TABLE OF CONTENTS TOC o “1-8” u CHAPTER 4 PAGEREF _Toc509414307 h 1 RESULT AND DISCUSSION PAGEREF _Toc509414308 h 1 4
TABLE OF CONTENTS
TOC o “1-8” u CHAPTER 4 PAGEREF _Toc509414307 h 1
RESULT AND DISCUSSION PAGEREF _Toc509414308 h 1
4.1Introduction PAGEREF _Toc509414309 h 1
4.2Estimated Output Power Generated by Micro Hydro Generator PAGEREF _Toc509414310 h 1
4.3Return on Investment (ROI) PAGEREF _Toc509414311 h 7
4.4Contribution of the Operation of Micro Hydro Generator on Pumping System of Aeration Tank in the Sewerage Treatment Plant PAGEREF _Toc509414312 h 11
4.5Practicality of Speculative Micro Hydropower Situations PAGEREF _Toc509414313 h 12
4.6Micro Hydro Generator Available in Reality between Head and Power Output PAGEREF _Toc509414314 h 13
CHAPTER 5 PAGEREF _Toc509414315 h 16
CONCLUSION PAGEREF _Toc509414316 h 16
5.1Summary PAGEREF _Toc509414317 h 16
5.2Recommendation PAGEREF _Toc509414318 h 17
5.3Innovation and Commercialization PAGEREF _Toc509414319 h 18
REFERENCES PAGEREF _Toc509414320 h 19
CHAPTER 4RESULT AND DISCUSSION4.1IntroductionThis chapter will discuss all the results that obtained from the calculation of output power generated by micro hydro generator embedded at 100,000 PE of the Juru Sewerage Treatment Plant and also the ROI/payback period is summarized under consideration of the actual application of micro hydro generator in Juru Sewerage Treatment Plant.
4.2Estimated Output Power Generated by Micro Hydro GeneratorThe electrical power can be generated from the turbine at Juru STP was determined based on the head, flow, and constants related to the water density, gravitational acceleration, and efficiency by using Equation 3.0.
Pe=Ph×?=Q×H×g×?×?Where, Pe is electrical power (kW)
Ph is hydraulic power (kW)
? is the efficiency of the turbine
Q is the flow of the water through the generator (m³/s)
H is the head (m)
g is the acceleration due to gravity (m/s²)
? is the density of the water (kg/m³)
Flow rate can be generated by using Equation (1.0).
Q=v × ?×D24Where, v is the velocity of effluent (m/s)
D is the diameter of connecting pipe (m)
Though, another way to obtain the more accurate value of flow rate has been implemented. Table 4.1 shown the average flow rate of effluent in unit of m³/month with refer to the monthly record from Juru STP and also with the graph of actual and average monthly flow rate of effluent is shown as Figure 4.1. The average monthly flow rate of effluent which is in m³/month is converted into m³/second to calculate the amount f hydraulic power available in the system. The average value of flow rate was classified and used in the calculation of power since it gives a long-term assessment of power generation capabilities (Marissa Capua, et al., 2014).
Year Month Flow rate of Effluent (m3/month)
2016 January 567,088
2017 January 892,744
Table 4.1 Monthly Flow Rate of Effluent (m³/month) from January 2016 until Septmber 2017 of Juru STP and the Average Flow
Figure 4.1: Actual and average monthly flow rate of effluent from January 2016 until September 2017 for Juru RSTP
The head of the effluent discharge (H) measured is 1.0 meter at Juru STP. For efficiency, ? has a value of 0.85 and it was applied in the calculation of output power for the system. The engineering firms usually implement this value to determine the estimated power generation produced by the system. According to Marissa Capua (2014), a factor of safety which refer to losses due to friction through the turbine and piping system is called the efficiency (?). Moreover, a micro hydro generator can provide a range of 60 to 80 percent of efficiency and the foremost turbines even can maximize the efficiency until 80 to 90 percent.
