Energy Monitoring and Targetting

8.1 Definition

Energy monitoring and targeting is primarily a management technique that uses energy information as a basis to eliminate waste, reduce and control current level of energy use and improve the existing operating procedures. It builds on the principle“you can’t manage what you don’t measure”. It essentially combines the principles of energy use and statistics.

While, monitoring is essentially aimed at establishing the existing pattern of energy consumption, targeting is the identification of energy consumption level which is desirable as a management goal to work towards energy conservation.

Monitoring and Targeting is a management technique in which all plant and building utilities such as fuel, steam, refrigeration, compressed air, water, effluent, and electricity are managed as controllable resources in the same way that raw materials, finished product inventory, building occupancy, personnel and capital are managed. It involves a systematic, disciplined division of the facility into Energy Cost Centers. The utilities used in each centre are closely monitored, and the energy used is compared with production volume or any other suitable measure of operation. Once this information is available on a regular basis, targets can be set, variances can be spotted and interpreted, and remedial actions can be taken and implemented.

The Monitoring and Targeting programs have been so effective that they show typical reductions in annual energy costs in various industrial sectors between 5 and 20%.

8.2 Elements of Monitoring & Targeting System

The essential elements of M&T system are:

• Recording -Measuring and recording energy consumption
• Analyzing -Correlating energy consumption to a measured output, such as production quantity
• Comparing -Comparing energy consumption to an appropriate standard or benchmark
• Setting Targets -Setting targets to reduce or control energy consumption
• Monitoring -Comparing energy consumption to the set target on a regular basis
• Reporting -Reporting the results including any variances from the targets which have been set
• Controlling -Implementing management measures to correct any variances, which may have occurred.

Particularly M&T system will involve the following:

• Checking the accuracy of energy invoices
• energy costs to specific departments (Energy Accounting Centres)
• Determining energy performance/efficiency
• Recording energy use, so that projects intended to improve energy efficiency can be checked
• Highlighting performance problems in equipment or systems

8.3 A Rationale for Monitoring, Targeting and Reporting

The energy used by any business varies with production processes, volumes and input. Determining the relationship of energy use to key performance indicators will allow you to determine:

• Whether your current energy is better or worse than before
• Trends in energy consumption that reflects seasonal, weekly, and other operational parameters
• How much your future energy use is likely to vary if you change aspects of your business
• Specific areas of wasted energy
• Comparison with other business with similar characteristics - This “benchmarking” process will provide valuable indications of effectiveness of your operations as well as energy use
• How much your business has reacted to changes in the past
• How to develop performance targets for an energy management program

Information related to energy use may be obtained from following sources:

• Plant level information can be derived from financial accounting systems—utilities cost centre
• Plant department level information can be found in comparative energy consumption data for a group of similar facilities, service entrance meter readings etc.
• System level (for example, boiler plant) performance data can be determined from sub-metering data
• Equipment level information can be obtained from nameplate data, run-time and schedule information, sub-metered data on specific energy consuming equipment.

The important point to be made here is that all of these data are useful and can be processed to yield information about facility performance. The Figure 8.1 shows the various steps involved in a comprehensive energy monitoring and targeting system.