What happened 

Shares of microinverter manufacturer Enphase Energy Inc (ENPH 2.09%) jumped as much as 14.8% in trading Thursday after announcing a new residential solar partner. Shares settled down somewhat late in the day but were still up 8.8% at 3:40 p.m. EDT. 

So what

Enphase and Sunpro Solar, who was ranked the 11th biggest residential solar provider in the U.S., announced an exclusive supply agreement. Enphase will be Sunpro's exclusive inverter supplier, adding another big customer for the company's microinverter solutions. 

Large roof with solar panels.

Image source: Getty Images.

Sunpro's CEO Marc Jones said he was excited about Enphase's roadmap and thinks next-generation inverters will allow for inexpensive transitions between grid-ties and off-grid operation of solar systems. 

Now what

Adding the 11th largest residential solar installer to the portfolio may not sound like a big deal, but every customer adds to Enphase Energy's scale. Another encouraging sign is customers being excited about Enphase's eighth-generation inverters, which will help incorporate solar as well as energy storage in the home. I don't think this announcement alone is a great reason to buy the stock, but along with positive news like a partnership with SunPower and growing sales, Enphase Energy looks to be on the right track in 2018.