The water density, ? flowing through the generator is around 1000 kg/m³. According to the change in water density with respect to temperature (Marissa Capua, et al., 2014), the percent of change in density is less than 1% when the degree of temperature is around 40-degree celsius and also the Indah Water Konsortium (IWK) company recommended the density of effluent to be used is 1000 kg/m³. That why, according to all the reason stated above, this research used the density of effluent as a constant value of 1000 kg/m³ in Equation (3.0).
Temperature (°C) Density (kg/m3) % Change of Density
0 999.8 0
10 999.7 0.01
20 998.2 0.16
30 995.7 0.41
40 992.2 0.76
Table 4.2 Change in Water Density with respect to Temperature (Marissa Capua, et al., 2014)
The preliminaries data that obtained from the Juru STP is shown in Table 4.3. These data are used to calculated the estimated power output that can be generated by micro hydro generator in Juru STP. For gravitational acceleration, a constant value of 9.81 m²/s is used.
Preliminary Data Values
Population Equivalent, PE 100,000
Average Flow Rate of Effluent, Q 0.261 m³/s
Head of Effluent, H 1.0 m
Gravitational Acceleration, g 9.81 m²/s
Efficiency of Turbine, ? 0.85
Density of Effluent, ? 1000 kg/m³
Table 4.3: Preliminaries Data from Juru STP
From that preliminaries data, power output is calculated by using Equation (3.0). The values are shown in Table 4.4.
Power Output Values (kW)
Hydraulic Power available in the system, Ph 2.56
Electrical power converted from hydraulic power, Pe2.176
Table 4.4: Power output calculated
Facility Gross Head (m) Flow Rate (m3/s) Power output (kW) Reference
Emmerich, Germany 3.6 – 3.8 0.40 13 Lau, 2008
Puan Hydro, Korea 19.6 1.18 200 Lau, 2008
Poggio Cuculo, Italy 28.0 0.38 44 CITATION Ali14 l 2052 (Aline, et al., 2014)Armary, Switzerland 105.0 0.09 68 CITATION Ali14 l 2052 (Aline, et al., 2014)Marchfeldkanal,
Austria 2.0 6.00 70 CITATION Ali14 l 2052 (Aline, et al., 2014)Llys y Fran, Scotland 25.0 0.16 29 CITATION Ali14 l 2052 (Aline, et al., 2014)Sangüesa, Spain 11.0 1.16 75 CITATION Ali14 l 2052 (Aline, et al., 2014)Juru Regional Sewerage Treatment
Plant, Penang 1.0 0.261 2.176 This research
Table 4.5: Comparison of power output generated by micro hydro generator on different elevation and flow rate
The flow rate of Juru STP is 0.261 m³/s which is smaller than the flow rate of the sewerage treatment plant in Emmerich of Germany which is 0.4 m³/s and it can generate output power up to 13 kW. But according to Archana Tamrakar, et al. (2015), a low power flow rate of 0.06m³/s and a maximum head up to 30m of height can generate the power output up to 12 kW. But the possible power output of Juru STP is 2.176 kW and it cannot achieve the target power of 12 kW which means Juru STP can generate only 18.13% from the target power output. As shown in Table 4.5 Poggio Cuculo of Italy, Armary of Switzerland, Marchfeldkanal of Austria, Llys y Fran of Scotland, Sangüesa of Spain generated acceptable power output which is under 100 kW (micro hydro power) by either in high in flow rate (m³/s) or high in gross head (m). Since Juru STP has low head and low flow rate, there has small power output than target power output.
The power output obtained from this research is 2.176 kW which can be classified as pico hydro power which is not in the scope of micro hydro power. So, from this result, this Juru sewerage treatment plant is not recommended to install micro hydropower system since the power output is not satisfied. Other plants can be installed micro hydropower system if they have suitable criteria to implement. Besides, in order to get the target power output which is 12 kW in Juru STP, the minimum flow rate can be determined by using the electrical power equation which is Equation (3.0).
Pe=Ph×?=Q×H×g×?×?The required flow rate can be determined by rearranging the Equation (3.0),
Qreq =PreqH×g×?×?Electrical Power Required, Preq (kW) Head, H
(m) Gravitational Constant, g (m²/s) Density of Water, ? (kg/m³) Turbine Efficiency, ? Flow Rate Required, Qreq (m³/s)
12.0 1.0 9.81 1000 0.85 1.44
Table 4.6: The flow rate required based on electrical power required
Based on the Table 4.6, the required flow rate is 1.44 m³/s to get the target power output. Juru STP plant has a flow rate of 0.261 m³/s which is more than required flow rate. Though Juru STP has a reasonable required flow rate, this plant cannot generate target power output because of the low head.
