ENGT5220: Industrial Energy Systems for Low Impact Manufacturing

This report provides a consultant's perspective on industrial energy systems within the context of bread manufacturing. It begins by identifying the three most significant energy-using processes: mixing, baking, and cooling. The report then utilizes a Sankey diagram to illustrate energy flows, conversions, and losses within a bakery, highlighting the conversion of chemical energy to thermal energy and identifying waste heat as a major loss. The report further explores the application of renewable energy technologies, such as solar and biomass, to optimize energy consumption in mixing, baking, and cooling processes. The conclusion emphasizes the importance of adopting these technologies to minimize energy losses and promote sustainable practices in the food industry. The report is based on the 'Low Impact Manufacturing' course, with the aim of assessing energy efficiency in the food sector. The report covers topics such as energy-intensive processes, the Sankey diagram, and renewable energy technologies.

Running Head: INDUSTRIAL ENERGY SYSTEMS 0
Industrial Energy Systems
Low Impact Manufacturing
(Student Details: )
3/1/2020

INDUSTRIAL ENERGY SYSTEMS 1
Contents
Low Impact Manufacturing: Bread............................................................................................2
Introduction................................................................................................................................2
Identification of three most significant energy using processes................................................2
Mixing process.......................................................................................................................2
Baking process.......................................................................................................................3
Cooling process......................................................................................................................3
Sankey diagram with flows, conversions and losses.................................................................3
Sankey diagram of bakery energy consumption and distribution..............................................3
Renewable energy technologies.................................................................................................4
Conclusion..................................................................................................................................4
References..................................................................................................................................6

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Low Impact Manufacturing: Bread
Introduction
The report is based on the ‘Low Impact Manufacturing’ course while focusing on a
consultant’s viewpoint for a manufacturing firm. In doing so, the paper is going to present a
consultant viewpoint specializing in energy efficiency in the food sector. From the chosen
sector, product Bread has been selected in order to audit a wide range of different
manufacturers in the sector. In general, all food products require industrial energy systems for
activities like cooling, heating, cooking, baking, mixing, refrigeration, pasteurization and
cleaning (University of Sheffield, 2017). Thus, energy use should be minimized and
optimized with renewable energy technologies. Therefore, by using the three most significant
energy utilising processes, the Sankey diagram with the losses, conversions, and flows, will
be discussed in the context of the Bread Manufacturing Process (BMP).
Source: (Frangoul, 2017)
Identification of three most significant energy-using processes
In this section, the discussion is going to identify the 3 most important energy utilising
processes which are involved in the chosen product manufacture process (DEFRA Gov.,
2012). Based on research, it has been found that there are three important energy-consuming
processes in the process of bread manufacturing as mentioned below:
Mixing process
This process of bread manufacturing is essential and hence plays a key role. The mixing
process is used to homogenisation of formula ingredients like flour, sugar, salt and many

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more (University of Sheffield, 2017). This process uses high energy as mixers include low
speed, twin-spiral, spiral, high speed and Chorleywood bread process compatible mixers
causes high energy consumption. the whole mixing process is significant from the energy
utilisation point of view. It is because the mixers used for mixing impart high-level of
mechanical energy to the bread dough in a very short period of time (Italian Foodtech, 2017).
Baking process
In general, when the bread is getting baked in the oven then the baking process requires a
high amount of energy (Svanes et al., 2019). In this context, the temperature needed for the
bread baking varies in the range of 220 degrees to 250-degree centigrade. In addition to that,
high thermal or heat energy is needed because at the time of baking, the dough center’s
temperature reaches 95-degree centigrade for ensuring the product structure is wholly set
(Frangoul, 2017). Moreover, the bread dough is placed in the oven and hence energy in the
form of heat is usually transferred to the dough. This energy transfer and use are usually
occurring into several mechanisms like convection, conduction, radiation, and condensation
of steam as well as evaporation of water. Thus, the usual baking time of bread is 25 to 30
minutes and hence energy used during baking is significant and considerable (Martinko,
2017).
Cooling process
It is worth knowing that BMP contains a phase of cooling where proper cooling of bread is
required before wrapping and final packaging. In the cooling process, there are condensers,
cooling water pumps and coolers are used to cool the temperature of the bread as needed
(DEFRA Gov., 2012).

