Tado, the German smart home startup that specializes in thermostats and more recently moved into flexible “time of use” energy tariffs based on loadshifting technology, is today announcing the next step in its life as a business. It’s going public by way of a SPAC deal.

GFJ ESG Acquisition, a German SPAC entity focused specifically on sustainable technologies, said it will combine with tado and list the new company on the Frankfurt exchange. GFJ and tado are now working on the PIPE transaction, which when completed is expected to value tado at €450 million ($514 million at today’s rates). The new business will continue to trade as tado.

A spokesperson for tado said it is not disclosing how much it plans to raise in the listing, nor when the listing is expected to happen.

The move comes swiftly on the heels of two big developments for tado. Last week, tado acquired aWATTar (yes that is how the company styles its name…) to expand from energy consumption hardware inside the home, to software to better manage energy consumption and costs based both on how the customer uses energy, and how pricing varies depending on the fluctuations of that energy source (which can include renewable sources like solar and wind, as well as more traditional channels).

Also, in May, tado raised $46 million. At the time, the company said this would be its last round before a listing, and that’s what is playing out now. Altogether the company had raised just shy of $159 million, with an impressive list of investors, including Amazon, Siemens and Telefonica. Its valuation in those private rounds was considerably lower than the €450 million it expects to achieve with its market cap at listing: it was around $255 million according to PitchBook data.

The deal is notable because it will be one of the first big green tech startups in Europe to go public. Tado’s bigger goal is to build services to help manage energy use in and end-to-end system, starting at the power grid and terminating with consumers, in their homes. That business has taken two different turns so far. It first started as a maker of smart thermostats, and business that has now sold some 2 million devices. Then, tado diversified into energy tariff and managing use is catapulting the company into a wider business based on big data, predictive analytics and harnessing the wider and very fragmented markets of renewable energy and energy hardware systems.

The company today says that it has sold more than 2 million smart thermostats, and its energy-management technology connects some 400,000 buildings and households in 20 countries, with more than 7 gigawatts of energy capacity under management. Its works with some 18,000 systems from 900 OEMs, and claims that customers using its load-balancing technology save an average of 22% on heating costs annually.

As concerns about climate change continue to become ever-more urgent, and services for consumers to make choices to reduce greenhouse emissions become more readily available and affordable, a new window of opportunity has opened up for green tech and clean tech companies. This listing underscores how one of them feels now confident enough in that traction to make the leap into being publicly traded to grow further.

“The entire team at tado is extremely proud to partner up with GFJ,” said Toon Bouten, CEO of tado, in a statement. “We share the same convictions and the same passion for environmental technologies. And we are determined to jointly help our customers save money and reduce their ecological footprint. Together, we are in a great position to create a more sustainable energy future.”

When the deal is closed, Bouten will step down as the head of the company, with Oliver Kaltner (who lists his current role as President of office solutions provider Room) will be taking on a role as CEO, with Christian Deilmann as CPO and Johannes Schwarz as CTO. Emanuel Eibach will remain CFO. Gisbert Rühl shall become chairman of the supervisory board. Josef Brunner, Petr Míkovec, Toon Bouten and Maximilian Mayer shall also join the supervisory board.

“Both GFJ and tado are determined to turn up the heat on fighting against climate change in a smart way. tado already is a market leader in the very spirit of a new wave of green tech companies,” added Gisbert Rühl, CEO of GFJ. “We are excited to bring in capital and expertise to help them grow even stronger and foster their technology development. Around 21% of energy consumption in the EU is used for heating and cooling private housing alone. If the EU and Germany want to fulfil their commitment to becoming the world’s first climate-neutral economy by 2050, there is no alternative to decarbonising the housing sector.”

tado, as a public business, will gain a new level of transparency to the market, which will be good for the wider green tech industry as a whole. For now, the company is projecting that it will be making more than €500 million in annual revenues in three years, by 2025.