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Manufacturing


energy substitution (MES), process modification and control (PM) and new, cleaner technologies and processes (CT). These become the building blocks in either a supply or demand-side strategy for improving resource efficiency in manufacturing.


A supply-side strategy involves redesign and improving the efficiency of processes and technologies employed in the major materials-intensive subsectors of the manufacturing sector (ferrous metals, aluminum, cement, plastics, etc.). On the other hand, if a green economy means improving not only productivity but also efficiency by a factor of four or more, a demand-side strategy is also required.


A demand-side strategy involves changing the composition of demand, both from within industry and from final consumption. This requires modifying output, i.e. to use final goods embodying materials and energy much more efficiently and/or to design products that require less material in their manufacturing. For instance, the need for primary iron and steel from energy-intensive integrated steel plants can be reduced by using less steel downstream in the economy (i.e. in construction, automobile manufacturing, and so on). Design for dismantling is a key step in advancing re-use and recycling of, for example, metals contained in the end-product.


The supply-side and demand-side approaches consist mainly of the following components:


■ Re-design products and/or business models so that the same functionality can be delivered with fundamentally less use of materials and energy. This also requires extending the effective life-time of complex products and improving quality, by incorporating repair and remanufacturing into a closed-cycle system;


■ Substitute green inputs for brown inputs wherever possible. For example, introduce biomass as a source of chemical feedstocks. Emphasise process integration and upgrade of process auxiliaries such as lighting, boilers, electric motors, compressors and pumps. Practice good housekeeping and employ professional management;


■ Recycle internal process wastes, including waste- water, high temperature heat, back pressure, etc. Introduce CHP if there is a local market for surplus electric power. Use materials and energy with less environmental impact, e.g. renewables or waste as inputs for production processes. Advance recyclability of materials used and find or create markets for process wastes such as organics;


■ Introduce new, cleaner technologies and improve the efficiency of existing processes to leapfrog and


establish new modes of production that have a fundamentally higher material- and energy efficiency. To start with, major savings potential in manufacturing lies in improving the resource efficiency of existing processes; and


■ Redesign systems, especially the transportation system and urban infrastructure down-stream, to utilise less resource-intensive inputs. The first target must be to reduce the need for and use of automotive vehicles requiring liquid fuels in comparison to rail-based mass transportation, bus rapid transit and bicycles.


Note that these transitional changes will occur automatically only to the extent that they are perceived by


business managers and owners to increase


competitiveness. Moreover, the manufacturing sectors are intermediates, which means that what they produce depends both on the availability and cost of raw materials and on the demand from downstream sectors, final consumers and governments. The latter can influence business decision-making by introducing new standards or subsidies. To ensure that a strategic transition to sustainable industrial production is realised in different parts of the world, both public and private investment in leap-frogging technologies would be highly desirable.


Despite technological advances, there will always be some inefficiency and waste. What is possible, however, is to use resources much more efficiently than it is used now. There is plenty of room for doing so. The USA’s economy today converts primary energy into useful work – mechanical, chemical or electrical – with an aggregate efficiency of 13 per cent (Ayres and Warr 2009; Ayres and Ayres 2010). IEA data suggest that Russia, China and India remain less energy efficient than the USA (at least in the industrial sectors) (IEA 2009b). Japan, the UK and Austria are more efficient, overall, than the USA (20 per cent) (Warr et al. 2010). But this still means that more than 80 per cent, or four-fifths, of the high quality energy extracted from the earth is wasted. To cut that waste by only a quarter or a third could produce significant economic gains. From a macro-economic perspective, this is an enormous opportunity.


Closed-loop, circular systems in manufacturing Drawing on the principles of industrial ecology, closed- cycle manufacturing is a particularly ambitious approach to supply-side innovation. This concept refers to an ideal manufacturing system that maximises the useful life of products and minimises the waste and loss of valuable and scarce metals. At a broader systems level, another version of closed-cycle manufacturing is industrial symbiosis or eco-industrial parks. They are modeled on the Kalundborg (Denmark) example, within which wastes from certain manufacturing operations can be used as raw materials for others. In Kalundborg an oil refinery that produces


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