Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of renewable energy company Advanced Energy Industries (Nasdaq: AEIS) fell 13% today after the company lowered second-quarter guidance.

So what: Management now expects second-quarter revenue to be $137 million to $140 million, down from a previous view of $148 million to $160 million. Earnings per share are expected to be at the bottom end of the previous range of $0.36 to $0.44.

Now what: Poor conditions in the solar market are to blame for the weaker than expected results, according to management. But the weak second quarter isn't expected to hurt the company's long-term strategy as it expects a falling levelized cost of energy to help results in the future. The weak second quarter shouldn't be a huge surprise to followers of renewable energy, so I see today's dip as a buying opportunity for shares.

Interested in more info on Advanced Energy Industries? Add it to your watchlist.

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.