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Estonia’s CleanTech company Solarstone produces one of a kind solar roofs

Solar panels on the roofs can be aesthetic to look at for the naked eye – three guys, the founders of Estonian CleanTech startup Solarstone, figured out how this can be done.

When Solarstone started in 2015, the solar panel market was essentially mature, innovation was driven by materials science, but there were limited possibilities for the application of solar panels. Existing solar solutions available on the market were either too expensive or unfit for various reasons, mainly poor aesthetic appeal. This created an immediate understanding by three Solarstone founders Mait Kukk, Silver Aednik, and Mattis Jürimäe that they need to start building-integrated solar panels that simultaneously act as a roofing material. These materials are called building-integrated photovoltaics (BIPV). Unlike traditional solar panels, Solarstone products do not need a conventional roof underneath.

Seven years later, Solarstone’s production has grown from tailor-made roofs to mass production of about a thousand roofs per year. The production volume grew significantly some years ago thanks to partnering up with Sunly, also an Estonian-founded company and one of the most progressive renewable energy investors in Europe, which introduces a unique product in solar panel roofing. Their first of its kind product is called Click-on, which makes it possible to render essentially any solar panel into 2-in-1 weatherproof roofing material without any additional sublayer. Click-on is universal and can be used for residential and commercial roofs as well as solar halls, carports, and facades. Click-on panels have won a Quality Innovation Awards prize in circular economy and carbon neutrality subsection – a global competition among the most ambitious innovators around the world. And they are not shy to talk about further ambitions. As Solarstone is one of the leading building-integrated solar providers in the Nordics today, their goal is to reach the top three in the world by 2025 in the rooftop segment. Unique and scalable solutions, combined with energy efficiency regulations and the Green Deal, are paving the way for a greener future.

Although having its main export markets in Scandinavia and currently starting exporting to the US, UK, and Germany, all the production and innovation is happening in the small Southern-Estonian town of Viljandi. „All three Solarstone founders were either living in Viljandi or had a very close relation to this town, hence the decision was born to also kickstart the business in here and build lasting roofing systems that look pleasant to the naked eye,” Silver Aednik, company’s managing director and co-founder says.

Solarstone’s factory in Viljandi is located on an area of 1,200 sqm, where anyone can pay a visit (with prior notice) and get acquainted with the product range. „With today’s setup, we can produce 20,000 tile interlocking solar modules per year, resulting in approximately 715 design solar roofs and 25,000 Click-on kits. That means just about 1,000 economical solar roofs per year,” Aednik notes.

For a reader more familiar with Estonian innovative companies, it is not the first time that Viljandi as a location has come up. Cleveron, a developer of innovative parcel lockers and robots is also headquartered there and doing business with some of the largest companies in the world. Asso Uibo, Invest Estonia’s director of regional business development in South Estonia, says that the local community of Viljandi really welcomes new investments – there is a whole ecosystem for servicing new companies and helping them with whatever they might need.

“The local industrial sector is particularly strong. Viljandi County’s added value in the metal and equipment industry is over 150% higher than the Estonian average. There are more skilled workers and vocational schools here. The proximity of the Viljandi Culture Academy also provides an important advantage, through which it is possible to find, for example, craftsmen or product designers. Viljandi is a very attractive living environment where people like to live and where it is easy to relocate for people from outside.”

Solarstone’s business partner Sunly saw great potential in Solarstone’s team and product already in 2019. „Solarstone was our first investment and it motivated us to help other startups disrupt the field of electrification,” Rasmus Udde, investment lead at Sunly says. „The solar roofing market is growing rapidly due to growing climate and energy security problems. In the future, we believe that every house and building may be its own mini power plant with the roof as the central hub. This makes us confident that Solarstone has immense potential as it grows its team and expands into Europe,” Udde confirms.

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