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Sankey diagram with flows, conversions, and losses
Sankey diagram of bakery energy consumption and distribution
Source: (Zvenigorodsky et al., 2016)
The above is the Sankey diagram of bakery energy consumption and distribution. Here, the
above diagram is clearly illustrating the major energy flows into, within as well as out of the
facility, while showing the key energy conversion cycles in the bread manufacturing process
(Svanes et al., 2019). It is clear from the above figure that chemical energy is getting
converted into thermal energy. In the context of energy conversion during the whole
manufacturing, it is clear that the oven and boiler both are providing energy by consuming
fuel as chemical energy (Frangoul, 2017). There are different processes where energy
consumption, as well as energy losses, is being seen. From the Sankey Diagram of bakery
manufacturing, it is evident that maximum energy losses are occurring in the form of waste
heat. Such waste heat is the water vapour heat which is happening right above the useful
energy process for the baking of the bakery product (Italian Foodtech, 2017).
Renewable energy technologies
This section is dedicated to reviewing the suitability of renewable energy technologies for the
bread manufacturing process. In this context, renewable energy technologies must be used for
bakery manufacturing as it can save a lot of energy during the key processes like mixing,
baking, and cooling of the bread. A great example of renewable energy technologies is solar-
powered bakery manufacturing. Here, a solid biomass stove can further be used for further
bakery manufacturing. In addition to that, biogas is again a renewable energy source that can
be used for food processing and manufacturing in such cases (Zvenigorodsky et al., 2016).
Apart from this, solar energy-based cooker, oven, and dryer are helpful in conserving

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conventional energy resources for future use. On the other hand, solar refrigerators are the
best way to use renewable energy for the cooling process in bread manufacturing (University
of Sheffield, 2017). Likewise, biogas refrigerators can be highly useful for cooling purposes
in bakery manufacturing. In this way, with the help of the aforementioned renewable energy
technologies, the energy losses in the form of waste vapour heat can further be used for the
regeneration of the energy. Thus, by using renewable energy technologies such as biomass,
biogas, solar and many others, energy losses can be minimized (Sheffield, 2017).
Conclusion
In whole, the discussion has successfully explored low impact manufacturing of the chosen
food product like bread. With the help of bread manufacturing, this research paper has
narrated key points on industrial energy systems. While discussing various energy-consuming
processes into bread manufacturing, this paper has identified the key processes which use the
energy maximum. In addition to that, the Sankey Diagram of bakery manufacturing has been
drawn to demonstrate the main flows of energy within, into and out of the chosen facility. In
this way, by exploring main energy conversions that takes place into bread manufacturing,
this report has found renewable energy technologies like solar and biomass energy for further
energy conservation and optimization.

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References
DEFRA Gov., 2012. Green Food Project Bread Subgroup Report. UK: UK Government.
Frangoul, A., 2017. New research highlights environmental impact of… bread. [Online]
Available at: https://www.cnbc.com/2017/02/28/new-research-highlights-environmental-
impact-of-bread.html [Accessed 2020].
Italian Foodtech, 2017. Environmental impact and sustainability of the industrial production
of bread. [Online] Available at: https://www.italianfoodtech.com/environmental-impact-
sustainability-bread/ [Accessed 2020].
Martinko, K., 2017. What's the environmental impact of a loaf of bread? [Online] Available
at: https://www.treehugger.com/green-food/whats-environmental-impact-loaf-bread.html
[Accessed 2020].
Sheffield, 2017. How to reduce the environmental impact of a loaf of bread? [Online]
Available at: https://www.sheffield.ac.uk/news/nr/loaf-bread-energy-1.684676 [Accessed
2020].
Svanes, E., Oestergaard, S. & Hanssen, O., 2019. Effects of Packaging and Food Waste
Prevention by Consumers on the Environmental Impact of Production and Consumption of
Bread in Norway. Sustainability, 11(1), p.43.
University of Sheffield, 2017. How to reduce the environmental impact of a loaf of bread?
(Update). [Online] Available at: https://phys.org/news/2017-02-environmental-impact-loaf-
bread.html [Accessed 2020].
Zvenigorodsky, S., Chudnovsky, A. & Skop, H., 2016. Humidification of industrial process
flows by means of waste heat recovery. In First Thermal and Fluids Engineering Summer
Conference., 2016. First Thermal and Fluids Engineering Summer Conference.