All Aboard the Stock-Market Solar Coaster

Solar stocks are sizzling—quite an accomplishment for the simplest and most mature of the green-energy technologies. Finding companies that could keep shining might require looking in less obvious places.

The MAC Global Solar Energy Index has generated a 233% return including dividends for dollar investors during the past year. That is well ahead of returns from wind-turbine makers Vestas and Siemens Gamesa, nevermind the S&P 500’s 15%.

As public and political support for green power has broadened, markets have come to expect a decadeslong renewables rollout. It is hard to see any catalyst for a change in sentiment, says Sam Arie, a veteran utilities analyst at UBS. Solar panels can be the cheapest way to generate electricity in many parts of the world. “In some cases it is even cheaper to build a new solar farm than run existing coal plants,” says Alex Monk, a portfolio manager at asset manager Schroders.

The catch is that the shift to renewables doesn’t guarantee shareholder returns. To justify high valuations, investors need to ensure companies have a defensible business as well as growth prospects.

Solar investors have already experienced at least two stomach-churning cycles. A key lesson has been that making panels themselves is a low-margin, hypercompetitive market best avoided. But other parts of the value chain offer better prospects.

For example, SolarEdge and Enphase make power inverters, which convert a solar panel’s power to alternating current and adjust performance to maximize output. Their Nasdaq-listed shares have returned 179% and 444% respectively during the past year and now trade for 72 and 93 times forward earnings. That is a lot of growth priced in. However, the technologies are patent-protected and could also be central to managing a smart home’s power between electric vehicles, solar panels, batteries and the like—a potentially vast market.

Developers are another option. They bid for, build and run solar farms. While installing the panels isn’t complex, experience is valuable when pricing bids and navigating the permitting process, and scale is crucial to sourcing panels effectively.

NextEra Energy, Enel and Iberdrola have built huge renewable-power farms as part of wider utility businesses and have ambitious rollout plans for solar and wind. Their shares have given investors total returns of between 16% and 28% over a year, and now change hands for between 15 and 32 times forward earnings. Barclays utilities analyst Dominic Nash credits part of the rise to general growth investors coming into the sector for the first time.

Then there are U.S. residential developers, which offer homeowners rooftop solar-panels paired with battery storage. The products provide added reliability, and monthly payments for the cost of batteries and solar panels that are often lower than existing utility bills. “It’s a pretty easy sale,” says Stephen Byrd, an analyst at Morgan Stanley.

Shares in SunPower and Sunrun, two such developers, trade at Tesla-type multiples, 118 times and 360 times forward earnings respectively. Revenues will grow—U.S. solar penetration will rise from 3% now to 14% by 2030, says Mr. Byrd—but margins will also come under pressure once installers compete head-to-head rather than with incumbent utilities.

Investors need to choose carefully as the stock-market solar coaster speeds up again. The general direction of travel may be up, but it likely still has plenty of twists and turns in store.

The U.S. and Chinese governments should take action to lower future borrowing, as a surge in their debts threatens to have “profound” effects on the global economy and the interest rates paid by other countries, the International Monetary Fund said Wednesday.

In its twice-yearly report on government borrowing, the Fund said many rich countries have adopted measures that will lead to a reduction in their debts relative to the size of their economies, although not to the levels seen before the Covid-19 pandemic.

However, that is not true of the U.S. and China, which will continue to see a surge in borrowing if current policies remain in place. The Fund projected that U.S. government debt relative to economic output will rise by 70% by 2053, while Chinese debt will more than double by the same year.

The Fund said both countries will lead a rise in global government debt to 98.8% of economic output in 2029 from 93.2% in 2023. The U.K. and Italy are among the other big contributors to that increase.

“The increase will be led by some large economies, for example, China, Italy, the United Kingdom, and the United States, which critically need to take policy action to address fundamental imbalances between spending and revenues,” the IMF said.

The IMF expects U.S. government debt to be 133.9% of annual gross domestic product in 2029, up from 122.1% in 2023. And it expects China’s debt to rise to 110.1% of GDP by the same year from 83.6%.

The Fund said there had been “large fiscal slippages” in the U.S. during 2023, with government spending exceeding revenues by 8.8% of GDP, up from 4.1% in the previous year. It expects the budget deficit to exceed 6% over the medium term.

That level of borrowing is slowing progress toward reducing inflation, the Fund said, and may also increase the interest rates paid by other governments.

“Loose US fiscal policy could make the last mile of disinflation harder to achieve while exacerbating the debt burden,” the Fund said. “Further, global interest rate spillovers could contribute to tighter financial conditions, increasing risks elsewhere.”

A series of weak auctions for U.S. Treasurys are stoking investors’ concerns that markets will struggle to absorb an incoming rush of government debt. The government is poised to sell another $386 billion or so of bonds in May—an onslaught that Wall Street expects to continue no matter who wins November’s presidential election.

While analysts don’t expect those sales to fail, a sharp rise in U.S. bond yields would likely have consequences for borrowers around the world. The IMF estimated that a rise of one percentage point in U.S. yields leads to a matching rise for developing economies and an increase of 90 basis points in other rich countries.

“Long-term government bond yields in the United States remain elevated and sensitive to inflation developments and monetary policy decisions,” the Fund said. “This could lead to volatile financing conditions in other economies.”

China’s budget deficit fell to 7.1% of GDP in 2023 from 7.5% the previous year, but the IMF projects a steady pickup from this year to 7.9% in 2029. It warned that a slowdown in the world’s second largest economy “exacerbated by unintended fiscal tightening” would likely weaken growth elsewhere, and reduce aid flows that have become a significant source of funding for governments in Africa and Latin America.

An unusually large number of elections is likely to push government borrowing higher this year, the Fund said. It estimates that 88 economies or economic areas are set for significant votes, and that budget deficits tend to be 0.3% of GDP higher in election years than in other years.

“What makes this year different is not only the confluence of elections, but the fact that they will happen amid higher demand for public spending,” the Fund said. “The bias toward higher spending is shared across the political spectrum, indicating substantial challenges in gathering support for consolidation in the years ahead, and particularly in a key election year like 2024.”

All Aboard the Stock-Market Solar Coaster

Much of the climb in solar stocks looks justified by growth prospects, but buyers may still be in for a bumpy ride

Says U.S. and China, which will continue to see a surge in borrowing if current policies remain in place.