Investors looking for reliable income stocks will likely find attractive high-yield candidates in the energy sector. Don't pass these ideas by, thinking carbon fuels are a dead end. The world will need oil and natural gas for decades to come. The question to ask of the energy stocks you look at is: What will they do between today and the cleaner tomorrow?

Here's why ExxonMobil (XOM 1.84%), TotalEnergies (TTE 1.06%), and Enbridge (ENB 0.81%) are three stocks that can all provide you with decades of passive income despite their oil exposure.

1. ExxonMobil is big enough to change

Global integrated energy giant ExxonMobil is huge by industry standards, but also on an absolute basis. To put a number on that, the company's market cap is $450 billion. And it has an investment-grade-rated balance sheet. These two facts give the company, which generates the bulk of its revenue and earnings from oil and natural gas-related operations today, the wherewithal to buy its way into new business lines.

An oil well with clean energy wind turbines in the background.

Image source: Getty Images.

That was on display recently when it agreed to acquire Denbury Resources (DEN) for $4.9 billion. The news release made sure to note that Denbury is an "experienced developer of carbon capture, utilization, and storage (CCS) solutions." The investment is tiny relative to ExxonMobil's market cap, so this isn't a major overhaul of the business. But it shows that ExxonMobil can and will invest in clean energy when it thinks it makes sense. The funding for such actions, of course, comes from the company's carbon fuel profits.

Those oil and gas profits also fund the stock's 3.3% dividend yield. That dividend has been increased annually for four decades and counting. Given the ongoing material needs for carbon fuels, and ExxonMobil's size and financial strength, long-term dividend investors can own this reliable dividend stock and rest comfortably, knowing that it will use its oil profits to change with the world around it. ExxonMobil's just going to change in its own time.

2. TotalEnergies is getting ahead of the curve

All oil companies aren't biding their time, like ExxonMobil. For example, TotalEnergies, which has a 4.7% dividend yield, has been investing in clean energy for years. In fact, the French company now breaks out what amounts to a clean energy division when it reports earnings each quarter. While it is just 6.5% or so of adjusted net operating income, it is still a huge business. 

What's notable about TotalEnergies' investment here is that it has undertaken the expansion of its clean energy footprint without resorting to a dividend cut. European integrated energy peers BP and Shell made similar clean energy commitments but paired them with dividend cuts. 

TotalEnergies isn't as big as ExxonMobil, weighing in at "just" a $150 billion market cap. But the early move into clean energy shows that it can keep rewarding investors with reliable dividends even as it adjusts to the world's move away from carbon fuels. And like ExxonMobil, it is using oil profits to fund its efforts. 

3. Enbridge keeps commodity risk low

ExxonMobil and TotalEnergies have both made clear commitments to their dividends. That's great, but conservative investors might not like the fact that the revenue and earnings of both are highly dependent on volatile commodities. Canada's Enbridge, and its hefty 7.3% dividend yield, avoids that complexity. It is one of the largest midstream companies in North America, with a portfolio of energy pipelines, storage, and transportation assets that would be difficult, if not impossible, to replace.

What's important about the business is that Enbridge is a toll taker, charging fees for the use of its assets. The impact of fluctuating commodity prices is minimal. In fact, the business is a very reliable cash generator, which has helped the midstream giant build a nearly three-decade-long streak of annual dividend increases. As long as the world needs energy, Enbridge should continue to pump out cash.

Like the above companies, Enbridge has also been shifting its business model toward cleaner options. For example, its capital investment plans include relatively little investment in its oil pipelines, with far more going to natural gas pipelines, its natural gas utility operations, and a growing renewable power division. Sure, oil is the biggest business today, but the future looks increasingly less dirty. And you can collect reliable dividends while it builds for the future (using its profits from the oil sector).

Big today and big tomorrow

If you hate energy stocks because of the carbon connection, you shouldn't buy any of these reliable dividend stocks. But if you are worried that they are going to become obsolete as the world transitions to new energy sources, don't be. ExxonMobil, TotalEnergies, and Enbridge are all capable of rewarding investors well today and tomorrow, even while they take the steps needed to adjust to the increasingly clean energy times.