Walking up stairs in the school, I trigger another innovation into action: Dutch-owned Philips is trying out its new sound- and motion-sensitive lights, which default to off unless the switch hears or feels someone approach. Buildings will have smart controls, automatically raising and lowering window blinds to regulate light and temperature, for example. Other innovations include a pneumatic municipal waste collection system, produced by the Swedish company Envac, which will eliminate the need for refuse trucks, and the authorities will be allowing General Motors to road-test the next-generation of its driverless EN-V (Electric Networked-Vehicle) cars.
In March, the first 60 families moved into the city's residential buildings, all of which are designed to a minimum green buildings standard, including water-saving sanitary fittings, insulated walls and double-glazed windows, as well as a south-facing orientation to optimise passive heat. Such techniques may be standard in some countries, but in China they are rare.
Also rare here is the emphasis on liveability. Parks and green spaces are planned around the city, and reed beds have been created to attract birdlife and help clean the water. Lanes and alleyways have been strung through the usual grid layout of big blocks, meaning communities can develop. Everywhere is walkable or cycle-able, so that people do not feel socially excluded from areas. Free recreation facilities will be provided within 500m (1,640ft) walk of anywhere.
A green spine, called the “eco valley” runs through the heart of the city with cycle routes and a tram. Residents will be encouraged to use regular low-carbon transport or walk, rather than driving. Cars won't be banned, Ho says. "We don't want to create obstacles for people, but rather make it conducive to use alternatives." Niche designs that have focused blindly on eco-technologies have not worked, he says. "This eco-city will be practical – it will work."
To that end, the city is setting itself up as a hub for green tech enterprise and creative industries. Six hundred companies have already set up shop, including an animation studio that is powered by its own energy station, incorporating solar PV walls as well as roof panels.
Water provision is one of the bigger challenges in this naturally arid area. Tap water will be drinkable and piped in, although the city is planning a possible desalination plant too. A lot of effort is being put into conserving water and recycling it for irrigation and toilet flushing. "The lakes and water pipes have been lined in clay or concrete to prevent salt water incursion, and all waste water is being sent to plant for anaerobic biodigestion," says Ary de Koning of the EU-China River Basin Management Programme, who is advising the city on water issues. "The methane emitted in the digestion process is then used to produce energy," he says.
It certainly feels like a more pleasant place to live than the traffic choked, polluted cities further inland, even at this incomplete stage. And unlike the majority of planned ecocities, this one will actually be finished and already has residents. But whether it lives up to its green credentials will depend in part on the type of society it nurtures.
It strikes me that social inclusivity is perhaps Tianjin’s most novel and important mission. One fifth of the housing will be subsidised for low-wage workers and their families. "We want to avoid the idea that this is a haven for rich people or second-homers from Beijing," says Ho. "Being green isn't a luxury, it's an affordable necessity. This city should be a practical, replicable, scalable model for elsewhere in China and the world."