Introduction
Machine and process design: the untapped innovation space for energy efficiency
Theoretical basis
Design aspects
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Geometries of machine components | Heat losses and recovery |
Suitability of machine components related to functions (particularly type of motors) | Process agents |
Surface energy and lubrication of machine components | Process sequencing |
Materials densities of moving machine components | Throughput |
Efficiency of machine-embedded power and heat conversions | Ingredient and product properties |
Quality aspects (definitive reference: IEEE Standard 1159-2009) | |
Power supply (including power factor) | Installation |
Equipment (particularly motors) | Operation |
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Increasing precision in time and space
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Increasing flexibility, particularly of the ‘Tool’ component of the system
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Increasing self-actuation and control
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Decreasing tangibility.
Principle | Technology/product | Originator/owner |
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2: Taking out | Variable capacity fermentation tank—match tank volume to product volume | Core Equipment Ltd |
35: Parameter step change | Solid-state caloric materials | Beko plc/U of Cambridge |
4: Asymmetry | Fibonacci-based impeller design (biomimetic spirals) | Pax Scientific |
6: Universality | Jet fluid flows for simultaneous mixing, pumping and cooking | OAL Ltd |
Measured effects of design innovations
References | Technology | Energy reduction |
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Chhanwal et al. (2014) | Hybrid oven − convection (electrical) + infrared | In a lab-scale oven, showed a 28% reduction in energy consumption to bake a large loaf and a 28% reduction in baking time, compared to convection alone. Product quality was the same. |
Fuchs Lubricants (Fuchs Lubricants Website, 2018 and personal communication, July 2018) | Synthetic food-grade lubricants | Self-reported 1.5–2% reduction in friction against competitor synthetic food-grade lubricants. |
Cambridge Engineered Solutions (Cambridge Engineered Solutions 2018) | Lightweighting of moving parts—proprietary ‘PacLite’ flatwire conveyor (for larger items such as potatoes) | “PacLite is 30–50% stronger than a standard flatwire belt and weighs 10% less than its predecessor, PacTitan®.” Energy savings not reported, but should be in line with the weight reduction. |
TOMRA (TOMRA Website 2018) | Eco Steam Peeler | Reduces energy consumption by 20–25% compared to the previous state of the art. Details sketchy in descriptive sources (there are no relevant patents with Tomra as assignee), but the main innovations seem to be to do with changing from fixed steam supply to controlled steam management, pressure vessel design and shape, including reducing the void volume, and improving heat transfer to the surface of the product through the design of the product mixing process. |
Yaskawa Technical features and specification at Yaskawa Website (2018) | U1000 Industrial Matrix Drive | No quantified energy savings claims made, but the technical features provide solid support for improved efficiency compared to 12- and 18-pulse drives: Avoids conversion of AC input to DC pulses to provides ultra-low harmonics, and regeneration through two-way current flow Reduces input harmonics by combining active switching from the power source along with integrated input filtering Very low current distortion of 3% to 5% at all speeds and loads. (Conventional AC drives range from ~ 15 to ~ 90%, depending on design and load.) Energy recovery, returned directly back to the power supply, avoiding the cost of regenerative rectifiers |
Oh et al. (2016) | Switching from pure to mixed refrigerants without capital works | “… savings of shaft power required for the refrigeration cycle can be achieved from 16.3% to 27.2% when the pure refrigerant is replaced with mixed refrigerants and operating conditions are re-optimised.” |
Pax Scientific (Harman 2013) | Biomimetic design of impellers for fans, pumps and mixers | Fan energy reduction of up to 50% (depending on application; based on measured but undisclosed data). Up to 90% less energy used to destratify water through mixing (based on data from over 600 large municipal drinking water storage tanks) |
Medeiros da Silva (2015) | Changes in machine code controlling trajectory motion profiles of motors | 5–10% reduction in energy consumption in single- and multi-axis machine co-ordination systems |
Testing Hypothesis 1: making machine energy data comparable
Product definition
Function definition
Product creation—chemical/biochemical |
React ingredients within and between themselves and/or with production agents |
Prevent reactions |
Product creation—physical |
Mix or associate ingredients (in any phase or form) and production agents |
Break down, separate/extract and form |
Product—external interfaces |
Wrap, enclose |
Move—deliver and input ingredients and production agents, package product and move packaged goods |
Remove and neutralise negative elements in the processing environment (cleaning) |
Sensing and control |
Profile product and process state |
Control or change product and process state |
Other variables
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Manufacture of the product is best done in the climate requiring the least energy input, so should be relocated.
