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Solar Cooling in Australia: The Future of Air Conditioning?

Dr P. Kohlenbach, M.AIRAH, Solem Consulting and Dr M. Dennis, M.AIRAH, Centre for Sustainable Energy Systems, Australian National University.

ABSTRACT This paper gives an outlook on the current and future situation of solar cooling in Australia. It discusses the current potential of energy and greenhouse gas savings by using alternative solar air-conditioning technologies. Economics are discussed using a comparison of photovoltaic vapour-compression cooling against solar thermal cooling with an absorption chiller and a grid-connected reference chiller. It was found that at current economical conditions and under the given financial and technical assumptions, a solar thermal cooling system has a lower lifetime cost than a PV-based system. However, both systems have higher lifetime costs than a grid-connected conventional system. A sensitivity analysis on electricity price showed that solar thermal cooling is more economic than PV-based cooling until the electricity price exceeds $0.5/kWhel. A PV-based system becomes the most economic cooling alternative if the electricity price exceeds $0.55/ kWhel. Greenhouse gas emissions were found to be lowest for the PV-based system due to the excess power being generated over the lifetime. The solar thermal system saves approximately 75 per cent of the emissions of the conventional system.

INTRODUCTION is a poor return on this investment, and so little incentive to upgrade the network in this way. Solar cooling replaces electricity with heat from the sun as the source of energy to drive a cooling or refrigeration process. Solar This is leading to supply security issues also noted by NEMMCO. cooling technology largely comprises “off-the-shelf” heating, Solar cooling is a distributed form of peak electricity reduction ventilation and air conditioning (HVAC) components, which are and has the unique ability to offset loads at source, thus reducing generally mature technology. transmission requirements, and in particular, peak transmission requirements. Combining these technologies into integrated systems has been proven feasible worldwide (mainly Europe) but the industry is The large demand for AC in Australia, combined with the still in its infancy in Australia, despite Australia being uniquely economic problem of infrastructure support, provides a basis suited to the technology, with great solar resources and large air for consideration of alternative technologies. conditioning (AC) demand throughout the country. The east coast of Australia receives between six to nine hours of 1 currENT SITUATION sunshine a day, and an annual solar exposure between 1200-2400 The combination of good solar resource and a large air kWh/m2/a. This is more than sufficient for solar applications. conditioning market seems like a perfect match for solar cooling The residential air conditioning market in Australia is around and refrigeration applications in Australia. However, there are 800,000 units per year, and has increased significantly over only few solar thermal cooling systems installed in Australia. recent years. In 2000, 35 per cent of all Australian households At the time of writing there are three solar cooling systems in had air conditioning; in 2006 this number had doubled to operation and three systems under tender or construction, as around 70 per cent. The majority of these units are reversible shown in Table 1. wall-mounted split units. The discrepancy between the great potential and the small Commercial air conditioning and refrigeration using chillers is number of installations is easily explained when economics are a market of around 1,000 units per year, 80 per cent of which are taken into account. Residential solar cooling systems (5-15 kWr) dry-cooled. Together, residential and commercial refrigeration are exclusively imported from overseas and attract a considerably and air conditioning consumes approximately 20 per cent of the high price tag in Australia. With specific cost of approximately total electricity generated and contributes approximately 7 per $6,000-9,000/kWr they are an order of magnitude more cent to the country’s GHG emissions [2-4]. expensive than conventional split systems, which are available The increasing popularity of domestic vapour compression at about $600-$800/ kWr (both costs for installed system, air conditioning in Australia has resulted in peak electricity excluding GST) [6]. demand growing much faster than baseload demand, as noted by The situation is different for larger commercial or industrial NEMMCO [5]. applications (50-500 kWr). Economies of scale make larger units Transmission and distribution assets must be sized more economical, and the hours of operation are usually much on the peak current transmission, and that capacity greater in an industrial application compared to residential. However, is used for a small proportion of the time. Thus there other market barriers are also restraining the market in this segment.

