Perhaps the most critical trend was actually an absence: there was no-one showing high specification low-CO2 cement at the show. In previous years, at this show and at others, there would be a variety of companies showing off their low-energy, low CO2 cement - I’m thinking of companies like Cenin, Ecocem, Lafarge, Italcementi and HeidelbergCement - based on mineralisers or fluxes, on altering the ratios between the main clinker mineral phases, through the use of alternative raw materials (including blast furnace slags and ashes) or even the adoption of novel mineral systems such as MgO, rather than the more familiar CaO-CaCO3. This year there were no companies shouting about their cement products from the exhibition stands, but the importance of this is not yet clear. Have these novel approaches failed? Are the economics not yet right (particularly since the cost of CO2 emissions is still very low)? Or are these products quietly taking their place among the everyday, humdrum cement products that everyone now takes for granted? I think that it is likely to be a mix of all three.
One positive trend that I detected was that of home energy storage. This first hit the headlines when Elon Musk of Tesla (and SpaceX and eBay etc) announced in May 2015 that he had an invention1 that would change everything. What he announced was a lithium-ion battery that you could use to store energy at home (that announcement was rather ‘Apple-esque’ since this had been done before by other people, but he was proposing a slightly sexier way of doing it - like Apple announcing a smartwatch or a music player). Well, at Ecobuild, there were plenty of companies offering the same kind of devices, for solar and wind energy storage and even for storage energy taken from the grid when it is cheap and for use when it is expensive. This seems to me like a ‘no-brainer:’ the cost of the devices is coming down fast and even though they have a limited series of charge cycles (about 4000, enough for 20 years’ use), they will easily save their cost. Eventually, we will all have one.
The most novel departure from electrical home energy storage that I saw was a device that promises to store thermal energy - for example from a solar-thermal array. The heated water is ducted into a unit which contains a banks of cells of a particular salt - the heat being used to ‘melt’ the crystalline salt into a liquid. When the heat stored in the unit is required again, a small initiating electric charge is used to cause the salt to crystallise again, at which point it exothermically gives up its energy of crystallisation to the circulating cold water, heating it up. Apparently the system is very efficient, offering another means of gaining benefit from the free energy around us.
Another trend at the show was that of the number of stands originating from China, but staffed with forlorn, uninterested-looking personnel. The companies attending from China seem to have goods to offer to the market, and presumably they have cost advantages that are used to gain an edge in selling price over their competitors, but their staff almost all remained on their stands, engrossed in their devices, ignoring the visitors and perhaps missing home. Companies in China are very, very keen to sell their products, since the bottom has dropped out of their home markets: the Chinese economy is in a parlous state: debt levels are at around US$5.5tr (depending on how it is counted), and there are many ghost cities and zombie companies haunting the economy. If and when the loans that financed the ghost developments finally go bad, and when the companies are finally allowed to die, then we will have an economic hard landing in China that will rank alongside the US sub-prime disaster of 2007 - 2008 and which will make the current Chinese slowdown look like a walk in the park on a sunny spring day. No wonder they have sent their staff abroad to try and rustle-up some business. It’s just a pity that the staff would seemingly prefer to be anywhere else.
The final trend of note, perhaps not perfectly new but certainly a new twist - for me at least - was that shown by Professor Cruz of University College London, the director of BiotA Lab. His stand (right) showed the results of a 3-D printing project (‘Ho hum,’ I hear you say), but one that uses a variety of novel composite mixes, including cement, gypsum, marble, sand and cork. Add slag and ash into that list and you have the potential to make some real high-specification, low-energy, low-CO2 building materials. Watch this space - this is the future.
1 http://www.theguardian.com/technology/2015/may/01/tesla-announces-low-cost-solar-batteries-elon-musk