This article is part of our Rising Star Portfolio series.

Only on extremely rare occasions will I advocate a "take the money and run" approach to my Rising Stars portfolio. Today marks one such moment. As an investor, I think it's important to avoid getting locked into your own thinking, and realize there can, and probably should, be an exception to every rule we try to hold ourselves to. To that end, I've decided to bid solar stock SunPower (Nasdaq: SPWRA) a relatively quick adieu.

Any time now, French energy giant Total (NYSE: TOT) is expected to complete its purchase of a majority stake in SunPower, which could be a great boon to this renewable energy company. However, let's not forget that Total's interest is a major reason why SunPower's stock price has surged by about 50% since my January purchase.

In May, SunPower shareholder Smorgasbord1 posed the "sell or hold" question on my discussion board. My knee-jerk reaction was to hold, but after slowly mulling that dilemma, I've finally concluded that selling is in order.

I don't intend my decision as a comment on SunPower's long-term future or its products. It simply reflects my sense that Total's involvement adds uncertainty. An established corporate majority shareholder with plenty of resources can be a boon to a company in a nascent or highly competitive field, and it really might prove to be a huge help to SunPower's competitive position. However, I can't help wondering whether it could also end up being a distraction and hindrance to growth in the future.

There's still also a great deal of uncertainty surrounding two major solar markets, Italy and Germany. Rival First Solar (Nasdaq: FSLR) said earlier this week that it's experienced a slight recovery in the Italian market. However, SunPower offered up disappointing profit guidance, discussing changes in Italy and announcing that it's switching to lower-margin residential and commercial markets in Europe.

I plan to stick by the lion's share of my Rising Stars stock purchases through thick and thin, but in this exceptional case, I've decided that this major gain in SunPower's price is simply too nice to pass up, given the surrounding uncertainty. Investors like me can probably find better opportunities elsewhere.

Going forward, I plan to look for more renewable energy stocks to purchase. There are lots of interesting, exciting, potentially blockbuster stocks to consider in the alternative energy realm; biofuels companies Solazyme (Nasdaq: SZYM), Gevo (Nasdaq: GEVO), and Amyris (Nasdaq: AMRS) have all recently gone public with great fanfare and investor interest.

Do you have any favorites in the renewable energy field that you think I should consider for this portfolio? Do you think it's a mistake to ditch SunPower now? Let your thoughts shine in the comments box below.