32 Ecolibrium • DECEmber 2010 FORUM

Cooling In operation Location Solar field size Collector type Application capacity since

Ipswich, Qld 250 kWr 570 m2 Parabolic Trough 2009 Hospital

Logan City tbd tbd tbd Under tender Office building Council, Qld

Alice Springs, Scheduled for 230 kWr 630 m2 Parabolic Trough Art gallery NT late 2010

Sydney, NSW 175 kWr 165 m2 Parabolic Trough 2007 Factory

Wyong, NSW 7 kWr 20 m2 Evacuated tube 2009 Café

Scheduled for Newcastle, NSW 230 kWr 350 m2 Parabolic Trough Shopping mall mid 2010

Table 1. Overview on existing solar thermal cooling systems in Australia

1.1 market barriers 1.2 market opportunities The main market barriers for solar cooling in Australia have Recently the situation for solar cooling has improved. been identified as: [7, 8] Government measures towards intelligent use of energy, peak – Low electricity prices reduction and building upgrades have been implemented, as – Low-cost conventional air conditioning well as various funding programs for renewable energies. These include: – Cross-subsidy of conventional air conditioning system by all electricity customers who have to pay for network and − Implementation of time of use (ToU) metering for end users generation infrastructure (ordinary residences, not just high-consumption users), thus – Most components manufactured overseas and imported encouraging peak power savings. – Low number of installed systems − Building owners’ recognition for energy efficient systems (Green Star and NABERS programs). – System complexity – Professionals involved lack training and experience with solar − Renewable Energy Credits (RECs) for solar thermal hot water cooling systems – Australia’s large climatic variety makes it difficult for a − Possible implementation of tradable certificates for energy standardised solar cooling system to be implemented. saving activities (Energy Savings Certificates, ESCs, NSW There are no major unsolvable technical issues for the only). implementation of solar cooling. The main barrier for A solar cooling system will most likely generate hot water during implementation is economic, not technical. There are sufficient installations in Europe where the technology has been proven operation and therefore becomes eligible for RECs. Users can feasible but the low electricity cost and cheap conventional AC trade the RECs for electricity saved by a solar hot water and units in Australia make competition difficult. Nevertheless, cooling system at a rate of approximately $35/kWhel before tax. economics for solar cooling can become much more favourable These measures do not significantly influence the economics of for a range of building applications and locations with higher a residential solar cooling system but they make an impact on electricity cost, such as islands, remote locations and off-grid larger scale systems. applications. To help overcome the market barriers described above and support the introduction and market development of solar 2 ECONOMIC COMPARISON cooling in Australia, the Australian Solar Cooling Interest A competitive technology to solar thermal cooling is Group (ausSCIG) was founded in 2008 [21]. ausSCIG, an photovoltaic-based cooling using photovoltaic (PV) panels to AIRAH special technical group, is an industry group made generate electricity connected to a conventional air conditioner,. up of individuals who are interested in developing the solar cooling industry in Australia, with the aim of combating climate So far, this technology has been far too expensive due to the high change by reducing greenhouse gas emissions (GHG) from the cost for PV panels. Recent price drops of PV panels however have residential and commercial building sectors [7]. changed this and lead to the investigation presented in Figure 1.

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MW Production Cost per Watt C. Reference case: Grid-connected scroll 8,000 $30 type vapour-compression chiller

$25 6,000 Solar PV Pricing Grid C $20

4,000 PV Production $15 Scroll chiller

$10 2,000 $5

0 $0 80 86 96 97 98 99 00 01 02 03 04 05 06 07 08

Figure 1. Global PV production and PV panel price from 1980 – 2008 [20].

The price per Watt peak of photovoltaic panels was approx. $300/Wp in 1956. In 1980 the price had dropped to approx. Grid-connected scroll chiller (REF) $27/Wp and current panel prices are around $2/Wp (~$4/Wp Figure 2. Scenarios for comparison of solar cooling including installation). technologies [9–13]. Three scenarios have been compared to each other: The comparison in this paper is made for a commercial A. Solar thermal parabolic trough collectors and a double-effect system of 230kWr cooling capacity, this being a medium-sized absorption chiller industrial application for office buildings, shopping malls, art galleries, hotels and the like. The following general assumptions Concentrator Absorption have been made: Cooler − All three scenarios have been investigated for two different Receiver A climate zones: Zone 3 (eg Sydney/NSW) and zone 2 (eg Brisbane/Qld) in Australia. − Cooling is needed for eight hours/day over five months/year (in total 1200 hours/yr or 276 MWhth/yr). This has been Solar assumed conservatively for zone 3, most likely the Connections air conditioning demand will be greater in zone 2. − Heating/hot water is provided whenever cooling Hot is not needed. Water − No subsidies have been assumed for solar thermal cooling (no RECs, no ESCs, no carbon tax and the like.)

