna later this month.

So, why would a cartel that aims to defend $100-a-barrel oil and depends on high prices for the success of its economies, allow oil to slip into the $80s — or even below $80, as it did Monday?

Simple. America's energy alternatives are becoming far too good.

In recent years, the energy renaissance in the U.S. has emerged as a growing threat to Middle East oil production. Shale oil, or "tight oil" as it's known, is oil secured from the ground by a process known as hydraulic fracking. U.S. drilling companies have become so adept at fracking that the U.S. is expected to become energy independent by 2020. Energy independence would diminish the importance of the Middle East. Understandably, OPEC isn't such a fan of tight oil.

For investors, the biggest problem with fracking is its high cost; oil prices need to stay above $85 a barrel in order for new fracking investment to be worthwhile. Harold Hamm, the CEO of Continental, a drilling company that controls most of the contracts in the oil rich Bakken region of the U.S., told me in an interview that at $75 per barrel, "people have to make some adjustments, and they have to do it quickly. You start drilling only what you need to drill."

OPEC knows that.

At a recent oil industry event in London, OPEC's Secretary-general Abdullah al-Badri told reporters, "If prices stay at $85, we will see a lot of investment going out of the market. About 65% of the producers, they have high costs. Not OPEC."

True. Oil is cheap to secure in the Middle East. And, therein may lie the primary reason OPEC won't budge on production.

In a pre-fracking world, lower oil (which is also being driven down by a stronger dollar and lack of global demand) would have been met by a restriction in supply by OPEC, in an effort to drive up prices.

This time around, should OPEC maintain current production levels, we should assume it is more interested in its long-term survival than in a current influx of cash.

So, as much as lower oil prices are good for consumers as we head into the winter months, it's critical we maintain investment in all forms of alternative energy, including renewables, here at home. If we hope to continue $3 a gallon at the gas pumps for years to come, allowing OPEC to regain control of the energy markets is not an option.

Regan is the anchor of Street Smart with Trish Regan daily at 3 p.m. ET on Bloomberg Television. Follow her on Twitter @Trish_Regan.