Energy-Mass Balance

In this topic we will explore an energy and material flow perspective. Energy and mass takes many forms, and could apply to any energy input and output into your system. Our key driver in analysing energy is to improve energy efficiency by looking for opportunities to make our system more effective. This often has many co-benefits, including cost savings and improving environmental outcomes.

Example applications

An energy-mass balance is a practical application of the First Law of Thermodynamics and Conservation of Mass principles. Two case studies are provided in the core resources, conducting an EMB of a commercial building and of a transport system. In an EMB, the flows in must be accounted for in the flows out, or must accumulate in the system, such as material stored in inventory or heat energy stored in a building. The goal of conducting an EMB is to then identify opportunities for reducing costs through minimising flows or waste.

Steps

There are five iterative steps of constructing an EMB: develop a plan, collect data, map the system, analyse the EMB, and consider improvements for the next version. For the purposes of the course, we will only explore the collect data and map the system steps. This involves:

• identifying mass or energy inputs and outputs

• collecting metering data, using a simulation or modelling software, or estimate using engineering calculations (for our purposes, these can be rough estimates)

• mapping the flows into an energy-mass balance map

Key concepts

• an explanation of a the key aspects of an energy-mass balance audit
• an example that conceptually walks through the process of constructing an EMB map
• advice to the student engineer on how to improve the system after the EMB map is constructed

Core resources

There are two particular examples of Energy Mass-Balance audits relevant to your projects:

• Commercial Buildings (heaps of great examples){: .link-ext target=”_blank” }

• Transport (a good example of an EMB process, but doesn’t include an EMB map){: .link-ext target=”_blank” }.

• (All Energy Efficiency Opportunities resources)

Similar tools…

Once you have built an EMB map, explore the opportunities to improve the energy or material efficiency of the system.