Mobile, pre-fab and sustainable – that's what the modern dwelling needs to be, says a Spanish start-up named as an EIT Awards finalist by KIC InnoEnergy

Anna Jenkinson, Science|Business

Rosa Vilarasau was approaching her 40th birthday when she decided she had had enough of working for a Spanish confectionary company. "If I'm going to do something on my own, it has to be now," she recalls thinking to herself.

So she contacted a university friend, Pol Guiu, and they started throwing venture ideas around. They finally hit on one that chimed with them both: designing the perfect 21st century house. What's that? In their view, it's a sustainable, mobile home.

"You evolve as a person, but your home doesn't evolve with you," Vilarasau said, explaining how they wanted to free the home from the land and allow it to adapt to its owners' new job in a new city or a new addition to the family. "Technology allows this solution to be possible," said Vilarasau, who with Guiu founded the company Think CO2 in December 2009.

The company's basic concept is an energy-efficient, pre-fabricated, modular house. Being a passive house, it uses minimal energy for heating or cooling the space: "This is the magic of it. You can run the house with almost nothing," said Vilarasau. Being pre-fabricated, it can be put up in four or five days and taken down in a couple of days if it needs to be moved to a new plot. Being modular, it can be expanded if a bigger space is needed. In general, a "noem" (no emissions) home can be between 30 and 90 square metres; it can stand alone or be an annex for a growing family or grandparents. The price range per square metre is €1,600 to €2,000.

We have proved that once you put know-how and passion together, you can make it happen, said Vilarasau

The main structural material is solid pinewood from the nearby Pyrenees. In order to keep Think CO2's carbon footprint to a minimum, the target market is Spain, Portugal, Andorra and France. In the future, Vilarasau would like to take the concept to the Alps, using local wood from the Alpine region. As well as residential buildings, other possible uses are ski resort accommodation and eco-luxury hotels, she noted.

A milestone for the company was presenting its prototype, which is now used as Think CO2's office, at Solar Decathlon 2010 in Madrid. The years of development started to become reality, Vilarasau said.

Since then, the company has secured its first customer: a 74-square metre project for a family near Valencia. The customer approached Think CO2 in spring 2011, explaining how their second residence was no longer big enough with the arrival of a grandchild; they wanted a green solution and one that could be built by the summer. The Think CO2 team designed the house to the customer's specifications within 10 weeks and built it in five days. "It was fantastic," Vilarasau enthused. "The truck arrived on the Friday at 4pm and by the end of the day the first module was in place." Over the next few days, the different components were slotted into place and the dream became reality.

Read more about this finalist: The Finalists - Just the Facts