Energy efficiency: Mechanical engineers seek to balance customer wishes and cost constraints

Marginal Column

For machine builders, energy-effective equipment and machinery represents a balancing act to find a compromise between customer wishes, costs, and the law.

 

25 percent less: This is the target that Volkswagen has adopted – to reduce both energy consumption and emissions. The car manufacturer from Wolfsburg has set its sights on becoming top of the class in economic and ecological terms by 2018. 20 percent less: This is the figure by which Procter & Gamble intends to reduce consumption and emission values per item produced by 2020. Beer brewing giant Heineken also has ambitious targets. This enterprise, active around the world, intends to emit 40 percent less CO2 in production by 2020.* These global players are three of a long list of companies who have embraced ambitious commitments with regard to energy consumption, climate protection, and resource management.

Target levels have been set and they are not just a marketing hype or to assuage a guilty conscience. Quite the opposite: The prime driving forces behind these major contributions toward environment and climate protection are hard-hitting commercial factors and legislation. Rising energy costs and increasingly active legislators are putting the pressure on companies and their technology contractors. Efficiency legislation – such as the Energy-related Products Directive issued by the EU or the compulsory reduction of energy intensity prescribed in the current five-year plan (2011 – 2015) being implemented by the Chinese government – is sending out a loud and clear signal: machinery and plant must be at the forefront when it comes to savings.

4EE – Systematic Efficiency

Individual measures such as retrofitting variable-speed pump drives from the Sytronix family can boost efficiency in short order. The most crucial factor, however, is the design of the machine itself. That’s because, when striving for the best possible efficiency level in a machine, everything depends on optimal coordination of operating sequences, the choice of components, selection of operating points for the axes, and intelligent energy management.

The mechatronics system simulation program offered by Bosch Rexroth provides new approaches on how to optimize savings throughout the machine. While previous simulations primarily aimed at improving performance and cycle times, Bosch Rexroth now expands this technology to achieve energy-efficient solutions. Engineers and designers are able to evaluate and optimize energy consumption by means of a virtual prototype.

This is a building block in the holistic approach that Bosch Rexroth has been practicing for several years in conjunction with Rexroth’s systematic program for energy efficiency (4EE).

 

Yes to efficiency, no to price premiums

Machinery manufacturers are feeling the pinch two-fold: firstly from their own internal cost constraints together with legislative requirements, and secondly from customers who pass on their energy efficiency requirements, letting their suppliers sort them out. European vendors are still a step ahead, but Asian machine manufacturers, and the Chinese in particular, are pressing forward with their efforts to improve efficiency. The Chinese government is now also promoting more efficient machinery and is following the example set by German incentive programs such as the national Reconstruction Loan Corporation (KfW). Public-sector entities in the USA are also redoubling their efforts to reduce industrial energy consumption.

Cost pressures remain high, with acquisition costs still being the decisive factor in many countries and sectors. When retrofitting businesses around the world with more energy-efficient components, amortization periods of up to three years are acceptable. When acquiring new equipment, however, the notion of total cost of ownership plays a role only for a minority of customers. A study published by Roland Berger** reflects this: “Many customers regard efficiency as an important factor when buying a machine. But as a rule they are not prepared to pay a premium for it.” Machine builders thus need to develop efficiency innovations that at the same time offer cost advantages to both themselves and their customers.


* Source: Voluntary commitments by the companies

** “Production Systems 2020”, January 2011