HSE


savvy move, given his employer lately raised €11m in new investment. As Dölerud emphasises, moreover, there are plenty of ways to understand this surge in popularity. One, he says, is that “engineered wood material production” has now reached cost-effective levels. Another, Dölerud continues, involves better technology. Where it historically required serious computers to untangle the precise cost-benefits of wooden blades, that work can now be done on a regular laptop. All this excitement is doubtless reflected in Modvion’s own work. Quite aside from that welcome injection of cash, Renewable Energy Systems (RES), a major British renewable energy company, recently announced plans to use Modvion’s expertise to build around 200 wooden turbines through 2036, a deal that could represent over $353m. Nor is focus limited to towers. In Germany – as the name suggests – Voodin Blades is developing wooden blades, starting a journey that could one day banish unsustainable fibreglass to the scrapheap.


Above: Wooden towers can potentially enjoy a 300-year afterlife, as a more renewable material than steel.


Opening page: According to Modvion, each 150m wooden tower can capture 2,000t of CO2


. 200


The number of wooden turbines that Modvion will be building for RES through to 2036. Modvion


38


presumably realised, Kamkwamba’s story was partly so engaging because of its current unusualness. For if he used wood for his proto-turbine, modern commercial ones are normally made from steel: a lot of steel. According to estimates by ArcelorMittal, a Luxembourg steel manufacturer, up to 180t of the stuff are needed for every megawatt of offshore wind power. That makes sense: with the tallest towers under development now soaring some 274m into the sky, foundries are battling to fulfil demand. Not that wood-based wind energy is by any means dead. Given the whole industry is predicated on environmentalism, in fact, it’s arguably surprising just how long it’s taken to make a comeback – even as it now promises to transform the sector at speed.


Wind in the willows


Erik Dölerud is in an excellent position to appreciate the role of wood in the modern wind industry. A Swedish native, he’s spent over a decade immersed in the field, working on everything from hydrodynamic analysis to motion simulation. Moving to timber-centric turbine manufacturer Modvion in 2017, he now works as the company’s senior development engineer – a


That last point is worth spending a moment on. For if better technology and investment are surely prodding wooden turbines into the spotlight, the limitations of existing materials are equally important. And if that’s increasingly obvious when it comes to blades – burning fibreglass emits toxic air pollutants like styrene – it’s arguably true of steel towers as well. Perhaps the most pressing concern here, suggests Professor John Hall of the State University of New York at Buffalo, is the steel supply chain. Still battling a pandemic-prompted price surge, with costs jumping by 100% in the 12 months following August 2020, wood increasingly feels like a plausible alternative. Timber arguably beats steel in the sustainability stakes too. While the latter can definitely be recycled, Hall says that timber is a more innately “renewable” material, pointing out that thoughtful harvesting strategies are becoming ever more prevalent. Dölerud agrees, noting that old wooden towers can potentially enjoy a 300-year afterlife everywhere from housing beams to paper. These benefits are echoed by the wider statistics too. As Modvion has found, each 150m wooden tower captures 2,000t of CO2


. Compare that with


steel, which together with concrete contributes a stonking 15% of global carbon emissions, and it’s easy to see why a sustainability-obsessed industry should be so excited by timber.


Timbering up


Beyond these broader economic and environmental factors, meanwhile, there are strong technical reasons to embrace the wooden revolution. A famously tough building material, steel can’t easily be shaped, instead requiring manufacturers to


World Wind Technology / www.worldwind-technology.com


Modvion


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45