SEMINAR REPORT ON ENERGY AUDIT
SUBMITTED BY: AMANDEEP KAUR ROLL NO : PO/1002(100378080975) BRANCH : M.Tech(Power engg.)
SUBMITTED TO: Er.GAGANDEEP SINGH SODHI
INDEX OF CONTENTS Sr No. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Contents Introduction Energy Audit Model Types of Energy Audit Impacts of Energy Audit Instruments for Energy Audit Energy Audit for Electrical System Energy Audit for illumination System Home Energy Audit Specific Audit Technique Infrared Thermography Audit Pollution Audit Advantages of Energy Audit
INTRODUCTION An energy audit is an inspection, survey and analysis of energy flows for energy conservation in a building, process or system to reduce the amount of energy input into the system without negatively affecting the output(s). PRINCIPAL: When the object of study is an occupied building then reducing energy consumption while maintaining or improving human comfort, health and safety are of primary concern. Beyond simply identifying the sources of energy use, an energy audit seeks to prioritize the energy uses according to the greatest to least cost effective opportunities for energy savings. MAIN ISSUES: •
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The analysis of building and utility data, including study of the installed equipment and analysis of energy bills; The survey of the real operating conditions; The understanding of the building behaviour and of the interactions with weather, occupancy and operating schedules; The selection and the evaluation of energy conservation measures; The estimation of energy saving potential; The identification of customer concerns and needs.
ENERGYAUDIT MODEL DIAGRAM:
TYPES OF ENERGY AUDIT: 1.Benchmarking 2.Walk through audit 3.General energy audit 4.Investment grade audit The description of each type is as following: 1. Benchmarking: This first analysis consists in a preliminary Whole Building Energy Use (WBEU) analysis based on the analysis of the historic utility use and costs and the comparison of the performances of the buildings to those of similar buildings. This benchmarking of the studied installation allows determining if further analysis is required; Benchmarking mainly consists in comparing the measured con sumption with reference consumption of other similar buildings or generated by simulation tools to identify excessive or unacceptable running costs. As mentioned before, benchmarking is also necessary to identify buildings presenting interesting energy saving potential. An important issue in benchmarking is the use of performance indexes to characterize the building. These indexes can be: •
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Comfort indexes, comparing the actual comfort conditions to the comfort requirements; Energy indexes, consisting in energy demands divided by heated/conditioned area, allowing comparison with reference values of the indexes coming from regulation or similar buildings; Energy demands, directly compared to “reference” energy demands generated by means of simulation tools.
2. Walk-through audit: The preliminary audit (alternatively called a simple audit, screening audit or walk-through audit) is the simplest and quickest type of audit. It involves minimal interviews with site-operating personnel, a brief review of facility utility bills and other operating data, and a walk-through of the facility to become familiar with the building operation and to identify any glaring areas of energy waste or inefficiency. Preliminary analysis made to assess building energy efficiency to identify simple and low-cost improvements but also a list of energy conservation measures (ECMs, or energy
conservation opportunities, ECOs) to orient the future detailed audit. This inspection is based on visual verifications, study of installed equipment and operating data and detailed analysis of recorded energy consumption collected during the benchmarking phase; Advantages
1.This type of audit include faster results and lower cost. EMO's can be implement faster. 2.During the walk-through audit if the auditor uncovers EMO (Energy Management Opportunities) that could benfit from a comprehensive audit , the auditor may well recommend a more sophisticated audit for a specific part of a system or process. Disadvantages
Not as sophisticated as a comprehensive energy audit, less data collected and analysed
3.Detailed/General energy audit: The general audit (alternatively called a mini-audit, site energy audit or detailed energy audit or complete site energy audit) expands on the preliminary audit described above by collecting more detailed information about facility operation and by performing a more detailed evaluation of energy conservation measures. Utility bills are collected for a 12 to 36 month period to allow the auditor to evaluate the facility's energy/demand rate structures and energy usage profiles. If interval meter data is available, the detailed energy profiles that such data makes possible will typically be analyzed for signs of energy waste . Additional metering of specific energy-consuming systems is often performed to supplement utility data. In-depth interviews with facility operating personnel are conducted to provide a better understanding of major energy consuming systems and to gain insight into short and longer term energy consumption patterns. This type of audit will be able to identify all energy-conservation measures appropriate for the facility, given its operating parameters. A detailed financial analysis is performed for each measure based on detailed implementation cost estimates, sitespecific operating cost savings, and the customer's investment criteria. Sufficient detail is provided to justify project implementation.
