pg 25 – The team devised innovative techniques to ensure the conservatory air conditioning remained carbon-neutral, winning RIBA’s 2013 Lubetkin Prize
pg 26 – From the outset, the project’s greatest challenges were to deal with the balance between the daylight required for the plants to flourish and the intense solar gain on the equator, while finding a way to cool and dehumidify Singapore’s hot and humid air for the domes
without imposing a large carbon footprint.
pg 26 – The UK is known internationally for its expertise in reproducing environments for non-native plant species to grow, such as in London’s Kew Gardens and the Eden Project in Cornwall. But while those projects keep hothouse plants warm in a cool climate, it was a
greater challenge to cool plants in a subtropical climate in an energy‑efficient manner.
pg 26 – Part of the answer was in the creation of the garden’s most distinctive features – the concrete-cored, steel-clad ‘Supertrees’, some nearly 50m tall. Covered in plants, these structures provide sustainable energy while simultaneously providing the infrastructure supporting the site’s enormous climate‑controlled conservatories
pg 27 – It chose Grant Associates of Bath to lead the £350 million Bay South project, Wilkinson Eyre as the principal architects and Atelier One and Atelier Ten – both based in London – serving as, respectively, the structural engineers and the environmental and building
pg 27 – harness solar power to provide the energy needed to cool and dehumidify Singapore’s hot and humid air. But Singapore, although hot, is also very cloudy, reducing efficiency for most of the day and potentially overstressing the system when the sun does
pg 27 – NParks was maintaining and pruning several million trees in metropolitan Singapore, including sending tonnes of tree cuttings a week out of the city, mostly to landfill or for incineration. So a 7.2MW biomass boiler was developed to burn the horticultural waste.
To reduce the moisture content to the optimum level, it was decided to mix this with waste packing cases, conveniently available from the nearby freight terminal. Steam from the boiler now feeds a turbine that delivers electricity to the site’s energy centre – with any surplus fed into the grid. The hightemperature water downstream of the turbine drives absorption chillers, which generate chilled water.
pg 27 – exhaust gases from the biomass furnaces needed to be released from a very high level, necessitating the use of chimneys. In response, the team devised the plant-covered Supertrees around the chimney flues
pg 27 – the supertrees 18 of them between 25m and 50m high and
grouped in three clusters. have photovoltaiccells that capture solar energy which can be used for functions such as lighting and the collection of rainwater, used for irrigation and fountain displays. They also serve as air intake and exhaust functions, part of the
conservatories’ cooling systems with an elevated walkway between two of the larger Supertrees
pg 27 – Each tree is supported by cylindrical precast concrete rings, forming a hollow core, cantilevering from the ground
and supporting all the environmental devices. The skin is an interconnected array of steel members giving the appearance of
branches growing from the ground, fanning out to a broad canopy at the top. The strength is in the shape of the surface.
pg 28 – Treating humid air is notoriously energy-intensive: in a conventional system, the air supply would beovercooled by using chilled
water to remove the water vapour by condensation, and then reheated to achieve the required temperature. Instead, the design team looked to a technology used in the southern United States to cool industrial buildings such as food stores: desiccant conditioning systems / (NQ – how did grimshaw come up with technology through nature)
pg 28 – Desiccants are commonly found in packaging to keep equipment such as cameras dry before sale. They work by directly removingm moisture from air through a chemical process, usually by using the water-absorbent qualities of materials that are composed of salts.
pg 28 – These materials can also be liquids: in effect, very strong solutions of salty water that are so salty they absorb water from
air that passes through a spray of these solutions. Removing water from the air in this way results in the air heating up (the reverse
of evaporative cooling).
pg 28 – When combined with conventional cooling, liquid desiccant technology can deliver air at the required temperature and humidity with less energy than a conventional system.