It’s been a tough time for renewable energy firms over the last few years.

The sector has faced an uphill climb as falling traditional energy prices, dwindling subsidies and tariffs as well as a glut of product has taken the wind out of turbines and placed shade over solar panels.

Stocks within the alternative energy sector have been a terrible place to put money and some — such as China’s Suntech Power Holdings (NYSE:STP) and Germany’s Q-Cells — have even filed for bankruptcy. All in all, renewable energy hasn’t lived up to its hype or promise.

But that could be changing with a new bill set to go before the Senate.

This isn’t a new package of feed-in tariffs or additional subsidies designed to keep failing firms on life support. Instead, this piece of legislation is taking a page right out of the oil and gas industries playbook: master limited partnerships (MLPs).

The MLP Parity Act could be a game changer for the industry as well as investors in the beleaguered firms.

A Big Funding Opportunity

One of the biggest issues for solar, wind and other renewable energy types is the cost vs. using traditional fossil fuels. As oil surged towards $150 a barrel and natural gas prices were in the $15 range, various alternative energy solutions made economic sense. However, with fracking unearthing countless amounts of energy across the globe, solar and wind have come to rely more heavily on subsidies.

Sponsored by Senator Chris Coons, the MLP Parity Act would allow U.S. wind farms, solar energy facilities and other renewable energy projects to form tax-advantageous publicly-traded business structures.

Using the structure would stop profits generated from being taxed at both the corporate and shareholder level since it would be treated as a partnership. The oil and gas industry’s been using the MLP tax structure since the 1980s. Congress allowed pipeline firms to structure as partnerships to stimulate construction of domestic energy infrastructure.

According to Coons and the other bipartisan creators of the bill, this treatment of taxes available to oil and gas projects gives them access to private capital at a much lower cost than investors in other energy projects. By allowing wind farms and solar fields to be structured as MLPs, they can attract more investors to the projects. After all, MLPs are designed as “pass-through entities” — similar to real estate investment trusts — and are required to pay their unit holders large distributions as they are not taxed at the corporate level.

Lowering the cost of capital is seen as a necessary step in order help make many of these projects a realty in the face of decade low natural gas and coal prices. Tapping the equities markets via MLPs can be a sure-fire way to reduce this capital cost.

Coons introduced a similar bill last year, but that measure languished. This year, analysts expect the bill to pass as it has much wider bipartisan and bicameral support. The MLP Parity Act even drew support from the lobbying group behind Exxon Mobile (NYSE:XOM), Chevron (NYSE:CVX) and other energy producer: The American Petroleum Institute.

Making a Play

For investors, having renewable energy projects structured as MLPs can certainly be seen as a huge win. So it’s easy to see why funds like the PowerShares WilderHill Clean Energy ETF (NYSE:PBW) spiked on the news.

However, not every Tom, Dick and Harry solar or wind supplier is going to win because of the bill. The biggest winners will be those that already own and operate renewable energy facilities that can be “dropped down” into the tax structure. Both First Solar (NASDAQ:FSLR) and SunPower (NASDAQ:SPWR) do own solar power facilities and could see benefits of the MLP structure. A better bet could be MEMC Electronic Materials (NYSE:WFR).

Just as unloved as the other two, investors in MEMC could see bigger results from the bill. Through its SunEdison subsidiary, WFR owns nearly 540 different solar farms that generate around 425 MW worth of power. It sells the power generated at these facilities to various utilities.

By “dropping down” these plants into an MLP, MEMC could finally realize some tax savings, GP distributions and perhaps profits for struggling shareholders. At its current share price, WFR is basically trading like a call option on the bill.

Another less risky option could be utility NextEra Energy (NYSE:NEE). The company is one of the largest residential and industrial power providers in the Southern states, but it is also one of the largest generators of wind and solar power in the world. Already very profitable and a dividend stalwart, NextEra could be a huge winner if the MLP Parity Act goes through since it will be able to benefit even more from its renewable energy facilities.

While the bill still has a chance to die in committee, its passing would surely light a fire under the renewables sector. And the bottom line is that, for investors, the biggest beneficiaries will be those firms that already own and operate such facilities.

As of this writing, Aaron Levitt did not own a position in any of the aforementioned securities.