. Aircon Energy Saver Evaluation Report for SHUI ON DEVELOPMENTS.......... Report for the testing of the Aircon Energy Saver when installed on DX cooling equipment at Rainbow City, Shanghai, China Test duration June 1st 7th 26 Evaluation carried out for Shui On by Comford Resource Limited 28/F Tesbury Centre 28 Queens Road East Wanchai Hong Kong SAR China Tel: (852) 12 882
Executive Summary - Rainbow City, Shanghai Shui On Developments have identified and evaluated a means to reduce energy costs for their product purchasers, through the fitting of a UK designed microprocessor control system to the currently, and for the future, installed Air Conditioning equipment. The following report, describes exceptional savings in electricity consumption in the region of 6%, even when mitigating this headline saving value it has major benefits for enhancing the value and quality of property offered to potential and existing customers and also enhancing the corporate reputation and profile of Shui On when compared to any competitors. The enhancement of business returns through the reduction of built property energy costs in Air Conditioning has implications for Shui On business. In addition good corporate energy practice also demonstrates good corporate citizenship, and is in keeping with the company s Corporate management goals.
Aircon Energy Saver Evaluation Report for Shui On AES installed at Rainbow City, Shanghai, China Objective The objective of this report is to show the benefits of installing the AES to DX cooling equipment. The report will determine the level of savings achieved with the AES controlling the compressor. Determining the evaluation The evaluation will be completed on the basis of comparison. The existing cooling unit will be monitored with and without the AES, the cooling medium cycle is logged in the two states and compared to determine a percentage reduction. Equipment list The data logging equipment comprised of:- 1. HOBO 4-Channel Indoor Logger ( H8-7-2 ) with AC Current Transformer (CTV-B ) to measure the consumed amps 2. HOBO 4-Channel Indoor Logger ( H8-7-2 ) internal Temperature Sensor to measure the conditioned area temperature (return air).. HOBO 4-Channel Indoor Logger ( H8-7-2 ) internal humidity sensor to measure the conditioned area humidity (return air). Evaluation Air Conditioning Unit The equipment on which the trial was conducted was a Panasonic A1815kw split AC unit with 5.1kw cooling. This was a new installation in a brand new th floor empty apartment. The unit is of the standard packaged split type with separate indoor and outdoor units, controlled from a return air temperature controller that is supplied as an integral part of the complete unit. Testing criteria The logging equipment was installed to data record the operation of the DX unit. It monitored the temperature and the humidity of the conditioned area /F apartment living area. This is to show that the usual conditioned room temperature and humidity are not adversely affected. The current transformer was installed on the supply cable to the outdoor unit and will show the on and off periods of the compressor.
To provide a robust trial comparison and remove the influence of daily variations in outside ambient temperature and also variations between morning and afternoon the trial ran for a fixed period each day from 8 to 16 with AES control being switched off or on for a 4 hour period, the switching times being at 8: and 12 hours, the AES period of operation alternated for the following trial day, as illustrated in the following table; Day AES Operating AES Not Operating Day 1 8: 12: 12:1 16: Day 2 12:1 16: 8: 12: Day 8: 12: 12:1 16: Day 4 12:1 16: 8: 12: Day 5 8: 12: 12:1 16: Day 6 12:1 16: 8: 12: Day 7 8: 12: 12:1 16: Day 8 12:1 16: 8: 12: This provides a direct comparison between the AES in control mode where it makes savings, and in bypass mode where the DX unit operates as normal. The logging equipment sampling rate was set to 9 seconds (one minute and seconds) in every device, this value being set to give a continuous period of 8 days for the test. For the purposes of the test the AES was made operable and inoperable at the designated time events by a site based person nominated by Shui On.