Solar thermal collectors and absorption chiller (STAC) Financial assumptions All Scenarios

B. Photovoltaic panels and a scroll type vapour-compression Lifetime of scroll chiller 12 yrs chiller Lifetime of absorption chiller, collectors 20 yrs PV panels B & PV modules

CPI (inflation rate) 2.5 % Scroll chiller Discount rate 8 %

1 Electricity cost 0.17 $/kWhel Annual escalation 2 % Hot rate electricity cost Water Natural gas cost $6/GJ Inverter Annual escalation 1 % rate natural gas cost Photovoltaic panels & scroll chiller (PVS) Table 2. Financial assumptions for NPV calculations

34 Ecolibrium • DECEmber 2010 FORUM

− No feed-in tariff has been assumed for photovoltaic power generation. − All three systems have been designed to provide 100% of the annual cooling load. The comparison was made by calculating investment and O&M cost and calculate the net present value (NPV) for a lifetime of 20 years. Table 2 shows the financial assumptions for NPV calculations. The system specifications are given in Table 3 and the costing in Table 4. Figure 2 shows the breakdown of system costs.

System assumptions STAC PVS REF Figure 3. Breakdown of system equipment and installation costs. Total cooling 230 230 230 power (kWr) It can be seen in Table 4 and Figure 3 that the solar thermal Average annual 1.1 4.0 4.0 cooling system (STAC) has the highest upfront investment cost COP chiller (–) of all systems; however, the PV-based system (PVS) is only about Heat required for $20k cheaper. The reference system (REF) is approximately 65% 209 — — cooling (kWth) cheaper than both the STAC and PVS systems. Electrical power The solar thermal system (STAC) uses parabolic trough required for cooling 15 58 58 collectors with an annual average efficiency of 55%. A hot (kWel) water storage tank of 5,000 litres is used as a buffer tank. The absorption chiller is an air-cooled double-effect chiller with an Solar thermal annual average COP of 1.1. The solar thermal system yield has 2 508 391 — collector/PV area (m ) been calculated using Meteonorm data for the two climate zones Backup system for gas gas [15] in a TRNSYS simulation. none 2 heating/hot water boiler boiler The PV modules in the PVS system have been assumed with an annual average efficiency of 14%. A degra¬dation of the module Table 3. System specifications for NPV calculations efficiency of – 15% over the 20-year lifetime has been assumed. The PVS system yield has been calculated using a zone-based Cost yield factor of 1.382 MWh/kWp/a for Sydney and of 1.536 MWh/ STAC PVS REF assumptions kWp/a for Brisbane, including a 15% loss due to annual self- shading of the panels [16]. Solar collectors/ $330,200 $301,440 — PV panel cost3 Excessive power generated by the PVS system is accounted for as net export to the grid. The scroll chiller is air-cooled and has 230 kWr an annual average COP of 4.0. For the reference (REF) system Chiller and $154,000 $119,600 $119,600 the same chiller as for the PVS system is assumed. No electrical air cooler cost storage has been assumed. Balance $69,200 $137,650 $65,650 of plant cost 3 rESULTS AND DISCUSSION Total $553,400 $558,690 $185,250 The lifetime cost calculations over 20 years lifetime (replacement equipment cost of scroll chiller in scenarios PVS and REF after 12 years) are Total engineering given in Figure 4 and Table 5. Greenhouse gas emissions are and installation $86,658 $60,882 $28,412 shown in Figure 5 and Table 6. cost4 It can be seen that the solar thermal cooling system (STAC) Total has significantly lower lifetime costs than the PV-based system $640,058 $619,572 $213,662 system cost (PVS) under the given assumptions. The cost difference between systems STAC and PVS is approx. $114k over 20 yrs. Specific $/kWr 2,783 $/kWr 2,694 $/kWr 929 The reference case (REF) has the lowest lifetime cost of all three system cost systems. Annual average $6,893 $3,981 $17,163 Greenhouse gas (GHG) emissions have been calculated over O&M cost the lifetime using indirect emission factors for consumption of Table 4. Cost assumptions for NPV calculations purchased electricity from the grid, Table 6. Emission factors for both NSW and Qld are given as 0.89 kg CO2-e/kWhel, emissions for natural gas have been assumed as 200kg CO2e/MWhth[17]. 1 Gas boiler efficiency was assumed at 85%. 2 Parabolic collectors have been assumed at $650/m2, the PV panels at $4.20/Wp. Exported electricity into the grid from the PV system has been 3 Cost estimates for installation and engineering have been taken from [14]. accounted for as emissions avoided using the same factors. It