Based on the results of the pre-audit, this type of energy audit consists in energy use survey in order to provide a comprehensive analysis of the studied installation, a more detailed analysis of the facility, a breakdown of the energy use and a first quantitative evaluation of the ECOs/ECMs selected to correct the defects or improve the existing installation. This level of analysis can involve advanced on-site measurements and sophisticated computer based simulation tools to evaluate p recisely the selected energy retrofits;
Advantages
The standard energy audit is more detailed than the walk-through audit, more data is collected and analysed. Being more through less likely to overlook more complex EMO's Disadvantages
The standard energy audit takes the auditor more time, data loggers are used to collect additional data - therefore the is more expensive than the walk through audit. Often time consuming data collection is far to too exhaustive to add value. 4. Investment-Grade audit: In most corporate settings, upgrades to a facility's energy infrastructure must compete for capital funding with non-energy-related investments. Both energy and non-energy investments are rated on a single set of financial criteria that generally stress the expected return o investment (ROI). The projected operating savings from the implementation of energy projects must be deve loped such that they provide a high level of confidence. In fact, investors often demand guaranteed savings. The investment-grade audit expands on the detailed audit described above and relies on a complete engineering study in order to detail technical and economical issues necessary to justify the investment related to the transformations. Advantages A very comprehensive energy assessment of the facility and its energy footprint, no stone
is left unturned in the search for EMO's (Energy Management Opportunites). Suitable for capital intensive investment programmes. Disadvantages
Very detailed, but time consuming. The detailed energy modelling and analysis requires many manhours. Time to market opportunities may be lost.
IMPACTS OF ENERGY AUDIT: 1.Production capacity 2. Quality of finished goods 3.Operational reliability 4. Maintenance requirement 5.Pollution environment 6.Plant safety 7.Industrial relations
INSTRUMENTS FOR ENERGY AUDIT: An energy audit requires a large number of measurements of various electrical and mechanical quantities. So these are as following: 1.Electrical Measurements and instruments a)Voltmeter and ammeter to measure voltage and current b)Power factor to measure power factor c)Synergy meter : This instrument measures and record current, voltage, power factor, frequency. 2.Lightining Measurement: Usually lux meter is very convenient instrument to measure the level of illumination. 3.Chemical Measurements: a)Dragger: It indicates the degree of combustion in a boiler the extent of carbonmonoxide in the flue gases. b)Fyrite Kit: This kit is used to measure percentage of carbondioxide and oxygen in the flue gases. 4.Humidity measurements: The instruments used for this are dew point hygrometer, electrical conductivity humidity meter, electrolytic hygrometer. 5.Temperature Measurements: a)Glass stem thermometer: Mercury in glass, alcohol in glass. They are used for temperature measurement of gas,air and liquids in the range of 20 to 500 deg c. b)Optical Pyrometer c)Radiation pyrometer:This is very accurate but costly. It is suitable for high temperature.
ENERGY AUDIT OF ELECTRICAL SYSTEM: Every plant uses a number of electrical motors as drives. The full load efficiency of a 3 phase induction motor varies from 80% to 90% depending on size.
It is adviseble to replace the existing low efficiency low power factor by high efficiency high power factor motors.The payback period of such a conversion is only a couple of years due to high cost of motor is an important asprct of energy management programme. Thus the method available to reduce electrical energy costs include:
1.Improvement of power factor 2.Selection of motors of proper size 3.Replacement of existing motors by energy efficient motors.