Data Results ROOM TEMPERATURE The following graphs are of the daily logged temperature D a y 1 ( A E S O p d u r i n g A M ) 2 5 2 T e m 1 5 R e t u r n A ir T e m p e r a t u r e 1 5 6 / 1 / 6 8 : :. 6 / 1 / 6 8 : 1 5 :. 6 / 1 / 6 8 : :. 6 / 1 / 6 8 : 4 5 :. 6 / 1 / 6 9 : :. 6 / 1 / 6 9 : 1 5 :. 6 / 1 / 6 9 : :. 6 / 1 / 6 9 : 4 5 :. 6 / 1 / 6 1 : :. 6 / 1 / 6 1 : 1 5 :. 6 / 1 / 6 1 : :. 6 / 1 / 6 1 : 4 5 :. 6 / 1 / 6 1 1 : :. 6 / 1 / 6 1 1 : 1 5 :. 6 / 1 / 6 1 1 : :. 6 / 1 / 6 1 1 : 4 5 :. 6 / 1 / 6 1 2 : :. 6 / 1 / 6 1 2 : 1 5 :. 6 / 1 / 6 1 2 : :. 6 / 1 / 6 1 2 : 4 5 :. 6 / 1 / 6 1 : :. 6 / 1 / 6 1 : 1 5 :. 6 / 1 / 6 1 : :. 6 / 1 / 6 1 : 4 5 :. 6 / 1 / 6 1 4 : :. 6 / 1 / 6 1 4 : 1 5 :. 6 / 1 / 6 1 4 : :. 6 / 1 / 6 1 4 : 4 5 :. 6 / 1 / 6 1 5 : :. 6 / 1 / 6 1 5 : 1 5 :. 6 / 1 / 6 1 5 : :. 6 / 1 / 6 1 5 : 4 5 :. T i m e D a y 2 ( A E S O p e r a t io n a l P M ) 2 5 2 T e m p 1 5 1 R e tu r n A ir T e m p e r a tu r e 5 6 / 2 / 6 8 : :. 6 / 2 / 6 8 :1 5 :. 6 / 2 / 6 8 : :. 6 / 2 / 6 8 :4 5 :. 6 / 2 / 6 9 : :. 6 / 2 / 6 9 :1 5 :. 6 / 2 / 6 9 : :. 6 / 2 / 6 9 :4 5 :. 6 / 2 / 6 1 : :. 6 / 2 / 6 1 :1 5 :. 6 / 2 / 6 1 : :. 6 / 2 / 6 1 :4 5 :. 6 / 2 / 6 1 1 : :. 6 / 2 / 6 1 1 :1 5 :. 6 / 2 / 6 1 1 : :. 6 / 2 / 6 1 1 :4 5 :. 6 / 2 / 6 1 2 : :. 6 / 2 / 6 1 2 :1 5 :. 6 / 2 / 6 1 2 : :. 6 / 2 / 6 1 2 :4 5 :. 6 / 2 / 6 1 : :. 6 / 2 / 6 1 :1 5 :. 6 / 2 / 6 1 : :. 6 / 2 / 6 1 :4 5 :. 6 / 2 / 6 1 4 : :. 6 / 2 / 6 1 4 :1 5 :. 6 / 2 / 6 1 4 : :. 6 / 2 / 6 1 4 :4 5 :. 6 / 2 / 6 1 5 : :. 6 / 2 / 6 1 5 :1 5 :. 6 / 2 / 6 1 5 : :. 6 / 2 / 6 1 5 :4 5 :. 6 / 2 / 6 1 6 : :. T im e D a y ( A E S O p e r a t i o n a l A M ) 2 5 2 T e m p 1 5 1 R e t u r n A ir T e m p e r a t u r e 5 6 / / 6 8 : :. 6 / / 6 8 : 1 5 :. 6 / / 6 8 : :. 6 / / 6 8 : 4 5 :. 6 / / 6 9 : :. 6 / / 6 9 : 1 5 :. 6 / / 6 9 : :. 6 / / 6 9 : 4 5 :. 6 / / 6 1 : :. 6 / / 6 1 : 1 5 :. 6 / / 6 1 : :. 6 / / 6 1 : 4 5 :. 6 / / 6 1 1 : :. 6 / / 6 1 1 : 1 5 :. 6 / / 6 1 1 : :. 6 / / 6 1 1 : 4 5 :. 6 / / 6 1 2 : :. 6 / / 6 1 2 : 1 5 :. 6 / / 6 1 2 : :. 6 / / 6 1 2 : 4 5 :. 6 / / 6 1 : :. 6 / / 6 1 : 1 5 :. 6 / / 6 1 : :. 6 / / 6 1 : 4 5 :. 6 / / 6 1 4 : :. 6 / / 6 1 4 : 1 5 :. 6 / / 6 1 4 : :. 6 / / 6 1 4 : 4 5 :. 6 / / 6 1 5 : :. 6 / / 6 1 5 : 1 5 :. 6 / / 6 1 5 : :. 6 / / 6 1 5 : 4 5 :. 6 / / 6 1 6 : :. T i m e
D a y 4 (A E S O p e ra tio n a l P M ) 2 5 2 1 5 T e m p R e tu rn A ir T e m p e ra tu re 1 5 6/4/6 8::. 6/4/6 8:15:. 6/4/6 8::. 6/4/6 8:45:. 6/4/6 9::. 6/4/6 9:15:. 6/4/6 9::. 6/4/6 9:45:. 6/4/6 1::. 6/4/6 1:15:. 6/4/6 1::. 6/4/6 1:45:. 6/4/6 11::. 6/4/6 11:15:. 6/4/6 11::. 6/4/6 11:45:. 6/4/6 12::. 6/4/6 12:15:. 6/4/6 12::. 6/4/6 12:45:. 6/4/6 1::. 6/4/6 1:15:. 6/4/6 1::. 6/4/6 1:45:. 6/4/6 14::. 6/4/6 14:15:. 6/4/6 14::. 6/4/6 14:45:. 6/4/6 15::. 6/4/6 15:15:. 6/4/6 15::. 6/4/6 15:45:. 6/4/6 16::. T im e The graph below shows the temperature profile for the entire test period Entire Test Period 25 2 15 Return Air Temperature1 1 5 8::. 19:15:. 6/2/6 6::. 6/2/6 17:45:. 6//6 5::. 6//6 16:15:. 6/4/6 ::. 6/4/6 14:45:. 6/5/6 2::. 6/5/6 1:15:. 6/6/6 ::. 6/6/6 11:45:. 6/6/6 2::. 6/7/6 1:15:. 6/7/6 21::. 6/8/6 8:45:. 6/8/6 2::. 6/9/6 7:15:.