DECEMBER 2010 • Ecolibrium 35 FORUM

can be seen that the reference case (REF) has the highest GHG emissions of all three systems. The solar thermal cooling system (STAC) has approx. 78% less GHG emissions than the reference system (REF) under the given assumptions.

Figure 5. Lifetime greenhouse gas emissions of all systems

It is obvious from the analysis that the lifetime cost difference between a solar cooling system (PVS and STAC) and a grid- connected cooling system (REF) is still quite large, despite the recent price drops in PV module price and collector cost. Figure 4. Lifetime cost of all systems However, the cost difference between a solar thermal system and a PV-based system is significant under the current assumptions. The PVS system has only 5% of the reference GHG emissions in Therefore it has been investigated which escalation in grid zone 3 (Sydney) and no operational GHG emissions in Zone 2. electricity price is required to make a PV-based cooling system This is due to the excess electricity generated over the lifetime, competitive with a solar thermal cooling system. Also, it has which makes its GHG emissions negative. The excess electricity been investigated at which electricity cost both solar driven generated in zone 2 (Brisbane) is slightly higher than in zone 3 cooling systems become competitive with the grid connected (Sydney) due to higher annual solar radiation in zone 2. scroll chiller system. Figure 6 shows the results.

NPV results STAC PVS REF

Lifetime cost (20 yrs) $631,879 $745,959 $443,098

Zone 2 (Brisbane) Difference to 143% 168% 100% reference case

Lifetime cost (20 yrs) $652,292 $764,767 $446,953

Zone 3 (Sydney) Difference to 146% 171% 100% reference case

Table 5. Results of lifetime cost calculations

GHG emissions GHG emissions STAC PVS REF

Lifetime GHG 317 -139 1410 emissions (t CO2e) Zone 2 (Brisbane) Difference to 22% -110% 100% reference case Lifetime GHG 332 81 1481 emissions (t CO2e) Zone 3 (Sydney) Difference to 22%% 5% 100% reference case

Table 6. Lifetime greenhouse gas emissions

36 Ecolibrium • DECEmber 2010 FORUM

Figure 6. Sensitivity analysis on electricity price to reach lifetime cost parity between reference and solar cooling systems.

A few conclusions can be drawn from Figure 8. At current The main opportunities for solar cooling are: conditions ($0.17/kWhel) solar thermal cooling (STAC) has a lower lifetime cost than PV-based cooling (PVS) in both zones. − Implementation of Time of Use (ToU) metering, thus In zone 2 (Qld) the STAC and PVS systems have an equal lifetime encouraging peak power savings cost at an electricity price of $0.47 /kWhel. The PVS system − Building owners recognition for energy efficient systems. has lower lifetime costs than the REF system at electricity price (Green Star and NABERS programs) higher than $0.50 /kWhel and the STAC system at electricity cost lower than $0.52 /kWhel. In zone 3 (NSW) the break-even − Implementation of a carbon trading scheme to include between STAC and PVS occurs at $0.55 /kWhel. Both STAC and for environmental externalities associated with electricity PVS have lower lifetime costs than the REF system at electricity generation. (Carbon pollution reduction scheme). prices higher than $0.55 /kWhel. − Renewable Energy Credits (RECs) for solar thermal hot water 4 summary AND OUTLOOK systems Solar cooling is still a niche technology in Australia, despite good − Implementation of tradable certificates for energy saving solar resources and a large air conditioning and refrigeration activities (Energy Savings Certificates, ESCs, NSW only) market. Mostly economic, multiple market barriers prevent the It was found that at current economical conditions and under technology from achieving bigger market shares. This paper the given financial and technical assumptions, a solar thermal summarises the market barriers and opportunities for solar cooling. cooling system has a lower lifetime cost than a PV-based It further investigates the economics of a solar thermal, a PV-based system. However, both systems have higher lifetime costs than and a conventional cooling system over a 20-year lifetime. a grid-connected conventional system. A sensitivity analysis The main market barriers for solar cooling in Australia are: on electricity price showed that solar thermal cooling is more – Low electricity prices economic than PV-based cooling until the electricity price reaches approx. $0.50/kWhel. A PV-based system becomes the – Low-cost conventional air conditioning most economic cooling alternative if the electricity price exceeds – Cross subsidy of conventional air conditioning system by $0.55/ kWhel, beating the reference and solar thermal system in all electricity customers who have to pay for network and lifetime cost. generation infrastructure Greenhouse gas emissions were found to be lowest for the PV- – Most components manufactured overseas and imported based system due to the excess power being generated over the – Low number of installed systems lifetime. The solar thermal system saves approx. 78% of the emissions of the conventional system. – System complexity The authors acknowledge that the results of this study are subject – Professionals involved lack training and experience with solar to the modelling assumptions and to some degree a snapshot in cooling time. Changes in PV panel cost will influence this study as well – Australia’s large climatic variety makes it difficult for a as changes in investment cost for solar thermal collectors and standardised solar cooling system to be implemented. absorption chillers.

