The Square Kilometre Array: is it the wrong big science for New Zealand?

I've previously written about the problems besetting some mega-budget science projects and the notion that perhaps they should lose precedence to smaller programmes with quicker returns to both science and society. Of course there are advantages to long-term international STEM collaboration, including social, economic and political benefits, but there is a good case for claiming that projects are sometimes initiated without a full appreciation of the details.

Take for example, the Square Kilometre Array or SKA, the largest science project New Zealand has ever been involved with. Headquartered at the UK's Jodrell Bank Observatory (incidentally, I've been there a few times and it's well worth a visit if you're in the vicinity), twelve key nations are collaborating to construct two main arrays, one in Australia and the other in South Africa and some of its neighbours. The combined arrays will have a sensitivity fifty times greater than previous radio telescopes, allowing them to survey the sky far faster than has been done before and look back in time much earlier than current instruments.

But such paradigm-shifting specifications come with a very high price tag – and the funding sources are yet to be finalised. The €1.8 billion project is scheduled to start Phase 1 construction in 2024 and aims to begin observations four years later. Research will include a wide range of fundamental astrophysical questions, from exploring the very early universe only 300,000 years after the Big Bang to testing general relativity, gaining information on dark energy and even some SETI research.

The New Zealand contribution is organised via the Australia-New Zealand SKA Coordination Committee (ANZSCC) and is geared towards data processing and storage. The Central Signal Processor and Science Data Processor are fundamental components of the project, since the radio telescopes are expected to generate more data than the world currently stores.  As well as closer collaboration between the scientists and engineers of various nations, one of the aims of SKA is to become a source of public science education, something I have repeatedly pointed out is in desperate need of improvement.

So if this all seems so promising, why has the New Zealand Government announced that it may pull back from committing the outstanding NZ$23 million (equal to less than 10% of Australia's funding)? To date, the country has paid less than NZ$3 million. In 2015 I discussed the danger of the country falling behind in cutting-edge STEM research and Rocket Lab aside (which is after all, an American-owned company despite its kiwi founder) the situation hasn't really changed. so why did Research, Science and Innovation Minister Megan Woods declare this potential about turn, which may well relegate New Zealand to associate membership status?

The initial answer appears to be one of pure economics. Although the project is generating development of world-class computer technology, a report has questioned the long-term benefits from investing such comparatively large sums of public money. India is already an associate member while Germany has been considering a similar downgrade for some years and Canada may follow suit. The project is already  a decade behind schedule and New Zealand had hoped to be an array-hosting nation but lost out due to a lower bid from South Africa. SKA is run by a same-name not-for-profit organisation and so presumably any financial rewards are of a secondary nature (perhaps along the lines of patents or new technologies that can be repurposed elsewhere).

Interestingly, New Zealand's science community has been divided on the issue. While Auckland University of Technology and Victoria University of Wellington have objected to the downgrade, the university of Auckland's head of physics Richard Easther has support the Ministry of Business, Innovation and Employment (MBIE) decision, saying that far from providing financial and long-term science benefits (in both applied computing and astrophysical data), SKA is a white elephant, hinting that it might well be obsolete by the time it starts gathering data.

Another University of Auckland astrophysicist, Dr Nick Rattenbury, argues that the nation's public funding infrastructure is currently too primitive for it to become involved in such international mega-budget STEM projects. I simply don't know enough detail to question whether such adages as you need to speculate in order to accumulate apply here; it's clearly a well-thought out programme, unlike say the politically-motivated yet vague and probably unworkable Predator Free 2050 scheme.

If SKA was committed to solving an immediate practical problem in the fields of say, environmental degradation, food and water production, or medicine, I would probably have no hesitation in supporting it whole-heartedly, regardless of the cost to the public purse. But the universe has been around almost fourteen billion years, so I for one don't mind if it holds onto a few of its fundamental secrets for a little while longer.

Concrete: a material of construction & destruction - and how to fix it

How often is it that we fail to consider what is under our noses? One of the most ubiquitous of man-made artifices - at least to the 55% of us who live in urban environments - is concrete. Our high-rise cities and power stations, farmyard siloes and hydroelectric dams wouldn't exist without it. As it is, global concrete consumption has quadrupled over the past quarter century, making it second only to water in terms of humanity's most-consumed substance. Unfortunately, it is also one of most environmentally-unfriendly materials on the planet.

