Solar Rises as Global Energy Opportunity

And at an auction in the U.K., developers won contracts to build five solar plants that will produce power at just a tad more than the current going rate for conventionally generated electricity.

And if none of those developments are adventurous enough, the Solar Impulse 2, a solar-powered aircraft, took off on the beginning of a flight around the world expected to take five months as it campaigns for clean technologies. The Solar Impulse 2 counts among its roster of sponsors not only Zurich-based ABB Ltd., which is the largest maker of devices that convert solar energy into electricity, and Masdar, Abu Dhabi's state investment company Mubadala's renewables unit.

According to Richardson, the countries offering the most potential for solar growth and installed capacity over the next few years, in order, are China, the U.S. and India. China and India, he said, are driven by government initiatives to reduce air pollution and the costs of energy on the economy. In the U.S., he said, it's a similar situation, but without the same drivers to control air pollution. However, he said, "greenhouse gas will certainly be a driver as we approach climate negotiations in Paris at the end of the year."

Richardson said that Impax also expects to see, within the next five years, "some tax on carbon, whether that's a global tax or country by country. We expect that to help drive the growth in renewables, certainly in the U.S. and definitely in China and India. And with that continued growth, another thing happens: so-called grid parity [when an alternate energy source can generate power at a cost less than or equal to the cost of power from the grid], particularly with solar. Once that happens in enough markets, it makes sense to put it everywhere." That will beget further declines in costs, and this sort of snowballs."

Not that investors should regard solar as a get-rich-quick scheme. In fact, Richardson said, "I think it's hard to invest in solar projects themselves." Second derivative approaches, such as investing in original equipment manufacturers that make solar panels, do provide a lot of opportunities, he said, as do "third derivative opportunities—companies that make equipment that the solar manufacturers need in their own factories."

Some areas where solar isn't faring too well are Japan, where Richardson said there are short-term disruptions because "utility companies have put the brakes on connecting solar projects to the grid," and Russia, where recent reports have identified solar projects' problems with a plummeting ruble. A first-ever move in 2013 by the Russian government to provide subsidies for renewable projects has not been enough to counteract the effects of the ruble's fall, a tanking economy and higher interest rates—all of which have combined to drive solar companies to seek renegotiation of the terms of their contracts.

Richardson said, "The issue is [that solar development is] not always just a straight line. There are some hairpins along the way that are hard to see right now. It's the same with any business; it's not perfectly rosy. Solar stocks, for instance, are pretty volatile, high-beta names. If you're an investor, you need to be long-term and forget about it, or be really active and really close to it if you're going to be buying and selling; otherwise, you run the risk of buying low and selling high because of volatility."

Still, if current trends are any indication, the sun is definitely rising on solar.