DECEMBER 2010 • Ecolibrium 37 FORUM

7. Kohlenbach, P. (2009). The Australian Solar Cooling Industry Group. Proc. 5 NOMENCLATURE of 3rd Int. Conference on Solar Air-Conditioning, Palermo, Italy, Sep 2009. 8. Johnston, W. (2006). Solar Air Conditioning: Opportunities and Obstacles in Australia, ISS Institute Fellowship Report. Variables Subscripts 9. Thermomax (2008). www.thermomax.com. Last accessed Mar 6th 2008. 10. Research Institute for Sustainable Energy (2009). www.rise.org.au. Coefficient of Last accessed Oct 19th 2008. COP th Thermal performance 11. ECVV (2009). http://upload.ecvv.com. Last accessed Oct 19th 2008. 12. Energy Conservation Systems (2008). www.ecsaustralia.com. Consumer Last accessed Oct 19th 2008. CPI el Electrical price index 13. Alliance for Responsible Energy Policy (2009). www.stopgreenpath.com. Last accessed Oct 22nd 2009 Greenhouse 14. Parsons Brinckerhoff (2008). Solar Power Plant Pre-Feasibility Study, prepared GHG r Refrigeration for ACTEWAGL and the ACT Government. http://www.cmd.act.gov.au. gas Last accessed 19/10/2009. Air- 15. Meteonorm (2009). Global Meteorological Database, Version 6.1. AC p peak 16. Office of the Renewable Energy Regulator (2009). RET process for Owners of conditioning Small Generation Units (SGUs), accessed online at http://www.orer.gov.au, 19/10/2009. PV Photovoltaic 17. Dept. of Climate Change, Australia (2009). National Greenhouse Accounts (NGA) Factors. Published June 2009. 18. North Carolina State University (2007). A journey through Africa, Asia and the 6 REFERENCES Pacific Realm. Gibbs Smith Publishing, Utah, U.S. 19. CSIRO Energy Technology, Newcastle. Private communication, 2008 1. Australian Bureau of Meteorology (2009). http://www.bom.gov.au. 20. Solar Buzz, company report. Green Econometrics Research, www.greenecon.net. Last accessed Oct 19th 2009 Last accessed Apr 9th 2010. 2. JARN (2009). Japan air-conditioning, heating & refrigeration news. 21. Australian Solar Cooling Interest Group (ausSCIG). www.ausSCIG.org. Special Edition May 25 2009. JARN Ltd., Tokyo, Japan. Last accessed Apr 9th 2010. 3. Energy Strategies (2007). Cold Hard Facts. The refrigeration and air-conditioning industry in Australia. http://www.environment.gov.au. Last accessed Oct 19th 2009. 4. JARN (2008). Japan air-conditioning, heating & refrigeration news. Special About the authors Edition November 25 2008. JARN Ltd., Tokyo, Japan. 5. National Electricity Marketing and Management Company (2008). Australia’s Dr Paul Kohlenbach, M.AIRAH, is directior of Solem Consulting. National Electricity Market, Statement of Opportunities, accessed online at Contact him at [email protected] http://www.aemo.com.au, 19/10/2009. Dr Mike Dennis, M.AIRAH, is a senior research fellow at the Centre for Sustainable Energy 6. Jakob, U. (2009). Solar Cooling in Europe. Proc. of Australian Solar Systems, Australian National University. Contact him at [email protected] Cooling Interest Group Conference, Newcastle, Australia. May 2009.

