KNUST Technical Courses on Energy Efficiency PDF

Kwame Nkrumah University of Science & Technology, Kumasi, Ghana Technical courses on energy efficiency – Saving potentials Gina Ditzen Consultant Arqum GmbH 1 Energy Efficiency - Saving Opportunities Com...

Kwame Nkrumah University of Science & Technology, Kumasi, Ghana Technical courses on energy efficiency – Saving potentials Gina Ditzen Consultant Arqum GmbH 1 Energy Efficiency - Saving Opportunities Compressed Heat & Motors, IT & Behavior Lighting Drives & & Air Cooling Pumps vehicles Motivation www.knust.edu.gh www.knust.edu.gh 2 Compressed Air …one of the most expensive forms of energy Used for: Cleaning workpieces Power tools such as air hammers, drills, wrenches Enabling cooling Painting and varnishing …. www.knust.edu.gh www.knust.edu.gh 3 Compressed Air …one of the most expensive forms of energy Reasons for energy losses: Leakages Pressure losses Lack of or improperly fine-tuned compressor control Immature maintenance concepts Failure to utilize waste heat www.knust.edu.gh www.knust.edu.gh 4 Compressed Air Potential savings First: Is compressed air needed for the process? Is there an alternative? Second: Identify inefficiencies Exchange inefficient parts of the compressed air system Maintain the systems efficiency www.knust.edu.gh www.knust.edu.gh 5 Compressed Air Applications Do I need compressed air for my processes? Questions to start with: "Is compressed air actually needed for the process?" "Are there more efficient processes, e.g. for cleaning, cooling and drying? "Does the compressed air application/supply correspond to the utilization requirement? Targets: Substitute the use of compressed air as far as possible (if economical) - the savings potential is estimated at approx. 26 %. Practical tip: Systematically record where compressed air is used for which processes – this does not only give an overview of potential areas for energy savings but can also act as a guidance to help select alterative technologies. www.knust.edu.gh www.knust.edu.gh 6 Substitution Example I – Comparison of an air motor Examine the possibility of substitution: A comparison: A 6,3 kW air motor consumes as much energy as 20 electric motors á 6,5 kW The air motor requires a 132 kW compressor x20 www.knust.edu.gh www.knust.edu.gh 7 Substitution Example II – Comparison of an air orbital sander An example of substitution: Replacement of an air-powered random orbital sander with an electrically powered counterpart. Use: 2 hrs/day on 250 days/a, electricity work price: 0.15 GHS/kWh Compressed air Electric (7,5 bar) Electrical power 310 W 390 l/min consumption/ air consumption at the tool Compressor clamping 3.3 kW power Actual annual energy 155 kWh/a 2,650 kWh/a consumption Consumption-related costs 23.25 GHS/a 397.5 GHS/a www.knust.edu.gh Energy consumption factor 1 17 www.knust.edu.gh 8 Compressed air Updating the system can yield high efficiency improvements Outdated inefficient system New efficient system www.knust.edu.gh www.knust.edu.gh 9 Compressed air Reduction of pressure losses and leakages Reduction of pressure losses by shortening connections and preventing or closing leaks at connectors. Find leakages by listening, feeling and using leakage detectors. www.knust.edu.gh www.knust.edu.gh 10 Saving Opportunities – Compressed Air Efficiency of measures to improve energy efficiency 1. Optimization of pressure 2. Implementation of a master control 3. Implementation of an automatic switch off 4. Detachment of consumers 5. Implementation of a level controlled condensate drain 6. Detection of Leakages 7. Replacement of the filter 8. Implementation of heat recovery 9. Implementation of a frequency converter 10. Pressure reducing valve www.knust.edu.gh www.knust.edu.gh 11  Energy Efficiency - Saving Opportunities Heat & Motors, IT & Behavior Compressed Air Lighting Drives & & Cooling Pumps vehicles Motivation www.knust.edu.gh www.knust.edu.gh 12 Saving Opportunities – Lighting What can be done to reduce energy consumption for lighting? www.knust.edu.gh www.knust.edu.gh 13 Identifying optimization potential Check necessity of artificial lighting www.knust.edu.gh www.knust.edu.gh 14  Lighting Usage of natural light sources Usage of daylight in hall / work room Retrofitting reflectors Ceiling and wall cover color www.knust.edu.gh www.knust.edu.gh 15 Lighting Can be as simple as using natural day light Saved artificial light under Effects of the renovation/cleaning of renovated roof light panel the roof of a warehouse www.knust.edu.gh www.knust.edu.gh 16 Identifying optimization potential Regularly check state of lighting infrastructure Failing lighting system, risk of injury from falling lamps www.knust.edu.gh www.knust.edu.gh 17 Identifying optimization potential Check less used areas for state of lighting infrastructure Urgent need for action: "glowing" fluorescent lamps have a up to 4x higher power consumption www.knust.edu.gh www.knust.edu.gh 18 Identifying optimization potential Energy use for lighting can be reduced through separate workplace lighting Separate workplace lighting: General room lighting can be lowered Employees is responsible for “her/his” light www.knust.edu.gh www.knust.edu.gh 19 Lighting Technical light optimization Time switch Movement detectors Light control depending on daylight Dimmable light control Separate and individual light control LEDs www.knust.edu.gh www.knust.edu.gh 20 Lighting Calculation example Electricity costs of the current lighting 176 units Number of lamps Calculation of electricity consumption per year 18 W Power per lamp 176 units * 18 W * 100% * 10 h * 220 days = 6,969,600 W per year Capacity per lamp 100% = 6,969,60 kWh = 6,970 kWh 10 h Burning time per day 220 days Burning time per years Electricity cost per year 0.9 GHS Electricity cost per kWh 