Go to Google Finance and type NRGY into the quote box. Go down to the lower right corner and click on the company website link. Check the ex-dividend and record date info there. As long as you are there, look for other news items.
It is really important to go to the authoritative source for dividend info which is the company website. The risk with NRGY is that recent events may adversely impact the dividend. I'm long NRGY and don't think that will happen, but I am not always right.