We aren't even through the first quarter of 2023, and it's already been chock-full of winners, losers, and massive moves (as recently seen in the financial sector). And while it's easy to hop onto whatever bandwagon is working at the time, long-term investors know that the most significant gains are made by buying and holding quality companies over time.

Enphase Energy (ENPH -1.75%), the iShares Global Clean Energy ETF (ICLN -0.29%), and Delta Air Lines (DAL -0.46%) stand out as three down-beaten stocks worth buying now. Three Motley Fool contributors were asked to explain why these three stocks are great picks for patient investors.

A person puts their hand on a solar panel during sunrise.

Image source: Getty Images.

It's time for forward-looking investors to warm up to Enphase Energy

Scott Levine (Enphase Energy): Shining brightly in investors' eyes, shares of Enphase Energy soared nearly 45% in 2022. This year, however, they haven't performed nearly as glowingly. Beginning the year on an inauspicious note, Enphase shares tumbled in January and have failed to recover, resulting in the stock falling nearly 20% year to date.

But this recent decline isn't indicative of something materially wrong with the company. In fact, Enphase is one of the leading options for investors looking to gain exposure to the burgeoning solar industry.

A leader in residential solar and energy storage solutions, Enphase is well positioned to prosper as the U.S. solar industry grows. According to the Solar Energy Industries Association, the U.S. installed solar capacity is expected to grow 400% over the next 10 years. And that's only stateside.

As of the end of 2022, Enphase Energy's products can be found in almost 150 countries, illustrating its opportunity to prosper from growth in foreign markets. In 2025, for example, Enphase pegs its serviceable addressable market at $23 billion.

Unlike some companies that are in the early innings of their growth and are not yet operating from a strong financial position, Enphase is on solid financial footing. Over the past five years, it has excelled at growing free cash flow.

ENPH Free Cash Flow Chart

ENPH Free Cash Flow data by YCharts.

This increased free cash flow afforded Enphase the ability to acquire companies without taking on excessive debt and jeopardizing its financial well-being.

For forward-looking investors who recognize that a stock's recent decline isn't necessarily reflective of its long-term growth potential, Enphase is a compelling consideration.

This clean energy ETF is nailing the trend

Daniel Foelber (iShares Global Clean Energy ETF): I'd like to piggyback off Scott's pitch on Enphase with the iShares Global Clean Energy ETF. Enphase is the fund's second-largest holding at a 7.6% weighting. And while I agree that Enphase stands out as one of the best growth stocks in the entire fund (if not the best), there are some major advantages to taking a diversified approach toward clean energy right now.

Managed by BlackRock with just a 0.4% expense ratio, this ETF provides a balanced way to buy the dip in renewable energy stocks. It also isn't overly concentrated in tech stocks. In fact, nearly 60% of the fund is in utilities and semiconductor stocks. And there are sizable holdings in pick-and-shovel companies that provide the electric components and equipment necessary to power a clean energy future.

Instead of choosing between a top stock like Enphase or an ETF, one approach is to build a foundation in an industry or sector you are interested in with a reputable ETF, and then add positions in high-conviction individual stocks.

The biggest risk of investing in a single clean energy stock is getting the trend right but the investment wrong. This is a common pitfall that has plagued many investors. For example, an investor could have accurately forecasted the dominance of mobile phones but missed Apple. Or the rise of electric vehicles but missed Tesla. Or the growth in e-commerce but missed Amazon. The list goes on and on.

The biggest advantage of choosing an ETF is that you have a higher chance of getting the trend correct. Sure, there will be plenty of individual stocks that crush the performance of the ETF. And I wouldn't be surprised if Enphase is one of them. But with at least a sliver of exposure to those outliers, an investor can reap the rewards of compound gains over time as well as offset losses in investments that don't pan out.

Delta Air Lines' management recently affirmed guidance

Lee Samaha (Delta Air Lines): Speaking at the recent JPMorgan Industrials Conference, Delta Air Lines CEO Ed Bastian told investors that the airline remains on track for its three-year plan laid out in December 2021. Moreover, "2022 performance was ahead of what we were planning in that three-year plan, and our 2023 targets and forecast and guidance is right in line, if not slightly better than we were thinking, and we're expecting 2024 to be the same," Bastian said.

That's music to the ears of Delta investors because, based on the numbers in the plan, Delta is a bargain basement stock. For example, management's guidance calls for a free cash flow of $2 billion in 2023 and $4 billion in 2024. For reference, Delta's current market cap is only $21.3 billion. So you can do the math on how much of its market cap in free cash flow the airline expects to generate over the next few years. 

Clearly, the market is worried that a sharp slowdown in air travel is coming, both from the consumer and the higher-margin corporate traveler. Meanwhile, based on Wall Street estimates, Delta's net debt is set to be $20.9 billion at the end of 2022.

All told, Delta's stock looks like it's priced to miss its 2023 and 2024 guidance, but as yet, there's no sign of a slowdown in air travel, and management remains bullish. As such, merely hitting guidance should lead to substantive upside for the stock. Here's hoping.