What is an Energy Audit?
An energy audit is an inspection survey and analysis of energy flow for energy conservation in a facility. The primary objective is identification of energy saving opportunities, a qualitative analysis of the implementation of energy saving measures and an estimation of its potential energy saving.
In commercial and industrial set up, an energy audit is the first step in identifying opportunities to reduce energy expense and carbon footprint.
Energy Audit can broadly be classified into home/Residential energy audit and Industrial Energy Audit.
Home Energy Audit.
This involves evaluating the energy efficiency of a house/building energy with the aim to suggest the best ways to improve energy efficiency. This has a keen access to the efficiency, physical condition and settling of the heating, ventilation, air conditioning equipment which are the major energy consumers for buildings.
The approach for this audit is an energy use review for a given time period, say a year, and the homeowner’s billing history is available showing the quantities of electricity, LPG, fuel oil, or other energy sources consumed over a one or two-year period.
Home energy audit will also include inspection and recording of the various characteristics of the building envelope including the walls, ceilings, floors, doors, windows, and skylights with the motive to quantify the building’s overall thermal performance
The end goal of this exercise is to identify cost effective ways to improve the comfort and efficiency of buildings. In addition, this is very crucial in determining the energy requirement thus designing and realizing a solar photovoltaic (PV) or Solar water heating installation. This is because it allows finding out the necessary peak power as well as the required size of the battery, the charge controller and the inverter.
Industrial Energy Audit.
A clamour of reduced operational costs in the manufacturing, especially in the midst of a global pandemic, has resulted in an exploded demand for industrial energy audits. This is an attempt to lower increasingly expensive energy costs and move towards a sustainable future.
Legislation around Industrial Energy Audit will vary from one country to another.
In Kenya, for instance, this is guided by the Energy Management Regulations 2012, which makes it mandatory for an establishment/business that consumes more than 180,000kWh/ 648,000Mj per year (Designation of Energy Users Gazettement) is required to conduct an energy audit tri-annually.
Energy auditors during a walk-through in a facility.
Industrial Energy audit will entail:-
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The analysis of utility data, including study of the installed equipment and analysis of energy bills;
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The survey of the real operating conditions and operational procedures;
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The understanding of the building behaviour and of the interactions with weather, occupancy and operating schedules;
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In depth interviews and consultation with facility personnel to properly understand energy usage;
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The selection and the evaluation of energy conservation measures and estimation of energy saving potential.
There are three main types of Industrial energy Audits:-
1. Walk-through energy audit
2. Detailed/General energy audit
3. Investment-Grade energy audit
Walk-through Audit
This is the simplest and quickest type of audit. It involves interviews with site-operating personnel, a brief review of facility utility bills and other operating data.
This will also entail a walk-through of the facility to become familiar with the facilities operation and to identify any glaring areas of energy waste or inefficiency.
Corrective measures are briefly described, and quick estimates of implementation cost, potential operating cost savings, and simple payback periods are provided.
However, the level of detail captured in this audit may not be very sufficient for reaching a final decision on implementing proposed measures and this may require a further more detailed audit.
This will be more detailed than a walkthrough Energy audit, whereby more detailed information about the operation of a facility is collected and analysed and the more detailed evaluation of energy conservation measures is done
Utility bills for about a 12- to 36-month period will be collected and analysed for energy usage trends and signs of energy wastage.
In addition this will entail:
✔ Additional metering and power logging of significant energy-consuming systems is often performed to supplement utility data.
✔ A More detailed interviews with facility operating personnel are conducted to provide a better understanding of major energy consuming systems and to gain insight into short- and longer-term energy consumption patterns.
✔ A detailed financial analysis for each measure based on detailed implementation cost estimates and site-specific operating cost savings. This will include a justification for implementation of proposed energy conservation projects.
Investment Grade Energy Audit
The investment-grade audit expands on the general energy audit.
It will entail detailed evaluation of technical and economic issues necessary to justify the investment related to energy conservation with a stress on expected return on Investment. (ROI)
Conclusion
An energy audit is very essential in determining energy consumption associated with a facility or even a building at home, it will help you see the potential savings associated with that energy consumption and helps reduce environmental damage and pollution!
The world today is facing a serious energy challenge with demand for electricity growing every day, thus, pressure to reduce energy consumption and lower greenhouse gases (GHG) emissions.
An energy audit for your home or Industrial facility is the first starting point towards saving energy costs and playing an active role in building a more suitable world