BEST HVAC Hygiene PRACTICE GUIDELINES

HVAC HYGIENE

AIR AH 1.8.4. BEST PRACTICE GUIDELINES Unusual contamination HVAC systems and components any unusual contamination event such as event 1.10.2. AIR AH any renovation/building activit should be inspected after BEST PRACTICE GUIDELINES Best practice HVACRecords hygien events are assessed in accordance ies. Unusual a contami fire or flood or building and system document operation and maintenancee management requires goo with 2.5 of this Guideline.nation ation including up to date system drawings showing access p d 1.9. system commissioning data. manuals, acc HVAC urate as installed HVAC HYGIENE Where HVAC systems or compon restoration oints and original HVAC HYGIENE adequately cleaned they should b The building owner should ma ents cannot be conducted HVAC Hygiene Insp ELINES intain records of any e repaired or replaced. with records of any cleaning or AIR AH BEST PRACTICE GUID 1.10. system hygiene verification carr ection Reports along ELI NES Best inspections. Maintaining these remedial works and BEST PRACTICE GUID practice profile of a building or syst ied out as a result of suchany AIR AH Water damage to hygiene HVAC hygiene management. records builds up urce of moisture 2.5.7. em over time that assists in s and components subjected a hygiene HVAC HYGIENE In particular the presence andh so in the system should All HVAC system surface to determine salvage management In addition, any reports relating to ind supporting any mould growt water damage should be evaluatedestoration activity. In 1.10.1. assessments or any energy rDs be identified and prevented. ability and likely success of anyion r should be investigated for Principles also be retained with these records. oor air quali EnE sTAnDA particular any internal insulat Best practice HVAC hygien manageme ty sysTEM hygi ally is covered in the World or fungal growth. nt reports should ccEpTABLE level evidence of water logging through the implementation of a few r MiniMuM A Mould in buildings more (WHO) gener Guidelines for Indoor Air TABLE 2.3 Minimum hygiene ucts deemed salvageablemanagement practices. e management ca ent (See Table 2.1) Health Organisation 1.11. Any system components or d and free from microbial n be achieved HVAC System or Compon Quality, Dampness and Mould. • elatively simple HVAC cation. (See 1.6) Clean should be thoroughly cleaned or water logged insulation Filter maintenance – Filters are standards HVAC system Classifi against dust and particulates. Sy (See 1.5) growth. Any water affecteded. and AHU be regularly inspected and maintathe primary def The primary design standards for H Clean 2.5.4. Asbestos products should be replac regulations re producing on by asbestos dust or fibresed. If is accordance with the requir stem fil ence 1668.2 which deals with ventilatio Supply system – moistu If HVAC system contaminati o condensation within the ters should equipment mples should be taken and analys Any water damage due t and AIRAH DA19 on HVAC&R ined, at least in outdoor air, location of intakes VAC Clean suspected then sa be assessed and the cause of the ements of AS/NZS systems are AS contamination is confirmedtent the system also needs to and mitigated. system assessment sh and AS/NZS 3666.1 which deals withn requirements (minimum 2 ate the presence of asbestos filter specifications to deter maintenance. The3666.2 initial and discharges, exhau Air intakes and exhausts Pre Filtration – Moder decontaminated by compe condensation identified ould include a review of the System entire system should be is optimal for the HVAC system, i AS/NZS 1668.1 details requirem microbial control.st rates) Supply air system, or Post Filtration – Light mine if fi persons. Any water leaks (pipes, building structure) need totype, be filter rating, system airflow lter application control associated with mechan d prior to undertaking any HVAC ents for fire and Return air system, or No Filtration – Light to asbestos inspection identified and repaire likely contaminant profile and th ncluding the filter use systems on of a HVAC system due he work. The primary standard for HVA smoke general Outside air system Decontaminati ivity that is outside t cleaning or restoration of installation and maintenan and pressure, the ical ventilation systems. Moderate Note: a specialised act maintenance is AS/NZS 3666.2. Its pr and contamination is information on the selection and applie general quality Exhaust air system deline. damage ce. Comprehensive control of microbiological contaminC systems oper Light scope of this Gui smoke assessment filters is provided in AIRAH DA15. Fire and sp. in building water and air ha ation and /c ontaining materials are found 2.5.8. imary focus Non-ducted refrigerated a Light ts subjected to• heatManagement or smoke of moisture – moisture manacation of air If potentially friable asbestos c should be shut down, focuses on general HVAC hygiene. ants such as Legionis the All HVAC