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The manufacturer should improve insulation of the building and/or machinery, a one-off capital cost which will fall out of operational costs after a period.
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The climate disadvantage could be removed by investment in interseasonal solar heat storage systems (an innovation which might not otherwise have been identified).
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The effect of climate should be removed from the data (by, for example, relating it to degree days) to normalise comparison of the product’s manufacture around the world (EN 16231:2012, the European standard on energy efficiency benchmarking, advises that these external factors should be accounted for (British Standards Institution 2012)).
Using comparable machine energy data to stimulate machine and process design innovation
Possible models
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Promoting the opportunity to food manufacturers through various channels
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Marketing energy monitoring and improvement services based on the machine energy data, some of which may be subsidised
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Providing those services on a one-to-one basis.
Proposed system
Testing Hypotheses 2 and 3: data visibility and peer benchmarking
Peer benchmarking: evidence of effectiveness
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alone reduced consumption, by about 6% compared to consumption before the experiment
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had its largest impact on the day it was received, and then decreased over time
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did not work when received by email, even with customers experienced in receiving their bills online
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completely eliminated the 8% gain in efficiency caused by a large financial reward (£100 for a 30% reduction in energy use over 2 months) when the two were presented together. This can be interpreted as a powerful effect of benchmarking information, because it overpowered the influence of a motivator which was stronger when presented alone.
Regulation (EU) 2017/1369: framework for energy labelling
US DoE MotorMaster + 3.0
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Data can be contributed anonymously and made available to others, with or without charge.
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DNV GL, data owners and third parties can develop apps to analyse, with or without charge, datasets on the platform.
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Peer benchmarking for two energy apps. One of these is ‘Eco Insight’, in which the use of various resources on ships is continuously monitored. ‘Vessel comparisons, fleet benchmarking and market benchmarking are inbuilt’ giving sight of ‘where you stand and what your improvement potential is.’ This is analogous to exposing energy-related differences in machine design.
The challenges of data sharing
Participation
Data security
Identity
Experimental variables
Dependent variable: | Energy consumption differences (league tables) by machine brand for a defined intermediate or final food product. |
Independent variables: | Food manufacturer behaviour following sight of comparative data (Hypothesis 2) |
Food manufacturer behaviour following sight of analysis of the data and the potential for machine and process innovation (Hypothesis 3). | |
Control variable: | Food manufacturer behaviour following sight of their own data. |
Baseline variable: | Food manufacturer behaviour prior to sight of any data from this experiment (‘pre-treatment’). |
Testing Hypothesis 3: data quality requirements
Diagnostic and innovation analysis
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Current and voltage separately over time
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Power over time, which can be useful separately to energy consumption values
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Specific energy consumption (SEC, see ‘Other variables’ above)
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Power factor
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Harmonic distortion
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Thermal flux in relation to product and equipment materials and process fluids
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Specific enthalpy, entropy, Gibbs Energy, Helmholtz Energy and exergy.
Data acquisition protocols
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Environmental Technologies Verification (ETV) scheme (Europe)
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International Performance Measurement and Verification Protocol (IPMVP) (USA)
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EN 16231:2012Energy efficiency benchmarking methodology
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BS ISO 20140 seriesAutomation systems and integration—evaluating energy efficiency and other factors of manufacturing systems that influence the environment
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ISO 50006Environmental Management Systems: measuring energy performance