EcoMesh Precooling System Reduce ru running cos osts an and ri risk of of HV HVAC C fail ailure du during hot hot wea eather 1 HVAC normal operating conditions 2 Hot weather events cause HVAC failures 3 HVAC industry response 4 Improve coil operating conditions 5 EcoMesh Precooling System 6 EcoMesh Case Studies 7 Planning an EcoMesh installation 8 Comparison with other precooling methods 9 Additional inner mesh for Transverse coils 10 Maintenance Requirements SBH SOLUTIONS 1
1 HVAC normal operating conditions Air cooled condensers remove the heat from inside the building and reject it to the outdoors. Chillers and refrigeration units operate best when: • Sized correctly for the building load • Air handling is optimised for the occupants • Installed to the manufacturer's specs • Have adequate exhaust air clearance • Operate in the design conditions (ambient temperature rarely goes above 40°C) • Expected life cycle is up to 20 years HVAC systems are designed to provide cooling capacity for normal operating conditions. When sized correctly, HVAC systems perform well in all weather conditions. SBH SOLUTIONS 2
1 HVAC normal operating conditions Typical example for a Carrier 30GK245 12 fan chiller with 725 kW nominal cooling capacity. Carrier 30GK245 12 fan chiller with nominal capacity 725 kW cooling, Chiller pumps chilled water into building … LWT (Leaving Water Temperature) set at a nominal 7 °C Carrier 30GK245 - with 12 fans SBH SOLUTIONS 3
1 HVAC normal operating conditions Typical cooling capacities - table LWT - leaving water temperature at a nominal setting of 7 °C • Nominal capacity 725 kW cooling • Compressor input power 279 kW Each degree rise in ambient • Unit input power 313 kW temperature reduces cooling capacity and increases power demand. SBH SOLUTIONS 4
1 HVAC normal operating conditions Typical cooling capacities - graphed kW Cooling capacity reduction between 30C and 45C: Cooling capacity reduces … 773 to 629 kW ( -19%) Cooling Compressor load increases … 265 to 304 kW (+15 %) Capacity COP reduces … 2.92 to 2.07 ( -29%) Each degree rise in ambient temperature reduces Compressor cooling capacity and increases power demand. Input power At 43C At 40C At 36C At 33C 299 kW 292 kW 282kW At 30C 273kW At 27C 265kW 256kW HVAC problems are revealed when building load exceeds cooling capacity - usually during a hot weather event!! Air-on condenser SBH SOLUTIONS 5
2 Hot weather events cause HVAC failures Every summer, hot weather event cause HVAC failure and expensive consequences! Deserted shops Prison cell evacuation Unproductive staff Hospital evacuation And power bill shock Data centre shutdown SBH SOLUTIONS 6
2 Hot weather events cause HVAC failures Most Australian cities experience hot weather events of 35° C or over … summer is the HVAC industry’s busiest season!! Maitland - maximum temperature days 32 Canberra - maximum temperature days 18 30-34 35-40 40+ "hot days" 30-34 35-40 40+ "hot days" Nov-16 8 4 0 4 Nov-16 6 0 0 0 Dec-16 12 6 1 7 Dec-16 16 0 0 0 Jan-17 6 6 6 12 Jan-17 13 12 0 12 Feb-17 10 4 5 9 Feb-17 8 4 2 6 Melbourne - maximum temperature days 9 Sydney - maximum temperature days 22 30-34 35-39 40+ "hot days" 30-34 35-40 40+ "hot days" Nov-16 2 1 0 1 Nov-16 4 3 0 3 Dec-16 7 1 0 1 Dec-16 9 4 0 4 Jan-17 4 4 0 4 Jan-17 5 8 3 11 Feb-17 4 3 0 3 Feb-17 6 1 3 4 Dubbo - maximum temperature days 49 Wagga - maximum temperature days 28 30-34 35-40 40+ "hot days" 30-34 35-40 40+ "hot days" Nov-16 14 2 0 2 Nov-16 9 1 0 1 Dec-16 15 12 0 12 Dec-16 19 4 0 4 Jan-17 11 13 6 19 Jan-17 11 13 3 16 Feb-17 9 8 8 16 Feb-17 13 5 2 7 Source: BOM data for 2016/17 SBH SOLUTIONS 7
2 Hot weather events cause HVAC failures Main reasons for HVAC failure: Building load creep - the condensers no longer sized correctly for the load Older HVAC plant - condenser can’t Incorrectly configured HVAC plant cope and trip out above 35 C Hot roof scenario - the roof top is actually Post installation building modifications Peak power demand may cause load 5-10C hotter than the design condition - recirculating air reduces heat rejection shedding of individual units SBH SOLUTIONS 8
