NEW YORK (TheStreet) -- Shares of Vivint Solar (VSLR) - Get Report have had a rough ride since its initial public offering in October. The stock is down 28% from its $16 IPO, currently trading at $11.46. 

However, that's not stopping CEO Greg Butterfield from being optimistic. He cited the company's most recent earnings results on March 4, when the company topped EPS and revenue expectations. Sales soared 248% year over year. 

The company had a net loss in 2014 and is expected to have another one in 2015, according to analysts. But Butterfield pointed out that Vivent's cost per watt, or how much it costs the company to generate one watt of electricity, is falling. At the beginning of 2014, the company's cost per watt stood at $4.25, but fell an astonishing 30% to $2.96 in the fourth quarter. 

For 2015, Butterfield said he expects that cost to fall into the range of $2.80 to $2.90. 

Vivint Solar VSLR data by YCharts

Cutting expenses alone won't get a company to profitability. But revenue should continue to grow at a rapid pace, given the large addressable market of residential solar. 

Vivint Solar is one of the fastest-growing companies in this segment, he said, explaining that as a whole, residential solar has plenty of room to grow. Consumers want choices when it comes to solar and that's why utility companies are being met with opposition when attempting to levy fees against consumers who add solar units to their home.