6,969,60 * 0,9 GHS/kWh = 6,272.64 GHS Electricity costs after conversion to LED 176 units Number of lamps Calculation of electricity consumption per year 7.5 W Power per lamp 176 units * 7.5 W * 100% * 10 h * 220 days = 2,904,000 W per year Capacity per lamp 100% = 2,904 kWh 10 h Burning time per day Electricity cost per year 220 days Burning time per years 2.904 * 0,9 GHS/kWh = 2,613.6 GHS 0.9 GHS Electricity cost per kWh Consumption saving per year: 4,066 kWh Electricity cost savings per year: 3,659.04 GHS www.knust.edu.gh www.knust.edu.gh 21  Energy Efficiency - Saving Opportunities Heat & Motors, IT & Behavior Compressed Air Lighting Drives & & Cooling Pumps vehicles Motivation www.knust.edu.gh www.knust.edu.gh 22 Industrial heat processes High share of energy consumption 64 % of total industrial 36% energy consumption Efficiency potential: 30 % 64% Process heat remaining consumption www.knust.edu.gh www.knust.edu.gh 23 Types of industrial heat processes Drying, melting and forging processes Drying processes: High capacity for water absorption Suitable for efficient and fast drying of materials Moisture is removed from the material by convection Melting and forging processes: Large thermal energy demand in the metallurgical industry For example, blast furnaces for steel production www.knust.edu.gh www.knust.edu.gh 24 Types of industrial heat processes Steam processes Steam processes → in the form of steam Example: Steam turbine, which uses steam at a high temperature and pressure level to produce electrical energy www.knust.edu.gh www.knust.edu.gh 25 Heat Avoiding unnecessary energy consumption Analysis of energy consumption and processes Evaluation into avoidable or unavoidable waste heat www.knust.edu.gh www.knust.edu.gh 26 Heat - avoiding unnecessary energy consumption Waste heat - Principle: First avoid or reduce, then use! Starting points for avoidable waste heat: Dimensioning Control Temperature level Insulation www.knust.edu.gh www.knust.edu.gh 27 Heat - avoiding unnecessary energy consumption Specific optimization options Dimensioning of boilers Multi-boiler control Condensing boilers Controllable burners … www.knust.edu.gh www.knust.edu.gh 28 Heat - avoiding unnecessary energy consumption Optimal insulation / isolation Goal: Reduce the energy loss that occurs due to the temperature difference between the process medium and the environment. Reduction of heat losses by up to 30 % possible Heat that does not have to be produced in the first place has the best greenhouse gas balance! www.knust.edu.gh www.knust.edu.gh 29 Process Heat Evaluate heat loss and recovery options Pipe insulation Leakage avoidance Close waste heat sinks Recover waste heat Boiler efficiency www.knust.edu.gh www.knust.edu.gh 30 Process heat generation Heat recovery www.knust.edu.gh www.knust.edu.gh 31 Heat - Efficient use of energy in existing plants Waste heat utilisation technologies Direct integration of waste heat into processes and plants​ Integration of waste heat into other operating processes​ Disclosure to third parties​ Conversion of waste heat into other forms of useful energy www.knust.edu.gh www.knust.edu.gh 32 Heat - Efficient use of energy in existing plants Waste heat utilisation technologies www.knust.edu.gh www.knust.edu.gh 33 Cooling Maintenance ensures efficiency Check the tightness of the refrigeration circuit regularly Check the insulation of the pipes regularly Regular cleaning of the capacitors Checking of temperature level and plant operating time www.knust.edu.gh www.knust.edu.gh 34 Saving Opportunities – Air conditioning What can be done to reduce energy consumption for air conditioning? www.knust.edu.gh www.knust.edu.gh 35 Air Conditioning Behavior has large potential for cost savings Consumer behaviour Distribution of air flows Storage of cooling fluid Generation of air flows www.knust.edu.gh www.knust.edu.gh 36 Air Conditioning Easy measures can quickly improve efficiency Correct selection and regular maintenance of air filters Avoidance of pressure losses due to pipe friction or individual resistances (heating coil, silencer, filter) Adjustment of operating hours to actual use Volume flow adapted to demand? (Office: 30 m³/h air per person) Adaptation of fan speed to demand www.knust.edu.gh www.knust.edu.gh 37  Saving opportunities – Air-conditioning Improvement measures address system design and settings Water / groundwater Insulation of pipes Optimal placement of / night cooling the air inlets or air systems outlets Detect leakages Reduction of the System System operating time design settings Reduce internal loads (deduction of waste heat from machines) Adaption of the air Reduce external volume flow and loads (sunblind, temperature to the real Use heat recovery need thermal insulation) www.knust.edu.gh www.knust.edu.gh 38 Saving opportunities – Ventilation There is a high number of potential saving 1. Minimizing the need for ventilation 2. Adjustment of control 3. Use of Heat recovery 4. Installation of Sensors 5. Use of a frequency converter 6. Detection of Leakages 7. Replacement of the fan 8. Replacement of the motor 9. Replacement of the belt 10. Replacement of filters www.knust.edu.gh www.knust.edu.gh 39  Energy Efficiency - Saving Opportunities Heat & Motors, IT & Behavior Compressed Air Lighting Drives & & Cooling Pumps vehicles Motivation www.knust.edu.gh www.knust.edu.gh 40 Electric Motors Facts and Figures Electric motors consume 43-45% of the worlds electric energy consumption A standard industrial company uses 70% of their total electricity consumption on electric motors www.knust.edu.gh www.knust.edu.gh 41 Motors, Drives & Pumps Optimization potential and measures Use of highly Speed Control Avoidance of Use efficient efficient and frequency oversizing gears motors converter Old motors Adjustment Reduction