Even during periods of economic turmoil, the environment remains a key issue for our world.
By 2050, it is estimated that there will be two billion more people living in the world’s cities which, according to experts, will mean that world construction will grow by more than 70% and reach $15 trillion by 2025, outpacing global GDP. Part of the solution is to build with steel – 50% of steel is used in construction. With four people per house, this will mean providing 1,427 homes every hour, with most of them needed in Asia and Africa. How can such growth be made sustainable?
As most people are aware, steel is used in so many important applications, from bridges and other large constructions, trains and rail lines to industrial machinery, housing, offices, hospitals, cars, buses and bicycles, to name but a few examples. Steel delivers a number of unique environmental benefits, such as product longevity, recyclability, easy transportation and less raw material wastage. In addition, steel offers architectural and design flexibility due to its inherent strength, which allows large span distances and curves to be easily incorporated into designs.
Perhaps best of all, steel is 100% recyclable, without losing any of its properties or strength, and thus reducing the solid waste stream, which results in saved landfill space and the conservation of natural resources. Indeed, more steel is recycled each day than any other material. Even better, the steel industry as a whole has dramatically improved its energy efficiency over the past 30 years, cutting energy consumption by 50% per tonne of steel produced and substantially reducing carbon dioxide (CO2) emissions, also per tonne of steel.
The industry is always looking for ways to improve, and to that end a project is in place in the United States that explores the possibility of replacing carbon with hydrogen in blast furnaces. In addition, ULCOS, which stands for Ultra–Low Carbon Dioxide(CO2) Steelmaking, is a consortium of 48 European companies and organisations from 15 European countries that have launched a co-operative research and development initiative to enable drastic reduction in CO2 emissions from steel production. The consortium consists of all major EU steel companies, energy and engineering partners, research institutes and universities and is supported by the European Commission. The aim of the ULCOS programme is to reduce today’s CO2 emissions by at least 50%.
From a human health perspective, steel frames have proven ideal for the ‘healthy home’ concept. The incidence of asthma and sensitivity to chemicals is on the increase and steel frames have been used to achieve allergen-free and dust-free interiors. This requires techniques such as special sealing around windows, moisture barrier systems in the walls, extensive insulation, and whole house ventilation systems. Steel frames retain their original dimensions, which is a major factor in maintaining effective long-term sealing.
Steel is already being used to help manufacture lighter, more fuel-efficient vehicles as well as renewable energy infrastructure including wind turbines, solar installations, smart electric grids and energy-efficient housing and commercial buildings. Its economic benefits include its quick construction off-site, which means less site disturbance and waste, more usable floor space, e.g. thinner floors allowing for more stories in a building, the flexibility to re-configure buildings and steel has a long life with low maintenance, plus energy efficiency for lower operating costs.
Ashley G. // Editor SMC