ENERGY AUDIT OF MECHANICAL SYSTEM: It includes: 1.Fans and blowers 2.Compressed air system 3.Air conditioning and refrigeration system 4.Exhaust and ventilation system
ENERGY AUDIT OF COMPRESSED AIR SYSTEM:For this we take following steps: 1.Air filter 2. inter cooler 3.Moisture separator 4.Air receiver Compressed air is required in a number of industries like iron and steel, cement, chemical process etc. It consist of two compressor alongwith air filters, cooling water system, lubrication system. Between the stages intercooler is provided. Its function is to cool the air to reduce its volume and also to condense the moisture in air. The moisture separator also seperates the remaining moisture from the compressed air. The air receiver is the Storage system for compresses air.The distribution system for the compressed air consist of valves, piping, pressure,regulators etc.
ENERGY AUDIT OF ILLUMINATION SYSTEM: Every plant has an extensive illumination system. The electric energy used for illumination is a significant portion of total electrical energy requirements especially in case of plants having night shifts. Total lumen requirement= EXA/CXM Where
E = illumination level A = area to be illuminated C = coefficient of utilization M = maintenance factor
DIFFERENT WAYS FOR ILLUMINATION:
HOME ENERGY AUDIT:
A home energy audit is a service where the energy efficiency of a house is evaluated by a person using professional equipment (such as blower doo rs and infra-red cameras), with the aim to suggest the best ways to improve energy efficiency in heating and cooling the house. An energy audit of a home may involve recording various characteristics of the building envelope including the walls, ceilings, floors, doors, windows, and skylights. For each of these components the area and resistance to heat flow (R-value) is measured or estimated. The leakage rate or infiltration of air through the building envelope is of concern, both of which are strongly affected by window construction and quality of door seals such as weatherstripping. A home energy audit may include a written report estimating energy use given local climate criteria, thermostat settings, roof overhang, and solar orientation. This could show energy use for a given time period, say a year, and the impact of any suggested improvements per year. In the United States
In the United States, this kind of service can often be facilitated by: • •
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Public utility companies, or their energy conservation department. Independent, private-sector companies such as energy services company, insulation contractor, or air sealing specialist. (US) State energy office.
In Lebanon
Since 2002, The Lebanese Center for Energy Conservation (LCEC) initiated a nationwide program on energy audits for medium and large consuming facilities. By the end of 2008, LCEC has financed and supervised more than 100 audits. LCEC launched an energy audit program to assist Lebanese energy consuming tertiary and public buildings and industrial plants in the management of their energy through this program.
BENEFITS OF HOME ENERGY AUDIT: 1.Save Money on Your Energy Bills
A RESNET Certified home energy professional is trained to pinpoint the areas of your home where energy is being wasted and used inefficiently. More importantly, the report will prioritize cost-effective improvement opportunities that will pay financial dividends every time your utility bill arrives. 2.Increase Your Comfort
When you implement home improvements recommended by a RESNET Certified professional, you will literally feel the difference. Air sealing the building shell, sealing leaky air handler ducts, adding insulation, or replacing that old furnace or air conditioner will make your home a more pleasant place to be. 3.Increase Your Home's Resale Value
For every $1 decrease in annual energy costs, the market value of a home increases by $20, according to a study published in the Appraisal Journal. If you decrease your ene rgy costs by $300 per year, the value of your home increases by $6,000. RESNET Certified professionals can verify measurable results of the improvements performed. 4.Improve Your Home's Marketability
With rising fuel costs, home buyers are seriously considering the house's operating expenses. Measures to lower utility bills are valuable home improvements that reap dividends month after month. A home buyer will also have confidence that the house has been optimally maintained when you show it was audited by a RESNET Certified professional and retrofitted by a RESNET Qualified EnergySmart Contractor. You're more likely to make a faster sale for a higher price
SPECIFIC AUDIT TECHNIQUE:
a) INFRARED THERMOGRAPHY AUDIT The advent of high resolution thermography has enabled inspectors to identify potential issues within the building envelope by taking a thermal image of the various surfaces of a building. For purposes of an energy audit, the thermographer will analyze the patterns within the surface temperatures to identify heat transfer through convection, radiation, or conduction. It is important to note that the thermography ONLY identifies SURFACE temperatures, and analysis must be applied to determine the reasons for the patterns within the surface temperatures. Thermal analysis of a home g enerally costs between 300 and 600 dollars. For those who cannot afford a thermal inspection, it is possible to get a general feel for the heat loss with a non contact infrared thermometer and several sheets of reflective insulation. The method involves measuring the temperatures on the inside surfaces of several exterior walls to establish baseline temperatures. b)POLLUTION AUDIT:
With increases in carbon dioxide emissions or other greenhou se gases, pollution audits are now a prominent factor in most energy audits. Implementing energy efficient technologies help prevent utility generated pollution.Online pollution and emission calculators help approximate the emissions of other prominent air pollutants in addition to carbon dioxide. Pollution audits generally take electricity and heating fuel c onsumption numbers over a two year period and provide approximations for carbon dioxide, VOCs, nitrous oxides, carbon monoxide, sulfur dioxide, mercury, cadmium, lead, mercury compounds, cadmium compounds and lead compounds.
ADVANTAGES OF ENERGY AUDIT:
When an energy audit is conducted on your home, a professional assess the property to determine how energy-efficient your structure is overall. This kind of audit is a good way to find out where excess energy may be creeping out of your home. It also shows you where elements of your home that are not energy-efficient may contribute to the problem. This is important because lost energy often results in higher utility bills, which can be a financial strain on you as the homeowner.
1.Increased Comfort: Because an energy audit reveals virtual cracks in your home's ability to distribute energy -- including heated and cooled air from heating, ventilation and air conditioning (HVAC) systems -- you can address those issues effectively. Solutions include sealing the space around doors and windows and figuring out how to better insulate your home. The result is a cooler-feeling home during the summer months and a warmer home during the winter months. 2, Cost Savings: Because you are no longer heating or cooling the entire outdoor area of your home, you can save money on your electric bill. When the air is contained in the space in which it was mean to distribute heated or cooled air, your system has to work less. This, in turn, means that with less electrical output from your system, you pay less each month in utilities. In fact, according to the Energy Audits Unlimited website, you can save between 20 and 30 percent on the cost to heat or cool your home. 3. Environmental Impact: An energy audit can provide satisfaction for those people interested in conserving energy for the sake of the environment. Being more energy efficient means that your home has less of a negative environmental impact on the environment around you. An energy audit also means that you contribute less to global warming because your unit is being more efficient and releasing fewer carcinogens and other harmful emissions into the air. 4. Improved Resale Value: Your home resale value is greatly improved with a professional energy audit. The renovations that you make to improve energy efficiency will increase the value of your home. In fact, home improvements for the sake of energy efficiency are the only home improvements that actually pay for themselves in the long run.
REFERNCES: 1. Chen Zhongping The analysis of energy consumption and energy-saving potential in existing publich builidngs[J]. Journal of Wuhan polytechnic university 2008,27(3): 93-95. 2. Zhou Liping, Liu Zhixin Cao Jinan. Reseach on building energy consumption audit and energy-saving measures for a hospital in shanghai[J].Jouranl of industrial construction 2008(38):9-11. 3. Zhen Shuping, Deng lin Chen Guijun Energy audit methodology[J]. Shanghai Energy 2008(4): 37-39. 4. Lou Chengzhi, Yang Hongxing etc Energy audit of buildings: a case study of a commercial building in causeway bay of HongKang [J]. Joural of HV&AC ,2006(36) :44-50. 5. ASHRAE Energy Managemen[G] ASHRAE Applications Handbook 1999.others 28.2% elevator 21.2% lighting 7.5% air-conditioning 43.1% 6. Generation of electrical Energy by B.R.Gupta
