CAS Audit Guidelines and Standards

The Electricity Commission has produced several guidelines and standards for use by accredited CAS auditors. These are available on the Commissions website.

The In-depth CAS Audit Reporting Standard is used as the benchmark against which the report included in an application for CAS auditor accreditation is compared with.

Types of CAS Audits

Two types of CAS audit are accommodated under the Electricity Commission’s programme:

A ‘Walk-thru CAS assessment’ to identify and estimate the value of CAS efficiency opportunities on a site. The level of detail collected is adequate largely only to identify areas of priority and determine the need for a more detailed audit.  Click here for more details on the Walk-thru CAS assessment.

An ‘in-depth CAS audit’ collects more detailed information and operating measurements from  the compressed air system. This type of CAS audit will not only identify the energy-saving measures appropriate for the compressed air system, but also quantify the costs and benefits sufficiently to enable sound investment decisions to be made. Click here for more details on the In-depth CAS Audit.

Electricity Commission Funding for CAS Audits

As part of its Compressed Air Systems Electricity Efficiency programme, the Electricity Commission has funding available for Walk-thru Assessments and In-depth Audits and, in some cases, for CAS capital investments.  Details of how to access the funding and other conditions are available through the Commission’s website.

ECCA Energy Audit Grants

EECA’s Energy Audit Grants scheme is separate from the Commission’s funding of CAS audits, and considers a broader range of energy efficiency issues. However, if you are considering a broader review or audit of the energy efficiency of a business, there may be an opportunity to have the specific CAS audit linked into a wider audit performed under the EECA Grants scheme.

If that is the approach you prefer please make that known to your EECA account manager. You can find out more about EECA Energy Audit Grants here.

Sources of useful CAS Information

NZ Compressed Air System Information

International Compressed Air Systems Web-sites and Resources

Compressed Air Challenge - The Compressed Air Challenge is a voluntary collaboration of industrial users; manufacturers, distributors and their associations; consultants; state research and development agencies; energy efficiency organizations; and utilities.  This group has one purpose in mind - helping users enjoy the benefits of improved performance of their compressed air systems. The mission of the Compressed Air Challenge (CAC) is to develop and provide resources that educate industry on the opportunities to increase net profits through compressed air system optimization.

The CAC has already developed a series of training sessions to help users learn more about the fundamentals of compressed air systems. A sourcebook and fact sheets and tip sheets are also available as listed below.

CAC Fact Sheets

CAC Tip Sheets

See here for CAC and a range of other Case Studies.

More details at:  http://www.compressedairchallenge.org/

The British Compressed Air Society (BCAS) - The British Compressed Air Society was founded in 1930 at the instigation of the British Government. It is an organisation open to manufacturers, distributors and end users of compressed air products and services.  Society and its members have the following aims:

  • To promote the use of safe and reliable power
  • To improve the services they offer industry
  • To encourage and help members to develop their professional competence.
  • To bring the experience of members to bear on the conduct of business in industry for the common good.

The Society actively represents the interests of members and the compressed air industry to both United Kingdom Government, European and overseas Institutions.  More details at: http://www.bcas.org.uk/

Key Compressed Air Documents

Sector specific Guides produced by the Society are available for purchase and include:

  • Dental Compressed Air Code Of Practice - Guidance produced in partnership with the dental industry to ensure a dental surgery’s compressed air installation complies with current legislation. Aimed at suppliers, installers and dentists themselves. It specifies the same level of air purity as HTM2022 but redefines installation requirements since these need not be as rigorous as for dental units in hospital environments.
  • Food Grade Compressed Air - Until the issue of this document in conjunction with the British Retail Consortium, there were no controls governing the use of compressed air for food producers. The Code will assist food producers to comply with the 852/2004 EU Regulation and can be used in conjunction with the HACCP process. The code specifies contamination levels (water content, microbiological and solid particles and total oil presence) for compressed air that comes into both direct and indirect contact with food. Auditing, monitoring and test methods to determine quality levels are included.
  • Installation Guide (5th Edition) - The essential guide to the specification, selection and installation of compressed air equipment.
  • Pressure & Leak Testing of Compressed Air Systems Code of Practice - This defines best practice for jointing techniques, integrity testing (including risk assessment), pressure decay testing and staged pressure testing. Following these guidelines will reduce the susceptibility of your compressed air system to develop leaks, thereby increasing energy efficiency, reliability and safety.
  • Tools Guide (1st Edition) - A5 handbook for users of all types of pneumatic tools, complete with typical application, service line installation, legislation, standards, publications and air consumptions.


