Some Americans still dislike the appearance of solar panels, according to Kate Collardson, who handles operations for Solar Service of Colorado, a solar maintenance and inspection company.
For people who object to the look of standard panels, a solar roof offers an alternative: tiles or shingles that house solar cells but closely resemble regular tiles. The appearance argument matters especially for historic buildings, where heritage rules restrict changes to their exteriors.
The product category drew wide attention in August, when Tesla’s website stopped offering solar roofs. The BBC reported that the move followed disappointing sales and a lawsuit over sudden price increases. Several other companies have also exited the market, but Tesla’s decision sent shockwaves through the solar roof industry, the article states. Some observers see it as a death knell for solar tiles; others see an opportunity.
Deborah Learoyd, CEO and managing director of the Swiss company Freesuns, said the firm is considering expanding to the US. She estimates that the company’s sales have grown 20-30% since it was established in 2019.
Solar roof components are still produced in smaller batches, which limits economies of scale and standardisation, though flexible manufacturing could help somewhat, according to the article. Learoyd said unit costs for Freesuns products are slowly decreasing, but “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 added time and paperwork can hurt a roofing business, Collardson explained. “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’.”
Collardson charges more to repair solar shingles than a standard photovoltaic (PV) setup. With traditional solar, she said, “we generally have electronics on the panel and a map that shows us exactly how much each panel is producing”, making faults easy to locate. “With solar shingles, we don’t really have the benefit of that mapping; there’s no room underneath the shingle for the electronics.” Thermal cameras can identify trouble spots, but accessing them creates another problem: “You can remove the one in the middle of the array, but you have to walk on the others, and you really shouldn’t walk on them because you’re going to create micro-fractures and that’s going to cause issues down the road.”
Before repair costs are counted, a solar roof might cost twice as much as a system of solar panels mounted on a roof, the article says.
Solar roofs are also less efficient. One reason is that the tiles are smaller. Another is heat loss: because the tiles sit close to the roof, there is less airflow than with standard panels, and heat impairs solar performance. Coloured tiles are less efficient still, according to Ben Graves, co-founder of UK solar company Sunsave. “The reason why all solar cells are black, and increasingly the whole panel is now black, is because black is the best absorbing colour,” he said. Overall, far more space would need to be devoted to solar roof tiles to produce the same amount of energy.
Sunsave does not offer solar roofs. “Most people in the UK just don’t have enough money to pay for it,” Graves said. Appearance was a bigger factor five years ago, but now “the vast majority of consumers are most interested in how much they can save”.
Supporters argue solar roofs should not be measured against standard modules. “Let’s not compare PV roof tiles to a standard PV system, but look at PV roof tiles as generating additional electricity from our roofs instead of just having the roof sit there,” said Martin Heinrich, who leads a research group at the Fraunhofer Institute for Solar Energy Systems in Germany.
While standard solar panels have advanced steadily, solar roofs have not kept pace. Matrix shingling technology could help. The method cuts solar cells into narrow strips, layers them like overlapping shingles and connects them with electrically conductive adhesive instead of metal wires, allowing current to flow around shaded areas. “If you get like a bird pooping on a part of the cell, the current can go around it,” Learoyd said. The approach also boosts energy output and improves appearance by hiding silver wires. Heinrich noted another benefit: “since we cut the cells into smaller areas, we can fill out special sizes more easily. You don’t have to adhere to the regular pattern size.”
Freesuns is an early adopter of matrix shingling in building-integrated PV. “We see it as a big opportunity for the future in terms of how we would make our tiles,” Learoyd said. The company would also benefit from better software for automated design, which would speed a process in which each roofing job is unique. Learoyd believes that would lower costs and give “the whole construction industry much more confidence in using the product”.
Ten years after her own solar roof was installed, Learoyd remains optimistic despite the sector’s setbacks. She believes that, for people with the means, it will eventually become standard to install a new roof with embedded solar. “It’s just a no-brainer.”
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