4.3Return on Investment (ROI)The profit to a shareholder that is obtained from an investment of certain resource is known as Return on Investment (ROI). Compare to the investment capital, a high ROI can give advantages where the investment advances are more favorable. As an execution measure, ROI is used to evaluate the viability of an investment or to think about the effectiveness of various investments. In only thought as far as financial factor, it is one approach of relating benefits to capital contributed (Wikipedia, 2017).
Year Month Electrical Energy Consumption (kWh) Monthly Electrical Bill (RM)
2016 January 238,540 89,396.47
February 211,239 81,739.82
March 218,004 86,101.75
April 210,232 130,424.00
May 233,475 87,212.07
June 197,577 76,175.09
July 176,449 74,425.12
August 208,482 80,232.00
September 207,510 82,929.70
October 220,785 82,788.00
November 239,907 87,662.60
December 222,334 84,092.45
2017 January 222,334 84,092.45
February 148,611 61,116.85
March 183,248 68,959.70
April 192,098 73,233.60
May 213,867 80,670.40
June 181,849 70,099.20
July 181,478 70,521.30
August 197,511 77,347.00
September 214,004 83,403.25
Average 205,692 81,553.47
Table 4.7: Monthly Electrical Bill (RM) with respects to Electrical Energy Consumption (kWh) and its average from January 2016 until September 2017 of Juru STP
The above Table 4.7 is shown the average value of monthly electrical bill (RM) with respects to electrical energy consumption (kWh). From this table, Juru STP spent RM 81553.47 for the electrical energy of 205,692 kWh for their plant operation process.
Figure 4.2: Monthly Electrical Energy Consumption (kWh) from January 2016 until September 2017 for Juru Regional Sewerage Treatment Plant
Figure 4.3: Monthly Electrical Bill (RM) from January 2016 until September 2017 for Juru Regional Sewerage Treatment Plant
Figure 4.2 and Figure 4.3 respectively plotted the monthly electrical energy consumption and monthly electrical bill for Juru regional sewerage treatment plant from January 2016 until September 2017. Calculation of average rates of electrical bill per kWh usage is used the average of electrical energy consumption per month and average of electrical bill per month.
Details of Average Values
Average total monthly electrical energy consumption 205,692 kWh
Average total monthly electrical bill RM 81,533.47
Average rate of electrical bill per kWh usage RM 0.3964/kWh
Table 4.8: Details of average values for electrical bill per kWh usage of Juru Regional Sewerage Treatment Plant
The average rate of electrical bill per kWh usage of Juru Regional Sewerage Treatment Plant is shown in Table 4.8. From the result, Juru STP used approximately for 1 kWh is about RM 0.3964 or 39.64 sen for electrical bill.
Operation Category Total Generated Power
(kWh) Saving in Electrical Bill
Monthly 1566.72 RM 621.05
Yearly 18800.64 RM 7452.60
Table 4.9: Estimated power output for application of micro hydro generator in Juru Regional Sewerage Treatment Plant
It is proposed that one generator will run by 24 hours per day in this research. Table 4.9 shown the estimated total power generated by micro hydro generator and also estimated cost saving in electrical bill by applying micro hydro generator in Juru Regional Sewerage Treatment Plant. From the result, Juru STP will save RM 621.05 for monthly and RM 7452.60 for yearly. Compare to the electrical bill usage in Juru STP without applying micro hydro generator, it is found that 0.762% will save in electrical bill per month by applying micro hydro generator in the system.
According to the Energypedia (2015), depend on the site electricity requirements and location, from $1,000 – $20,000 which is around RM 4,061 – RM 81,221 can cost to install a small-scale hydro-power system. In this research, RM 35,000 is taken as a total investment cost for this system including maintenance fees and other construction cost.
