PART ONE
PULLOUT
HVAC & R
MODULE
94
Skills Workshop
PROUDLY SPONSORED BY
DEVELOPING A GAS MEASUREMENT AND MONITORING PLAN
PART ONE
PULLOUT
Gas is an important energy source and significant cost for many organisations throughout Australia. The diversity of uses and equipment involved can make gas consumption difficult and expensive to measure and monitor. However, by having a clear set of goals and understanding gas use, you can develop a targeted and cost-effective plan to manage it.
In this two-part series, Skills Workshop will guide you through the methodologies to prepare and implement a gas measurement and monitoring plan.
Step 1 Specify a goal and map what you know
Step 2 Prioritise what to measure
Step 3
Investigate and select energy management software and a long-term data storage solution
Step 4
Specify and select suitable meters and their communication system
Step 5
Develop a budget and implementation plan
DEVELOPING A GAS MEASUREMENT AND MONITORING PLAN
Step 1
Specify the goal and what you know
Set a primary goal
A primary goal encapsulates what you want to achieve and becomes the main driver for your project. Examples might be:
• accurately measure and monitor 80 % of gas energy used at the sub-process level
• accurately allocate costs to major process areas
• better allocate costs to tenants in a building
• measure the energy savings from a planned energy conservation measure.
Being specific will help determine the success and cost effectiveness of the project. Achievement of the goal may require short and long-term targets, involve several aspects of the business, cover only a part of the site or include specific actions for inclusion in a wide range of engineering projects.
Specify what is known
Once the main goal and the extent of the project are defined, list all existing gas-using equipment( including equipment that uses secondary services such as steam or hot water) and all existing meters. Estimate gas usage as accurately as possible( recognising that you are not likely yet to have all relevant gas measurement and monitoring equipment to do this).
A Sankey diagram helps to visualise the energy flows and communicate them to other site personnel. An example is shown in Figure 8.
Identify all existing meters
Use the diagram to identify the location of all existing meters( flow, pressure and temperature) on the gas network and other relevant flows. For each existing meter, refer to Appendix B and ask:
• What is the meter type( e. g. a flowmeter could be vortex, variable area, ultrasonic transit time or electromagnetic)?
• What is being measured( e. g. services, product flows)?
• Where is the meter physically located?
• Is there any record of its last verification or calibration? Is there a way to cross-check its operation( e. g. temperature gun, manual temperature or pressure gauges, engineering calculations)?
• Can the data from the meter also be used for process control, safety or other purposes?
• Is the meter connected to a SCADA system?
• Is the meter in an appropriate location( distances and pipe orientations vary according to the technology, e. g. for a flowmeter, minimum lengths of straight pipe are required upstream and downstream from the meter)?
August 2016 | www. hvacrnation. com. au | HVAC & R Nation | 15