Inside a German factory, robots assemble molded panels to precisely fit the walls of an old building like a second skin, with built-in insulation designed to help the building dramatically reduce its energy consumption . It is part of a system to solve one of the challenges of transitioning to a net zero world: with so many outdated and inefficient buildings, which are a major source of global climate emissions, the traditional renovation process is extremely slow.

According to one estimate, at the current rate of renovation in Europe, it would take 500 years to completely decarbonize every existing building. (The United States is probably moving even slower.) To avoid the worst impacts of climate change, the world must reach net zero no later than 2050, which means that the world’s existing building stock must be transformed into less than three decades.

[Photo: courtesy Ecoworks]

Ecoworks, the German startup behind the new system, starts by taking a 3D scan of an old building, inside and out, creating a digital twin of the structure. “If you have a digital twin, you can actually automate planning, which in a normal renovation would take months and lots of engineers and architects,” says founder Emanuel Heisenberg. Plans can be sent to its suppliers and to a factory, where almost everything is built in advance; each panel includes windows, ventilation and channels for pipes. A modular roof has integrated solar panels. On site, construction workers can install a facade panel in as little as 20 minutes. Converting an entire building, including replacing fossil fuel heating, can be done in weeks, compared to the months or years required in a project using traditional construction.

Heisenberg, a renewable energy entrepreneur, was inspired by a similar system for building renovations in the Netherlands. He shared the idea with several construction companies, but none wanted to change the status quo. (Industry doesn’t embrace innovation, he says.) “At the heart of the problem, the construction industry invests less than 1% in R&D,” he says. So he decided to start a business himself, developing a process that would be as automated as possible.

[Photo: courtesy Ecoworks]

Over the past year, the start-up has been tracking energy consumption trends on one of its earliest projects: a 1930s apartment complex in a small German town. Before the renovation, the 12-unit building consumed 450 kilowatt hours of energy per square meter, making it one of the least efficient buildings in the country. Now the building actually produces additional energy which it feeds into the grid. “After the renovation, we have negative emissions,” says Heisenberg. Because the new facade is made of wood and the trees capture carbon as they grow – and because the project reuses most of the old building instead of building from scratch – the project also has a low carbon footprint of construction. Within two years, Heisenberg expects the building to have fully offset the construction footprint, including the emissions from making the solar panels.

[Photo: courtesy Ecoworks]

The company is currently working on seven new projects which it will begin installing this summer. But he also wants to go on a much larger scale. In Germany alone, according to the German Energy Agency, more than 30 million apartments will need to be renovated over the next 25 years. A new European law that could soon be adopted will require the least efficient buildings to be renovated over the next five years. Technology is not the only challenge; Heisenberg is also trying to work with the government to create standardized building codes. (As in the United States, codes vary by location.) Financing is less difficult since Germany offers grants for part of the cost of the renovation and subsidized loans to cover the rest.

[Photo: courtesy Ecoworks]

The startup uses AI to identify buildings that best suit its approach. It is easier to work with simple apartment complexes in the form of blocks. But he plans to later expand to schools and eventually single-family homes, and start working in other countries. There’s no way to meet the global challenge in time, Heisenberg says, without moving away from traditional construction. “You really need technology to solve this problem.”