The Compressed Air Association of Australasia (CAAA) - The Compressed Air Association of Australasia (CAAA) is a division of the Air & Mine Equipment Institute of Australasia (AMEI).  AMEI is a non-profit organisation and has operated since 1968. Membership is drawn from Australia and New Zealand compressed air & mine equipment companies and major suppliers of tools.

The CAAA web-site has a very valuable source of industry related articles in their ‘media’ selection. They have also produced a series of four brochures to explain the basics of compressed air systems and then, in more detail, to show how to save energy, reduce costs and help the environment

  • Overview of Compressed Air Systems
  • Compressed Air Systems-Selection and Efficient Production
  • Compressed Air-Efficient Utilisation
  • Compressed Air-Treatment

More details at http://www.compressedair.net.au/

The Carbon Trust – Compressed Air Guides and Factsheets
The UK based Carbon Trust has an extensive collection of Guides and Factsheets on Compressed Air on it web-site including:

  • GPG385 Energy efficient compressed air systems (March 2005) - Written by BCAS and its members for Carbon Trust, this guide identifies the main areas for energy savings: managing the air system, reducing misuse of air, the distribution network, compressor selection and control, air receivers, air treatment and condensate management. Included are a useful series of checklists. The potential for savings with minimal investment is up to 30%.  Download PDF
  • GIL123 Compressed air factsheet (June 2005) - This fact sheet provides an overview of compressed air systems and gives straightforward tips on reducing their running costs. It gives simple tips covering inspection, maintenance, and control to help improve their energy efficiency.  Download PDF
  • GPG241 Energy Savings in the Selection; Control and Maintenance of Air Compressors (August 1998) - This guide shows how to select, control and maintain plant to bring down the cost of generating compressed air. Guidance on plant selection is provided, and opportunities to reduce operating, energy and capital costs at the design stage. Small differences in plant efficiency can save far more than the initial difference in capital cost. The guide also covers necessary maintenance for long-term reliability and energy efficient operation.  Download PDF
  • GPG216 Energy Saving in the Filtration and Drying of Compressed Air (March 1998) - Treating compressed air considerably increases the energy costs. This guide provides advice on practical ways of improving the energy efficiency of filtration and drying operations, and selecting the level of treatment appropriate to the application. Details of associated energy costs and energy-saving opportunities are given for different equipment. It complements Energy Consumption Guide (ECG) 42, 'Compressing Air Costs - Treatment'.  Download PDF
  • FL0069a Everyone's Guide to Saving Energy in Compressed Air (July 2001) - This A6 booklet is an ideal introduction to energy efficiency in each of these areas and will be useful as part of a training programme or staff awareness campaign.  Download PDF
  • FL0036d Action Agenda sheet for Compressed Air (October 2000) - A flyer for managers of compressed air systems who want to take steps to save energy through the active involvement of their staff who use compressed air. It helps you set an action agenda for your staff to achieve these savings of 10% or more.  Download PDF
  • GPG 238 - Heat Recovery from Air Compressors (March 1998) - This guide offers advice on practical ways of recovering and utilising waste heat from air compressors. An outline procedure, illustrated with examples, is provided for assessing the likely benefits of recovering waste heat. Worked examples of some of the calculations involved are included.  Download PDF
  • GPG126 Compressing your air costs (March 1994) - This guide provides advice on practical ways of improving energy efficiency in plants generating and distributing compressed air. It considers how such systems can be monitored, and their demand reduced.  (Note - the pdf has been produced by Carbon Trust from scanned images. If the pdf is not the quality you require or the file size is a problem please call Carbon Trust on 0800 085 2005, (please do not call BCAS). This publication has now been replaced with GPG385 - Energy efficient compressed air systems.  Download PDF
    These Guides and Factsheets are available from the British Compressed Air Society web-site at: http://www.bcas.org.uk/carbontrust.asp

US Department of Energy – Compressed Air Resources
The US DoE website has a series of Guides, Tip Sheets and Technical Report available for download. Resources Include training details, how to choose a CAS provider and various assessments of the state of the CAS Market.