system componen e their integrityis critical and likelyfor minimising the potential ndling systems but it also 2.1. Evaporative coolers Hygiene Clean within a HVAC system, the systeml should be removed by should be evaluated to determinity. In particularcontamination all fire and and any spills, l The standard covering the maintena ella the asbestos containing materia and alternative insulation success of any restoration activ gement AHU ric duct mountedsystems heaters or components should be d for fungal smoke control features of HVAC systems levels licensed asbestos removalists smoke dampers and all elect Clean ce. This includes the insulation for purpose inspectedin accordance as soon as is practicableaks or wetting of HVAC nce of the fire and The descriptions listed in Table defined Supply system – moisture products installed in its pla d electric heaters if it is should be assessed for fitnessance protocols of AS 1851. AS/NZS 1668.1, AS1668.2 and AS/NZS 3666 2.2. • Inspection and assessment – All HVACried out and is AS 1851. system hygiene inspector with four hy Access producing equipment Clean board surrounding duct mounte with the survey and mainten 2 are called up in the Building Code of 2.1, provide the HVAC be periodically inspected and assessede. determine if cleaning is required when verified to contain asbestos. deemed unable to withstand referenced standards and are mandato Air intakes and exhausts Any components or surfaces with the recommendations of this Gu part 1 and part the minimum acceptable h giene levels to for Pre filtration – Light d be carried out in systems should territories of Australia. Apart from buildingAustralia as pr Access is required in orderinspection to insp l work shoul • in Table 2.3. assessed against Supply air system, or Post Filtration – Clean All asbestos remova nal Code of Practice proper mechanical cleaningplaced. and restorationAll porousClean, surfacesare restore beyond and verify hygiene level in accordance may be individual state specific occ imary ygiene standards as list Note: NOHSC:2002 – Natio le ry in all states and of all components and a representa accordance with d all other applicab salvage and should be re damage shouldor components be evaluated have been id ideline. safety legislation and regulations rel Return air system, or No Filtration – Clean oval of Asbestos an ents. legislation the ed internal surfaces of the HVAC ect the internal su use systems for the Safe Rem ations and requirem subjected to fire or smokeetention followingcleaning the and cleaning restoration work s that should be complied with as theyupational are health special overnment regul – once systems re 1.6.12. AS/NZS 3666 parts 1 and tive portion of rfaces Outside air system Moderate state and local g for friability and odour r bleimmediately should be replaced including verifyingentified the clean as contaminate operation and maintenance. ating to HVAC hygand provision of access for maintenance.systems as defined inthe process. Any areas assessed as friaely toof impart the restored odours system.to the hould be undertaken Exhaust air system Clean and contamination has d, relevant to bothiene 2 both require adequate Once all asbestos materials or resurfaced. Any materials lik laced. The selection and application of general d a/c VAC system should be • Good housekeeping – HVAC hygiene liness Hygiene Level TABLE Non-ducted refrigerate Clean been removed the entire H supply air stream should be rep by AS 1324 and minimum applicat 2.1 DEFINITION Inspections a giene level should be verified. a common sense approach to limit filtration of ventilation systems are Description nd cleaned and the system hye labelled as asbestos-free filters are cover 1. OF Evaporative coolers Any component surface exhibiting angenerating damageacceptable due activities condition to heat within a bu also requires HEPA filters are classified in AS 4260.ion requirements for th Clean HYGIENE The components should b stos register updated. responding to any unusual contamination e ed LEVELS like may have exposure should be restored toould be given to any residual ing contaminant specified in AS 1668.2. No visible dust, debr ng theatres and the rocessing and the hazardous materials/asbe Even everyday tasks such as cleaningilding (vacuum and promptly e ean rooms, operati or replaced. Consideration sh in on the internal surfaces of It is not intended that the recommendati is or other contamination. lications such as cl odies, manufacturing/p 2. VAC special use app other governing b disinfecting), food preparation and Guideline conflict with the requirement Light Only slightly visible layer that certain H iene determined by or smoke residue that may remaf smoke residue can be highly d vent. It should be noted levels of HVAC hyg Deterioration the system. Certain types o and copying may be inadvertently int mandatory standards or with the req to no variations in density Note: s for higher 2.5.5. tual