Energy Audit A case study

Transcription

1 Energy Audit A case study R. Hari Baskar 1, Hitu Mittal 2, Mahesh S Narkhede 3, Dr. S.Chatterji 4 1Lecturer, Directorate of Training and Technical Education, Government of Delhi 2Assistant Professor, Lord Krishna College of Engineering, Ghaziabad, Uttar Pradesh 3Research Scholar, Electrical Engineering Department, NITTTR, Chandigarh 4Professor and Head, Electrical Engineering Department, NITTTR, Chandigarh Abstract Educational Institutions are often overlooked as a contributor to energy intensive operations in India within the commercial buildings sector. An energy cost is one of the manageable costs within an institute s budget and can be managed effectively. Resultant cost and energy savings will go a long way in reducing energy use within the sector and provides a venue for reinvestment within the educational institute itself. An energy study review of various international and national educational institutions indicates that 5-20% of energy can be saved. This paper / audit report is aimed at Managing Energy use in National Institute of Technical Teachers Training and Research-Hostels (NITTTR), Chandigarh. It is a concerted attempt in achieving improved energy performances. This study aims to highlight several opportunities to create and implement an energy management plan within NITTTR, Chandigarh. The audit was conducted and suitable strategies of adjusting and optimizing energy were suggested so as to reduce energy requirements and hence, the total cost spent towards energy consumption. Keywords Energy Audit, Educational Sector, Pay Back period, Light Loads I. INTRODUCTION A nation is fully advanced in proportion to the spread of education among the common people and development of their intelligence. In India the entire field of education and other fields of intelligent activities had been monopolized by a handful of men before independence. But today we are marching towards the desirable status of a developed nation with fast strides. But the development should be a sustained one. For achieving such a interminable development energy management is essential. The present electricity consumption in the commercial buildings sector in India is about 8-10% of the total electricity. The electricity demand in commercial buildings is growing annually by 11-12% due to demands for providing international level comforts and facilities. This presents a challenge to ensure that energy growth in commercial building does not become unmanageable, but at the same time, also presents an opportunity to influence and address energy management issues in various commercial buildings and facilities. In any industry, the three top operating expenses are often found to be energy (both electrical and thermal), materials and labour. Amongst all these if we think of cost or potential cost savings then energy would invariably emerge as a top ranker. Hence, energy management function constitutes a strategic area for cost reduction. The energy audit was conducted at the hostels of National Institute of Technical Teachers Training & Research, Chandigarh, to identify the major areas of energy waste. The energy audit was conducted within a span of three days. II. AUDIT PHASE The energy audit is a wide spectrum of energy study which ranges from identifying major energy problem areas to implications of alternative energy efficient measures. It involves analyzing the actual consumption of electrical energy and measures of energy conservation. Energy Audit helps to understand more about the ways energy and fuel are used in any industry and help in identifying the areas where waste can occur and where scope for improvement exists. Initially a walk though audit was conducted. The rooms at all the three Men s hostels & one women s Hostel were investigated. The connected load and its wattage were noted. During such visit macro information like number of hours of actual usage of fluorescent light, fan, power points etc. was collected. Some of the electrical load points were photographed. The main objective was to explore the major energy problem. It was found that there was a scope for conduct of a General audit. The general audit was conducted by measurement of actual energy consumption, duration, power factor on number of light wired loads. The illumination level was measured. The size of the rooms and the electrical fittings in it like light, fan and ventilation were noted. The measurement was conducted both inside the rooms and in common places like verandahs, bathrooms, toilets etc. The energy consumption pattern is shown in Fig.1 Lord Krishna College of Engineering (An ISO 9001:2008 Certified Institute) Ghaziabad, Uttar Pradesh, INDIA. Page 73

