Here's a wild stat: If one year ago you had split $1,000 and bought equal amounts of stock in oil and gas midstream company MPLX (MPLX 1.17%) and Brazilian oil giant Petrobras (PBR 5.71%), you would have generated $360.38 in annual dividend income. These two companies combined for a dividend yield of 36% over the past year. 

The chances of generating that kind of dividend income if you buy shares right now are pretty low (see below), but that doesn't mean you can't generate some serious income from these two ultra-high-yield dividend stocks. Here's why they may still be worth a look.  

Aligned interests mean big payouts

Few things will reasonably ensure a favorable outcome for investors more than when their interests are aligned with a company's management team. Surprisingly, this isn't always the case, as the goals management needs to hit may not necessarily translate to growing shareholder value. With pipeline and processing company MPLX, it's very much in the company's interest to pay sizable dividends to its shareholders.

MPLX's largest shareholder is Marathon Petroleum (MPC 0.70%), and the vast majority of MPLX assets are designed to serve Marathon's refining operations. The two just signed a new transportation-services agreement that lasts through 2032.

Since MPLX represents both a key supplier of transportation and logistics and a cash-generating asset for Marathon, management has operated the business to ensure payouts can be sustained over the long haul. That means a payout that's well covered by cash generation -- it currently pays out about 60% of cash available for distribution -- and a manageable debt load -- the debt-to-EBITDA (earnings before interest, taxes, depreciation, and amortization) ratio stands at 3.5 times. Management has even declared special dividends when the business is doing exceptionally well, in addition to share repurchases.

What's also encouraging is that the company's capital-spending plans are much more modest than they were in the past. Annual capital spending in 2018 and 2019 was more than $2.5 billion, whereas today, management says it wants to keep annual capital expenditures (capex) around $900 million annually. That's slower growth, but the stock's considerable payout can make up for it. 

All in all, management's incentive to generate cash for Marathon means that investors in the stock can benefit, as well. As of this writing, the stock has a distribution yield of 9.3%. That's a lot of cash going into your portfolio. 

Higher risk, but the potential reward can be hard to ignore

Let's get the shocking news out of the way. If you look up Petrobras' dividend yield today, you'll see a forward yield of 49.7%. That's an eye-popping yield you should in no way count on going forward.

Petrobras' dividend is a variable-rate dividend that's set at 60% of quarterly cash from operations minus capital spending. Two quarters of extraordinarily high oil prices have led to a couple of bumper dividends in recent quarters. 

Even if we assume that Petrobras' dividend will go down from here, there are still some reasons to think that the company will be able to pay a decently high dividend for some time. The key to its success is the pre-salt offshore oil formations.

Oil production from these formations have absurdly low production costs -- lifting costs were $3.30 per barrel in the most recent quarter -- and it is becoming an increasingly larger share of total production for the company. Today, about 74% of its production comes from pre-salt fields, and it has another 15 offshore platforms slated to come online there between now and 2026. Even with high government royalty and tax rates, management estimates the total cost per barrel across the business is $42 a barrel.

Historically, Petrobras has been a highly indebted company with a poor operational record, but several metrics suggest that it's getting its act together. Since 2015, it has reduced total recordable injuries per million man hours by 76%. Its refinery utilization rate -- a general sign of operational efficiency -- reached a respectable 89% in the most recent quarter. And perhaps most importantly, it has reduced its overall debt load by $33 billion since 2019 to $53.6 billion and currently has $19 billion in cash on the books. From an operational and financial standpoint, this isn't the same company it was three to five years ago.

Petrobras still has plenty of warts. Its dividends are paid in Brazilian reais, and this currency has lost significant value to the dollar recently. Petrobras was also embroiled in Brazil's largest corruption scandals, which resulted in the company writing down over $19 billion in bribes, graft, and writedowns of overvalued assets. (Seriously, go look up Operation Car Wash).

That said, the company appears to be in a much better position to generate shareholder value with more efficient operations, an extremely low-cost production base, and a rather shareholder-friendly dividend policy. Investors shouldn't expect a near-50% yield, but even a fraction of that payment would be a nice dividend check.