ROOM HUMIDITY Entire Test Period Room Humidity 9 8 7 6 %rh 5 4 Return Air Humidity 2 1 8::. 18:19:. 6/2/6 4:9:. 6/2/6 14:58:. 6//6 1:18:. 6//6 11:7:. 6//6 21:57:. 6/4/6 8:16:. 6/4/6 18:6:. 6/5/6 4:55:. 6/5/6 15:15:. 6/6/6 1:4:. 6/6/6 11:54:. 6/6/6 22:1:. 6/7/6 8::. 6/7/6 18:52:. 6/8/6 5:12:. 6/8/6 15:1:. 6/9/6 1:51:. 6/9/6 12:1:. Time
COMPRESSOR DATA Typical Graph over 4 hours with the AES not operating 18 16 14 12 1 8 6 4 2 12::. 12:24:. 12:48:. 1:12:. 1:6:. 14::. 14:24:. 14:48:. 15:12:. 15:6:. 16::. Typical Graph with the AES operating Current (Amps) c:* 18 16 14 12 1 8 6 4 2 8::. 8:24:. 8:48:. 9:12:. 9:6:. 1::. 1:24:. 1:48:. 11:12:. 11:6:. 12::. It can clearly seen by comparing the graphs the reduced run time of the compressor
Summation of Logged Data When the compressor operational logged data file is exported to an excel spreadsheet file, this excel file is evaluated and can be summated and tabulated as shown below. The table represents the running cycles for the compressor during the test cycle periods. Compressor on is taken as a current value greater than.7 amp (.6 amps being the baseline ( off ) value). The actual current when the compressor is on has a minimum value of 1.9 amps rising to a maximum of 17 amps. To generating the following table the on or off data log points from within the applicable test cycle period are totalled and documented as shown below; SWITCHING SUMMARY COMPRESSOR OPERATION DURATIONS WITH AES OPERATING WITH AES NOT OPERATING.(OFF) Units = Log points Units = Log points Day Duration ON OFF TOTAL ON OFF TOTAL 1 8am-12pm 5 17 16 Off ratio = 66.87% 1 12pm-4pm 142 18 16 Off ratio = 11.25% 2 8am-12pm 17 2 16 Off ratio = 14.7% 2 12pm-4pm 5 11 16 Off ratio = 68.75% 8am-12pm 47 11 16 Off ratio = 7.62% 12pm-4pm 12 4 16 Off ratio = 25.% 4 8am-12pm 11 47 16 Off ratio = 29.7% 4 12pm-4pm 47 11 16 Off ratio = 7.62% 5 8am-12pm 47 11 16 Off ratio = 7.62% 5 12pm-4pm 11 47 16 Off ratio = 29.7% 6 8am-12pm 117 4 16 Off ratio = 26.87% 6 12pm-4pm 49 111 16 Off ratio = 69.5% 7 8am-12pm 46 114 16 Off ratio = 71.25% 7 12pm-4pm 1 16 Off ratio = 18.75% 8 8am-12pm 121 9 16 Off ratio = 24.7% 8 12pm-4pm 46 114 16 Off ratio = 71.25% Test Total 85 895 128 99 287 128 Total Off % 69.92% 22.42% Total ON %.7% 77.57% NOTE: each log point represents 9 seconds Test assessment The prevailing operating conditions during the period of the test can be considered to be a typical of days for time of year and for the site, equipment, and application. The only exception to be noted for the test is the absence of any furniture or occupants and the consequent heat gains; however, the equipment is located within the normal living space of the apartment and is relatively near to the balcony doors where a heat gain relatively greater than the rest of the room may be experienced