2 Hence, it was suggested that 40 watt fluorescent lamp may be replaced with 29 Watt CFL. The Comparison of existing energy consumption with recommended consumption in case of fluorescent lamp is shown in Fig.2 Flourescent Light Fig.1 Energy consumption pattern It was observed that if the energy efficient measures are suggested in three categories Viz., Lighting, Ventilation & heating / cooling, it will fetch a fruitful result. Accordingly, in depth analysis of these three categories were carried out. The outcome / suggestions are listed below: Recommended Energy Saving Measures Audit Para (i): Fluorescent Lamp Replace the 40 watt Lamp with 29 Watt lamp :- a)wattage of Existing Lamp = 40 w Duration of use / year / lamp days = 8Hrs. X 365 = 2920 Total Number of lamps = 422 Total energy consumption ( 40 X 2920 X 422 ) = Kw Wattage of CFL (proposed) = 29 w The difference in energy consumption= 11 w Total energy consumption with replacement = Kw The difference in energy consumption = Kw Saving, i.e difference in energy bill: Cost / Rs.5/- (1 unit = 1 KWh) Saving ( KW X 5 ) =Rs /- b) Cost of 40W with depreciation factor of 50 % = 30 x 422 = Rs /- Cost of Installation of 29 W of Lamp =Rs.100x422 =Rs.42200/- The additional expense to the exchequer (Rs Rs.12660) = Rs /- c) Pay Back Period ( 29540/ ) = years Audit Observation :Life of CFL is approx 3 to 4 years. The additional cost incurred towards the replacement will be paid back in 4 to 5 months time period % % Total Energy Consumption of equipment / year (kwh) Total Energy Consumption after replacement / year (kwh) Fig.2 Comparison of existing and recommended energy consumption in case of fluorescent lamp Audit Para (ii): Fan (ceiling) Replace the 60 watt fans with 50 watt good quality Havells / Khaitan fans :- a)wattage of Existing Fan = 60 w Duration of use / year / fan = 18 Hrs. X 245 days = 4410 Hrs. Total Number of fans = 589 Total energy consumption (60 X 4410 X 589) = Kw Wattage of fan (proposed) = 50 w The difference in energy consumption= 10 w Total energy consumption with replacement = Kw The difference in energy consumption = Kw Saving, i.e difference in energy bill: Cost/Unit@ Rs.5/-(1 unit = 1 KWh) Saving ( Kw X 5 ) = Rs /- b) Cost of 60 W Fan with depreciation factor of 50 % = 700 x 589 = Rs.4,12,300/- Cost of Installation of new Fan of 50 W = Rs x 589 = Rs.9,42,400/- The additional expense to the exchequer (Rs.9,42,400- Rs.4,12,300) = Rs. 5,30,100/- Lord Krishna College of Engineering (An ISO 9001:2008 Certified Institute) Ghaziabad, Uttar Pradesh, INDIA. Page 74

3 c) Pay Back Period ( 5,30,100 / 1,29,874.5) = 4.08 years Audit Observation: The additional cost incurred towards the replacement will be paid back in 4 to 5 years time period. Life of fans is approx 10 to 15 years. Hence, the audit party suggested for replacement. The Comparison of existing energy consumption with recommended consumption in case of fan is shown in Fig.3 Audit Observation: The additional cost incurred towards the replacement will be paid back in 2 to3 months time period. Life of CFL is approx 4 to 5 years. Hence, it was suggested for replacement. The Comparison of existing energy consumption with recommended consumption in case of night lamp is shown in Fig.4 Night Lamp Fan (Ceiling) % % Total Energy Consumption of equipment / year (kwh) % % Total Energy Consumption of equipment / year (kwh) Total Energy Consumption after replacement / year (kwh) Total Energy Consumption after replacement / year (kwh) Fig.3 Comparison of existing and recommended energy consumption in case of fan Audit Para (iii): Night Lamp If we replace the 14 watt CFL with 5 watt CFL. :- a)wattage of Existing Night Lamp = 14 w Energy consumption in 14 W CFL for a year = 0.014x240x2190 = kwh Cost / Rs.5/- (1 unit = 1 KWh) (7358.4KWh x Rs. 5.00) = Rs.36,792/- Energy consumption in 5 W CFL for a year = 0.05 x 240 x 2190 = 2628 kwh Cost / Rs ( 2628 kwh x Rs. 5.00) = Rs.13,140/- Saving, i.e difference in energy bill (Rs Rs.13,140/-) = Rs. 23,652/- b) Cost of 14 W CFL with depreciation factor of 50 % = 100 x 240 = Rs.24000/- Cost of Installation of 5 W of CFL = Rs. 80 x 240 = Rs.19,200/- The additional expense to the exchequer ( Rs Rs.19200) = Rs. 4800/- c) Pay Back Period = 4800 / = years Fig.4 Comparison of existing and recommended energy consumption in case of night lamp The energy consumption pattern in case of each load, energy conservation after implementation of energy saving measures were suggested in energy audit and subsequent pay-back period is calculated. Estimated Energy Saving is found to be KWh. The total Saving to Govt. exchequer per annum is estimated to be Rs. 2,45,707 /- A consolidated Table showing the energy consumption pattern before and after recommended energy saving measures and total energy conservation is depicted in Annexure I The energy production (supply) and consumption (demand) pattern at local and global level not only determines whether a country is developed or developing, it also bears some major issues like cost, pollution / carbon emissions, desertification etc. The major reasons for raise of demand in energy from the consumer point of view (demand side) are rapid raise in population, luxurious style of living, improper use of electrical equipment, inadequate knowledge etc. Hence, demand of energy is growing in a rapid phase but the supply or production is maintaining its own phase, resulting in a wide gap between demand and supply. The following measures were identified and are to be implemented in various phases. 1. Maximum utilization of natural light. 2. Combination of natural and artificial light. 3. Sensors to detect natural lighting and switch on artificial light. Lord Krishna College of Engineering (An ISO 9001:2008 Certified Institute) Ghaziabad, Uttar Pradesh, INDIA. Page 75

