Elon Musk isn't used to not winning.

He was the founder of PayPal, the online financial payment platform that squashed dot-com and banking giants that wanted in on the action. PayPal is now eBay's (NASDAQ:EBAY) fastest growing subsidiary.

Musk then went on to usher in the modern era of electric cars with the high-end Tesla Roadster. Tesla Motors (NASDAQ:TSLA) hasn't sold a lot of cars, but it's been a hit with investors. Tesla shares have more than doubled since going public at $17 two years ago.

Now he's championing another green energy cause with today's publicly traded debut of SolarCity (Nasdaq: SCTY).

SolarCity was initially set to go public between $13 and $15, but ultimately had to settle for a sobering price of $8. It did bump the number of shares being offered to 11.5 million, but that's not much of a consolation prize.

The stock opened at $9.25 and quickly moved above $10. The pop may be welcome, but it's a far cry from what Musk -- SolarCity's chairman -- and his cronies were originally hoping to see.

SolarCity gives homeowners and businesses a cost-effective way to go solar. SolarCity is a one-stop shop, offering everything from the initial permitting and installation to the ongoing maintenance. The company's claim that solar energy is cheaper than oil or gas is valid, but the upfront cost of solar panels has always been the rub. There are government subsidies and tax credits that encourage going solar, but those incentives may very well be on the way out in the coming years as austerity measures kick in. SolarCity spreads out the initial costs over time for customers by financing the installations, and the drop in solar panel prices -- something that has slammed the leading solar energy stocks -- actually works to SolarCity's advantage by making its service more cost-effective.

Solar itself has been out of favor for some time, but sentiment is starting to bounce back. Susquehanna boosted its price target on industry bellwether First Solar (NASDAQ:FSLR) this week, even though the shares have nearly tripled since bottoming out in June.

SolarCity's growing in popularity. Revenue soared 139% last year, and it has more than doubled through the first nine months of 2012. The challenge here has been profitability, or in SolarCity's case the lack of it. The company has been posting net losses that have been increasing every year.

However, Musk's name -- and SolarCity's marketing approach to spread payments out over 20 years -- will make SolarCity one of the more magnetic names in solar.

Sooner or later, though, profitability is going to have to show up to brighten the stock's otherwise sunny fundamentals.

Longtime Fool contributor Rick Aristotle Munarriz has no positions in the stocks mentioned above. The Motley Fool owns shares of Tesla Motors. Motley Fool newsletter services recommend eBay, First Solar, and Tesla Motors . 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.