Apart from what you might consider to be the aesthetic crimes of the bland, cookie-cutter approach to International Modernist architecture, there is a far greater issue due to the environmental degradation caused by the concrete manufacturing process. Cement is a key component of the material, but generates around 8% of all carbon dioxide emissions worldwide. As such, there needs to be a 20% reduction over the next ten years in order to fulfil the Paris Agreement - yet there is thought there may be a 25% increase in demand for concrete during this time span, particularly from the developing world. Although lower-carbon cements are being developed, concrete production causes other environmental issues as well. In particular, sand and gravel extraction is bad for the local ecology, including catastrophic damage to the sea bed.

So are there any alternatives? Since the 1990's, television series such as Grand Designs have presented British, New Zealand and Australian-based projects for (at times) extremely sustainable houses made from materials such as shipping containers, driftwood, straw bales, even shredded newspaper. However, these are mostly the unique dream builds of entrepreneurs, visionaries and let's face it, latter-day hippies. The techniques used might be suitable for domestic architecture, but they are impractical at a larger scale.

The US firm bioMASON studied coral in order to develop an alternative to conventional bricks, which generate large amounts of greenhouse gases during the firing process. They use a biomineralisation process, which basically consists of injecting microbes into nutrient-rich water containing sand and watching the rod-shaped bacteria grow into bricks over three to five days.  It's still comparatively early days for the technology, so meanwhile, what about applying the three environmental ‘Rs' of Reduce, Reuse and Recycle to conventional concrete design and manufacturing?

1 Reduce

3D printers are starting to be used in the construction industry to fabricate building and structural components, even small footbridges. Concrete extrusion designs require less material than is required by conventional timber moulds - not to mention removing the need for the timber itself. One common technique is to build up shapes such as walls from thin, stacked, layers. The technology is time-effective too: walls can be built up at a rate of several metres per hour, which may induce companies to make the initial outlay for the printing machinery.

As an example of the low cost, a 35 square metre demonstration house was built in Austin, Texas, last year at a cost of US$10,000 - and it only took 2 days to build. This year may see an entire housing project built in the Netherlands using 3D-printed concrete. Another technique has been pioneered at Exeter University in the UK, using graphene as an additive to reduce the amount of concrete required. This greatly increases both the water resistance and strength compared to the conventional material, thus halving the material requirement.

2 Reuse

Less than a third of the material from conventionally-built brick and timber structures can be reused after demolition. The post-war construction industry has continually reduced the quality of the building material it uses, especially in the residential sector; think of pre-fabricated roof trusses, made of new growth, comparatively unseasoned timber and held together by perforated connector plates. The intended lifespan of such structures could be as little as sixty years, with some integrated components such as roofing failing much sooner.

Compare this to Roman structures such as aqueducts and the Pantheon (the latter still being the world's largest unreinforced concrete dome) which are sound after two millennia, thanks to their volcanic ash-rich material and sophisticated engineering. Surely it makes sense to use concrete to construct long-lasting structures, rather than buildings that will not last as long as their architects? If the reuse of contemporary construction materials is minimal (about as far removed as you can get from the traditional approach of robbing out stone-based structures in their entirety) then longevity is the most logical alternative.

3 Recycle

It is becoming possible to both recycle other waste into concrete-based building materials and use concrete itself as a secure storage for greenhouse gases. A Canadian company called CarbonCure has developed a technique for permanently sequestering carbon dioxide in their concrete by converting it into a mineral during the manufacturing process, with the added benefits of increasing the strength of the material while reducing the amount of cement required.

As for recycling waste material as an ingredient, companies around the world have been developing light-weight concrete incorporating mixed plastic waste, the latter comprising anywhere from 10% to 60% of the volume, particularly with the addition of high density polyethylene.

For example New Zealand company Enviroplaz can use unsorted, unwashed plastic packaging to produce Plazrok, a polymer aggregate for creating a concrete which is up to 40% lighter than standard material. In addition, the same company has an alternative to metal and fibreglass panels in the form of Plaztuff, a fully recyclable, non-corroding material which is one-seventh the weight of steel. It has even been used to build boats as well as land-based items such as skips and playground furniture.

Therefore what might appear to be an intractable problem appears to have a variety of overlapping solutions that allow sustainable development in the building and civil engineering sector. It is somewhat unfortunate then that the conservative nature of these industries has until recently stalled progress in replacing a massive pollutant with much more environmentally sound alternatives. Clearly, green architecture doesn't have to be the sole prerogative of the driftwood dreamers; young entrepreneurs around the world are seizing the opportunity to create alternatives to the destructive effects of construction.