The COVID-19 outbreak has upended the global economy, causing stocks to plummet. Investors are selling off everything due to the uncertainty of when conditions will stabilize and we'll return to some sense of normal.

While market conditions could get worse before they eventually improve, investors with a long-term outlook could have a rare opportunity to buy high-quality companies at attractive values. One sector where that's the case is renewable energy. Three stocks that stand out as the top buys right now are Brookfield Renewable Partners (BEP 1.92%)First Solar (FSLR 2.70%), and NextEra Energy (NEE 0.04%).

A field of solar panels with wind turbines in the background at dawn.

Image source: Getty Images.

Getting bigger and better

Brookfield Renewable entered this downturn from a position of strength, boasting one of the best balance sheets in the renewable energy sector. Because of that, it's been able to remain on the offensive. It did that by recently sealing a deal to acquire the rest of fellow renewable energy producer TerraForm Power that it didn't already own.

That transaction will create one of the largest renewable power companies in the world while enhancing its financial profile and long-term growth prospects. That positions it to continue creating value for investors over the long term. In Brookfield's view, it can grow its cash flow per share by 9% to 16% per year through 2024. It has high confidence in that view since long-term, fixed-rate contracts back the bulk of its cash flow.

Those growing cash flows, meanwhile, should support the company's ability to increase its dividend -- which recently yielded more than 6% following a roughly 40% decline in its value from this year's peak -- by an annual rate of 5% to 9%. That combination of yield and growth makes Brookfield look like a great long-term buy, especially when adding in the potential for a rebound in its value as market conditions improve.

The cash to weather any storm

Shares of solar-panel maker First Solar have lost more than 50% of their value from the peak earlier this year due to the stock market sell-off. While the company reported lackluster fourth-quarter results and 2020 guidance last month, its long-term outlook looks bright.

It's already sold out about 90% of its manufacturing capacity this year and has contracts in place for roughly two-thirds of the panels it can make next year, thanks to strong demand for solar modules. That red-hot demand should continue, given the expectation that solar energy development will accelerate in the coming years. While the economic slowdown due to the COVID-19 outbreak might dim that forecast a bit, the long-term outlook for solar energy remains bright as the global economy continues to pivot away from fossil fuels.

Meanwhile, First Solar complements its growth prospects with one of the best balance sheets in the solar-panel manufacturing sector, which includes more than $1.3 billion in cash. To put that cash balance into perspective, it's about one-third of First Solar's entire market capitalization following its stock-price plunge. That gives it the financial flexibility to weather any storm while providing it with the funds to create value for investors in the coming years.

As recession-resistant a business as they come

NextEra Energy generates very predictable cash flow because it sells the power it produces under rate-regulated structures and long-term, fixed-rate contracts. Meanwhile, demand for electricity tends to be relatively stable, even during a recession. While this one will be different because the COVID-19 outbreak is shutting down lots of commercial and industrial businesses, it should be a temporary issue.

Meanwhile, NextEra Energy has the financial flexibility to weather this storm because it has one of the best balance sheets among the large electric utilities. That will allow it to continue investing in opportunities that will power growth in the coming years.

One of the company's biggest growth drivers is its renewable energy business, which has a large backlog of commercially secured projects. These expansion-focused investments should support earnings growth of 6% to 8% per year through 2022. Meanwhile, thanks to its below-average dividend payout ratio, NextEra believes it can increase its dividend by around 10% annually through at least 2022. That positions the company to continue growing shareholder value in the coming years.

Keeping the long-term view in mind

It's unclear how much impact the COVID-19 outbreak will have on the economy in the near term. That uncertainty is weighing on stocks, including those of top-notch renewable energy companies like Brookfield Renewable, First Solar, and NextEra.

While many companies will struggle over the coming weeks and months, that trio can weather this storm thanks to their contract profiles and strong balance sheets. Because of that, they have the financial flexibility to continue investing in the sector, which has a bright future due to the economy's transition to cleaner fuel sources. As a result, these companies all look like excellent buys right now for investors who have a long-term mindset.