The Juru STP will require 5 years to get the benefit from the initial investment capital of RM 35,000 from the calculation of Return on Investment (ROI) in terms of years or payback period. Marissa Capua, et al., (2014) stated that the acceptable payback period is between 0 to 10 years according to the interview with the plant manager at Deer Island in Boston of MA, Dan O’Brein. Besides, Fred Haffty, manager in Haverhill, claim that a payback period should be within the quarter of feasible lifespan of the product.
In this research, Juru STP will save in electrical bill approximately RM 7452.60 for yearly and the total investment cost is RM 35,000. As a result, the payback period is around 5 years so that is likely probable according to the payback period.
4.4Contribution of the Operation of Micro Hydro Generator on Pumping System of Aeration Tank in the Sewerage Treatment PlantThe aeration system for the operation of typical activated sludge wastewater treatment plant consume 50 percent until 65 percent of the electrical power of the system (Deepika Sandhu ; Ruchi Pandey, 2014). That why aeration system consumed a large quantity of electrical power that is more than half of the power of all the operation of treatment plant. In this research, possible saving of electrical bill payment contributing to the operation of aeration system is discussed.
From the calculation, the average minimum estimated net power consumption of aeration system is 102846 kWh and the average maximum estimated net power consumption of aeration system is 133699.8 kWh. Monthly electrical bill for this system can cost from RM 40768.15 to RM 52998.6. Applying the micro hydro generator in the STP, this system will save electrical bill from 1.17% to 1.52%. This range is not a significant for this aeration system. But the main reason to install the micro hydro power generator in sewerage treatment plants is to have a self-ecosystem electrical power generated for the electrical use in sewerage treatment plant by using its own flow of effluent by supporting the sustainable energy and energy efficient approach.
4.5Practicality of Speculative Micro Hydropower SituationsThere were three steps needed to define the practicality of installing the micro hydro generator for the speculative cases of head and flow that were set up. Firstly, potential of electrical power output generation in kWh was calculated in consideration of the possible combinations of head and flow in the ranges by using Equation 3.0. Secondly, savings is calculated by converting the values of the potential power generation values using an average rate of RM 0.3964/kWh usage. Annual saving for every speculative case is shown in Malaysia Ringgit. Finally, payback period is calculated by comparing the investment capital of RM 35,000 and the annual savings. Appendix shown the practicality of speculative cases for micro hydropower situations.
1.0 1.5 2.0 2.5 3.0 3.5 4.0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.5 2 2.5 3.0 3.5 4.0 4.5 5.0 ?8 7 6 5 4 3 2 1?
Table 4.10: The Possibility of the Different Combinations of Speculative Flow (m³/s) and Head (m)
From the Table 4.10, cases that have a payback period of 5 years or less than 5 years are assumed to be possible and cases that have 6 years or 7 years are likely possible and more than 7 years are impossible. Total of 126 speculative cases are analyzed and tabulated in Table 4.10. As a result, 96.83% are possible, 1.59% are like possible and 1.59% are impossible by changing in flow (m³/s) or head (m). As seen in the table, most of the cases are possible for 0.3 m³/s of flow rate with head of 1 m and above.
4.6Micro Hydro Generator Available in Reality between Head and Power OutputAccording to the HS Dynamic Energy CO., LTD (HK), there are two types of micro hydro turbine which can use start from low head or low flow rate. These two turbines are standard micro hydro turbine below 5kW-propeller and Customer made micro hydro turbine above 5kW-propeller.
There are three main things that need to know to install the micro hydropower system which are head, flow and output capacity. Head of the power system is the different of water flow energy between water import section and export section. The flow rate if a hydropower system is the volume of water flow that come through the turbine cross section in a unit time. The output capacity of a hydropower system is the power of the turbine shaft end connecting with the gear box or generator (HS Dynamic Energy CO., LTD, HK).