3 HVAC industry response Option 3: Replace the units half way Option 1: Emergency call out by Option 2: HVAC Optimisation to through their service life … technicians to reset the system … improve HVAC performance: eg • Start - Stop programming • Space temp. setpoints • Master air handling • Staging of compressors • Coil cleaning etc But if the system is unmodified, the An expensive and inconvenient scenario! next hot weather event will require additional call outs … sometimes multiple times in day or even weeks But if condensers cannot reject sufficient heat, then any adjustments would be futile. A less common approach is Option 4 . . . improve the operating conditions of the condenser coils!! SBH SOLUTIONS 9
4 Improve coil operating conditions Referring to the cooling capacities chart … 30- 50% of a building’s electricity demand is for A simple method to improve efficiency is to refrigeration or air conditioning. improve coil operating conditions by lowering the air-on coil temperature … Give the coils a “cool change” during hot weather events!! Efficiency gains in the HVAC system will reduce the building’s energy cost … especially during hot weather events. Pre-cooling alters the micro-climate outside the chiller, to lighten the compressor load and reduce running costs. A lower air-on temperature, increases cooling capacity and reduces input power ... SBH SOLUTIONS 10
4 Improve coil operating conditions Pre-cooling the air on coils flattens the performance curves during hot weather. kW The unit operates in an environment where the temperature never rises above 35C. Cooling Capacity Overall effect is to lighten the refrigeration cycle increases and prolong the life of the HVAC plant. Typical performance curves with precooling. Compressor Input power decreases Air-on condenser SBH SOLUTIONS 11
5 EcoMesh Precooling System EcoMesh introduced into Australia in 2014 but has over 20 years in Europe, India and the Middle East! Extract from published paper, 12 th International Congress on EcoMesh owner, Mr Zafer Ure. Sustainable Energy Technologies, 26-29 th August 2013, Hong Kong Mr Zafer Ure has nearly 30 years of engineering experiences as a consultant, senior design engineer and Sales Manager for PCM Products Ltd and EcoMesh Ltd. SBH SOLUTIONS 12
5 EcoMesh Precooling System EcoMesh also the adiabatic solution for Heatcraft and Trane in Europe Heatcraft Europe: Adiabatic solution by EcoMesh - panels and sprayers Trane Europe: Adiabatic solution by EcoMesh kits and controller Source: www.ecomesh.eu SBH SOLUTIONS 13
5 EcoMesh Precooling System Trane ECGAM Emicon RAE Ballarat Hospital Data Centre Adelaide EcoMesh in Australia - since 2014 York YVAA York YLCA Fujitsu Sydney Queen Elizabeth Hospital York YLAA Port Pirie Hospital Temperzone OPA410 City X Adelaide Carrier Aquasnap Carrier 30RB Netley Police Station St Kilda Town Hall, Melbourne C Space building Adelaide Canberra SBH SOLUTIONS 14
5 EcoMesh Precooling System EcoMesh precooling process Water evaporates off the mesh to Water sprayers wet the inside of the Mesh panels are installed outside the cool the incoming air. mesh for a few seconds every 30 secs condenser coils. Mesh panels also protect the coil from “Adiabatic cooling” improves system COP Air flows freely through and around solar radiation, hail stones and other air and minimises risk of head pressure trips the mesh panels. borne debris in summer. EcoMesh has a patented For most of the year, mesh in coarse outer net (for Temperatures above 30C structural support) and a front of coils has a negligible occur for only a short time fine inner mesh (for impact on the chiller fan load. during summer months. capturing water drops). SBH SOLUTIONS 15
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