The test can be considered to give a reflection of a slightly higher than normal saving for an occupied apartment. Assessment Calculations Compressor Optimisation So from the table of data the substitutions can be made within the following calculation ((original compressor run log events minus new compressor run log events) / original run events) x 1 to give the percentage change / improvement. For AM comparisons from the above table ((488-19)/488 x 1 = 59.4% improvement For PM comparisons from the above table ((55-192)/55) x 1 = 61.9% improvement For an overall comparison from the above table ((99-85)/99) x1 = 61.22% overall improvement in compressor operation. Assessment Calculations Utility Cost Saving Use of the above improvement figure can be made alongside a mean Ampere drawn value (obtained from the current data logger) to determine credible utility savings. A previously stated the current value seen on the data logger varied between 12. and 17 amps on a baseline of between.4 and.6, using these values produces a mean of ((17+14.65)/2) (.6+.4)/2) = 14.15 amps, if this is then applied to an average power factor of.89, ((14.15x24)x.89)/1 a working consumption of.22 kw is obtained. From the table values the A/C unit operated for 77.57% of the test time when AES was not operational so using this and the working consumption of.129kw as a benchmark means that a saving value can be directly obtained; 64 hours test duration with 77.57% A/C use (64/1) x 77.57 = 49.64 hours actual utility consumption, 49.64 hours x.22 kw= 15.1 kwhr consumed during ordinary non-aes consumption, if this normal operational value is multiplied by the AES improvement percentage a value can be obtained that quantifies the AES saving in utility, (15.1 /1) x 61.22 = 91.8 giving a saving of 91.8 kwhr for a comparable 64 hour period with AES operational. From the data it can be seen that the AES saves 18 1mins of compressor run time each operational hour.
Conclusion 1. The daily temperature graphs show that the conditioned room temperature is not adversely affected for comfort level whilst obtaining the imposed savings from the AES. 2. The weekly humidity graph shows that the conditioned room humidity is not adversely affected for comfort level whilst obtaining the imposed savings from the AES.. It can be stated that conditioned room comfort control is not compromised by the AES energy saving. 4. The large gain in savings as a headline number is pleasing but should in reality be mitigated slightly because of the vacant test room. 5. Installation of the AES has obvious running cost benefits to the future apartment occupants. The AES is proved to make excellent savings.