4 4. Electrical door locks in each room. In such type of locks the supply will be disconnected as soon as key is removed (from the switch board), in that particular room. The master switch to be installed which operates if the keys are inserted in it after entering the room. 5. It is recommended the chokes in Old hostel with electronic ballast can be installed which will reduce connected load by W for each load point. 6. Bathroom lights: a. CFL of 10W can be used instead of 40 W Fluorescent tube (40 W) in bathrooms. b. In new hostels number of light points in bathrooms and toilets can be reduced to 60 %. Maintenance: 1. It is observed that the solar panels installed at the roof of new hostels are not being cleaned regularly. The surface panel needs to be cleaned in regular intervals so that efficiency can be increased to the maximum extent. 2. It is observed several joints / nodes in wiring. It is recommended that such conductors are to be replaced. 3. Replacing conventional electrical regulators in old hostel to electronic type regulators for controlling the speed of ceiling fans. Acknowledgment The authors would like to express heartfelt gratitude to Dr. M.P.Punia, Director, NITTTR for providing this opportunity in conducting the audit. III. CONCLUSION In present scenario the energy conservation plays an important role. It is because consumption of energy is increasing day by day and the generation is not matching with it. The energy conservation helps in reducing the energy consumption and provide the savings. By adopting proper measures as suggested in the report, i.e de-lamping, replacements etc., energy awareness to make the people aware the importance of energy the required result can be achieved. It is also reported that the audit was aimed at conservation of energy in Hostels only. If energy audit for the entire institute is conducted, which includes laboratories, workshop, Staff room, office etc the quantitative energy conservation will be more. REFERENCES [1] Nissanga Nishad Mendis, Nisal Perera Energy Audit: A Case Study, Proceedings of International Conference on Information and Automation (ICIA 2006),Shandong,China,pp.45-50,15-17 December 2006 [2] Harapajan Singh, Manjeevan Seera,Mohamad Adha Mohamad Idin- Electrical Energy Audit in a Malaysian University- A case Study, Proceedings of International Conference on Power and Energy (PECon),Kota Kinabalu Sabah, Malasia,pp ,2-5 December [3] Muhammad Usman Khalid, Mariam Gul, Mohammad Mohsin Aman. Ahsan Hashmi- Energy Conservation through Lighting Audit, Proceedings of International Conference on Power and Energy (PECon),Kota Kinabalu Sabah, Malasia, pp , 2-5 December 2012 [4] Xin Wang and Chen Huang, Wuwei Cao- Energy Audit of Building: a case study of A Commercial Building in Shanghai, Proceedings of Asia Pacific Power & Energy Engineering Conference, Chengdu, China, pp 1-4, March [5] Bureau of Energy Efficiency, Ministry of Power, Government of India, Hand Book on Energy Efficiency Lord Krishna College of Engineering (An ISO 9001:2008 Certified Institute) Ghaziabad, Uttar Pradesh, INDIA. Page 76

5 Name of Equipment Flourescent Lamp "Sharpening Skills... Annexure I Consolidated Table showing the energy consumption pattern before and after recommended energy saving measures and total energy conservation. Power Rating (Watt) Number of Equipment Total load of equipment (Watt) P.F Usage/ Year (in Hours) Total energy consumption of equipment/ year (Kwh) Total Energy Consumption After Replacement X365= Night Lamp X365= Energy Saving (kwh) Fan X245= Fan Passage X365= Corridor Light X365= (60%) Over lapping of luminous flux Water geysers X180= Leakage of water ; no proper Water cooler 600/ 755/ 1550 Fountain Motor 4/8/ X200= Use of water from cooler for hand washing observed during audit visit. Needs X365= wastage of energy Refrigerator X365= Needs to be switched off during half winter / winter season Roaster / Chappati maker X365= Skilled cook needs to operate Lift X365= Operator / personnel may be appointed 4526 To be reduced to 60 % 1800 Kwh can be saved, if properly maintained. Place warning stickers, signage, indicating only for drinking purpose. 10 % wastage Kwh Motors can be used for gardening purpose. 650 Kwh Nil No Lord Krishna College of Engineering (An ISO 9001:2008 Certified Institute) Ghaziabad, Uttar Pradesh, INDIA. Page 77

6 Exhaust Fan X365= Actual usage time is too high Saving to Government exchequer X = Rs. 2,45,707 /-; The Actual energy consumption= KWh; Estimated Energy Saving = KWh (Pertains to energy saving in respect of hostel buildings only ) Lord Krishna College of Engineering (An ISO 9001:2008 Certified Institute) Ghaziabad, Uttar Pradesh, INDIA. Page 78