Tesla's Solar Roof was unveiled way back in October 2016.

It's been roughly two years since Elon Musk unveiled the Solar Roof, but despite big promises, the company still struggles with the production of solar tiles.

According to research done by CNBC, there are not many installed Solar Roofs. "Several hundreds of homes with the Solar Roof on them" apparently turns out to be "scheduled for installation or partially installed".

Other reports were that delays are being caused by assembly-line problems at its factory, and moreover that products leaving the production facility are reportedly not up to the envisioned aesthetical standards.

All it means is that the Solar Roof is a harder nut to crack than expected. Delayed scale-up production could lead to higher costs and prices. At least for now we assume that the Solar Roof will not positively help the finances of the company.

"Elon Musk unveiled prototypes of Tesla's Solar Roof tiles In October 2016. They came in four styles that looked just like normal roofing material but were essentially miniaturized versions of traditional solar panels.The announcement helped Tesla justify its $2.6 billion acquisition of SolarCity one month later and represented Musk's vision for what the businesses could do together.

It's been almost two years since then. So where are the tiles?

"We now have several hundred homes with the Solar Roof on them, and that's going well. It takes a while to just confirm that the Solar Roof is going to last for 30 years and all the details work out," Musk said on Tesla's Q2 earnings call in August."