This Guide presents some of the inappropriate uses of Compressed Air and what the alternatives might be.

Works Management – UK Manufacturing and Engineering Trade Magazine
The Works Management website claims to be the definitive homepage for managers at every level and every size of plant throughout manufacturing industry.  It presents a series of questions and answers relating to the efficient use of Compressed Air Systems.

ResourceSmart Business – Victorian (Aus) Resource for Businesses
The ResourceSmart Business website offers a number of very useful Tables and Fact Sheets on Compressed Air Systems and their efficient use.

The Australian Department of the Environment and Heritage // Australian Greenhouse Office has produce a series of Audit Tools covering a range of aspects from Lighting and Lighting control to Chillers, Ventilation and Air-conditioning to Building insulation.  A total of 11 ‘Energy Audit Tools’ were produced with Compressed Air being Number 11.  The audit tools have been designed as a modular system. This means that they can be utilised as stand-alone independent units or in combination with the other units. The Energy Audit Tool - COMPRESSED AIR can be accessed here.

The Australian Greenhouse Office has produced a number of studies of relevance to compressed air.

  • Best Practice Program - This study looks at a range of options for a Best Practice Program for compressors. The study outlines programs in operation overseas and documents interviews with Australian stakeholders. [NAEEEC Report 2002/06].  Access the study here.
  • MEPS for Compressors? – This study concludes that MEPS are unlikely to be cost effective but recommends a range of voluntary programs such as improved maintenance and improved information programs.  Access the study here.
  • National Appliance and Equipment Energy Efficiency Program - Analysis of Potential for Minimum Energy Performance Standards for Packaged Air Compressors. Prepared for the Australian Greenhouse Office by Mark Ellis & Associates. Final Report, March 1st, 2001. Gives data on energy, performance and greenhouse gas emissions for compressors and investigates a range of program options including MEPS and voluntary programs and makes an initial assessment of their impact. Access the study here.

The Air and Mine Equipment Institute of Australia has produced a very useful Brochure giving an overview of Compressed Air Systems highlighting in particular types of systems, components of a system and what system may be right for you.  A Guide to design consideration, sizing, required pressure and air quality has also been produced.

The Canadian Industry Programme for Energy Conservation - has developed a simple Guide to improving efficiency for Compressed Air usage. 

Other Resources - Papers

Beyond Air Leaks - How to Do Compressed Air Systems Analysis? at http://www.unicade.com/Articles/AirComp.htm

If you know of other sources of CAS related information that could be added to these resources please contact the CAS Scheme Administrator with the details.

Compressed Air Calculators

Compressed air calculators are quick and easy ways for you to see what the potential savings may be achievable.

Calculator One - TThis calculator provides an indication of the potential savings achievable by repairing leaks, reducing system pressure and reducing inlet air temperature. Find out what you could save here.

Calculator Two – This calculator is a basic calculator.   Find out what you could save by making equipment changes here.

Calculator Three - This calculator can used to calculate the pressure drop in compressed air pipelines.   Find out what you could save here.

Compressed Air Systems Case Studies

NZ Case Studies

International Case Studies

Compressed Air Standards

Key Standards relating to compressed are as follows:

International Standard ISO 8573

A Guide to the ISO 8573 Series Compressed Air Quality Standard is available. 

TC 118 – ISO Technical Committee on Compressors and pneumatic tools, machines and equipment

The ISO Technical Committee TC118 has the following current work programme:

Code

Covers

TC 118/SC 1

Process compressors

TC 118/SC 3

Pneumatic tools and machines

TC 118/SC 4

Quality of compressed air

TC 118/SC 6

Air compressors and compressed air systems

The Electricity Commission has observer status for New Zealand in respect of the work covered by ISO/TC 118/SC 6. This includes work on ISO/CD 1101 relating to compressed air systems energy efficiency audit reporting.

Australian Standard for Small Air Compressors - Protocol 2000+

Protocol 2000+ was introduced in Australia to standardise the measurement of air compressors in order that consumers are able to select the most appropriate compressor for their application. 

Further details are available here and also here.