deterioration of the affecte ing, ons of this of fine general dust consistent ove specific requirement . s unacceptable contaminants into th document printing Commonwealth, State or Territory regulat Component surface remains v ns and the like ers and operator surfaces corrosive and 12lead to even oke residues can also be e s of any of these . activities, regulatio System own tory non-porous roducing within HVAC systems. with the regula component surface. Some smcted by smoke, heat or smok uirements of any 3. Moderate r the component surface with lit at they are familiar erate. orous components are e HVAC system. Visible levels of general dus isible beneath the fine layer o should ensure th n which they op When the surface of non-p toxic. Any metal surfaces affed by competent persons to ion. on a system component he jurisdiction i ting particulates or odours to requirements of t residue should be evaluate l be achievable or effective. Component surface is still v tle If fungal contamination in or identifiable through visual deteriorated and contribu ersely affect the quality t with varying density and limite f dust. ed to be sent to a the air stream, or otherwise adv determine if restoration wil is suspected, but not readily ples should be taken for e system, restoration should water from fire suppression 4. Heavy High levels of visible dust isible in some areas beneath th Samples for fungal analysis ne of the air moving through th d areas of accumulated fine debris. assessment, then surface sammended procedures for taking testing and assessment, and Any components affected by in accordance with 2.5.7. other contamination that laboratory analysis. Recom mycological laboratory for th site. Details of sample be performed and inspection/crequired.leaning of all downstream , debris, fibres or any e fine dust but in isolated sections may not be. ontamination assessment are activities should be assessed Component surface is barel surface samples for fungal c identification as a fungal growent and analysis should be components carried out as cover the component. removal, transport, assessm renovation detailed in Appendix D. laboratory. of porous Building or y if not at all visible beneath the coordinated with the testing Deterioration 2.5.9. www.airah.org.au If a system or component has been confirmed, by may be helpful to 2.5.6. contamination. ytical assessment, to be and linings contamination Reference images for the four de visual observation or anal the affected system or Fungal species identification is a shift from the indoor surfaces to this contaminant category determine whether there n or lining materials Any HVAC system subject www.airah.org.au mould contaminated then decontaminated. . This is needed in determine the hygiene level of fined hygiene level When internal HVAC insulatio should be evaluated to system components shoulddiation be of a mould affected to the outdoor concentration risk assessment. Clear orated and traces of the mponents found to have are found to be deteri nd within the system ticulate debris greater s are provided in Appendix F. Decontamination or reme rtaken if a thorough order to perform a proper e building owner and the system. Any system or co insulation or lining product tedfou surfaces should be accumulated general dust and par system should only be unde has been undertaken and communication between th blished in order able 2.3 should be cleaned. components, the deteriora onents of the system than the levels specified in Tontamination encountered, assessment of the systemd on limited samples. the HVAC cleaner should be estafungal level following 17 restored and the affected compentire system inspected Depending on the type of c not an assessment base to determine an acceptable e HVAC system. 13 or should be cleaned and the due to mould cleaning and remediation of th ed as required. f a HVAC system is for contaminants and clean Note: Decontamination o sed activity that econtaminated and cleaned nation is a speciali d Territory microbial contami ideline. State an Once the system has beenshould d be verified, see Section 3. outside the scope of this Gu irements for the have specific requ the system hygiene level governments may amination trol of microbial cont reporting and con www.airah.org.au www.airah.org.au 16

AIRAH’s newly released HVAC Hygiene Best Practice Guidelines are available to purchase in hard copy. n Establishes the criteria for evaluating the internal cleanliness of HVAC system components n Clearly determines when cleaning is required, according to the building use n Describes the components of HVAC systems to be evaluated n Describes the types of contamination likely to be encountered and includes for post fire and flood damage assessments n Specifies minimum inspection frequencies for various HVAC systems and components for scheduled maintenance programs

38 OrderEcolibrium your • copyDECEmb onlineer 2010 at www.airah.org.au or email [email protected]