Why are more roofs not made of solar tiles?

Some people in the US "still hate the look of solar", Kate Collardson acknowledges.

She would know. Collardson handles operations for the Solar Service of Colorado, a solar maintenance and inspection company. She's also held just about every other job in the industry, from installer to instructor.

For those that hate the look of solar panels, an alternative is a solar roof, where the tiles (or shingles) house solar cells, but look much the same as regular tiles.

This is especially important for historic buildings, where heritage rules limit changes to their appearance.

For many people, the first time they'd heard of this product category was in August, when Tesla's website stopped offering solar roofs, external. This followed disappointing sales and a lawsuit over sudden price hikes, external.

Other companies have also pulled out, but Tesla's decision in particular sent shockwaves through the solar roof industry.

For instance, the small Swiss company Freesuns is considering expanding to the US.

Deborah Learoyd, Freesuns' CEO and managing director, estimates that the company's sales have grown 20–30% since it was established in 2019.

In general, solar roof components continue to be manufactured in smaller batches. This limits the economies of scale and standardisation, though flexible manufacturing could help somewhat.

Learoyd says that while the unit costs for Freesuns' products are slowly decreasing, "a lot of the cost is actually the fact that every roof is a little bit different. And so it has to be engineered a little bit differently, installed a little bit differently".

Solar roofs typically require collaboration among roofers, solar installers and electricians. And building regulations tend to be more complex than for solar panels.

The additional time and paperwork can take a toll on a roofing business, Collardson explains. "You try to put a roofer into the equation and they're going, 'This is taking forever. I'm losing money. I could have sold 10 roofing jobs in the time that it takes me to sell this one'."