Head, H (m) Flow Rate (m³/s) Gravitational Acceleration, g (m²/s) Density, ? (kg/m³) Efficiency, ? Power Output, Pe (kW) Available Power (kW)
1 0.021 9.81 1000 0.85 0.175 0.3
1 0.023 9.81 1000 0.85 0.191 0.5
1.2 0.018 9.81 1000 0.85 0.18 0.6
1.2 0.02 9.81 1000 0.85 0.20 0.6
1.5 0.02 9.81 1000 0.85 0.25 1
1.5 0.03 9.81 1000 0.85 0.375 1.5
2 0.08 9.81 1000 0.85 1.334 2
2 0.09 9.81 1000 0.85 1.50 2
2.5 0.1 9.81 1000 0.85 2.084 5
2.5 0.2 9.81 1000 0.85 4.169 5
3 0.07 9.81 1000 0.85 1.751 1.5
3 0.08 9.81 1000 0.85 2.001 1.5
4 0.1 9.81 1000 0.85 3.335 5
4 0.15 9.81 1000 0.85 5.003 5
5 0.12 9.81 1000 0.85 5.003 5
5 0.05 9.81 1000 0.85 2.085 5
Table 4.11: The available power (kW) with respects to the flow rate (m³/s) using standard micro hydro turbine below 5 kW-propeller
The available power (kW) in application of micro hydro turbine in reality with respect to the flow rate is tabulated in Table 4.11. Juru Regional Sewerage Treatment Plant has a head of 1m but high in flow rate of 0.261 m³/s. Since the micro hydro power range is from 5kW to 100 kW, by using the standard micro hydro turbine it is likely possible but the flow rate and head should be reasonable to achieved 5 kW. Moreover, it can take long period for payback period and it cannot achieved the target power of 12 kW. So Table 4.12 was provided for other option which is using customer made micro hydro turbine above 5 kW-propeller.
Head, H (m) Flow Rate (m³/s) Gravitational Acceleration, g (m²/s) Density, ? (kg/m³) Efficiency, ? Power Output, Pe (kW) Available Power (kW)
2.5 0.18 9.81 1000 0.85 3.752 5
2.5 0.3 9.81 1000 0.85 6.253 8
3.5 0.67 9.81 1000 0.85 19.553 30
3.5 1.3 9.81 1000 0.85 37.940 40
4.0 0.2 9.81 1000 0.85 6.670 8
4.0 0.4 9.81 1000 0.85 13.342 8
5.0 1.6 9.81 1000 0.85 66.708 70
5.0 1.7 9.81 1000 0.85 70.877 70
6.0 1.95 9.81 1000 0.85 97.56 100
6.0 2.0 9.81 1000 0.85 100.06 100
7.0 2.2 9.81 1000 0.85 128.413 100
7.0 2.3 9.81 1000 0.85 134.249 100
Table 4.12: The available power (kW) with respects to the flow rate (m³/s) using customer made micro hydro turbine above 5 kW-propeller
Table 4.12 was tabulated the available power (kW) with respects to the flow rate (m³/s) using customer made micro hydro turbine above 5 kW-propeller. From the result, this micro hydro turbine is suitable for use of generating electricity in sewerage treatment plant because the head and flow rate is reasonable for most of the sewerage treatment plant.
CONCLUSION5.1SummaryFrom the result of power output, it is decently lower than the target power output which is 12 kW. Since the micro hydro power range is from 5 kW to 100 kW, the power output of this research which is 2.176 kW is not in the range of micro hydro power. Besides, payback period for this research is 5 years which is possible for having the return on investment (ROI) or attaining the profit. The output power cannot achieve the target power because of the low head in this sewerage treatment plant. Since the population is 100,000 so the flow rate of this plant for micro hydro generator is satisfied. According to the application of micro hydro turbine in reality, flow rate of 0.261 should have at least the head of 2.5 m using the customer made micro hydro turbine above 5kW-propeller. So, the output power will be 8kW which is within the range of micro hydro power. Even though the low head and low flow rate in the system, the total estimated monthly saving in electrical bill is found RM 621.05 which is 0.762% will save electrical bill for monthly. However, the power output is not in the range of micro hydro power and not achieved the target power, this research found that suitable power output generating by micro hydro generator can provide the electrical power for the internal use of sewerage treatment plant and it will help to save the electrical bill for the plant operations. In result, the effluent discharge point of waste water treatment plant has the potential energy form flowing water can utilized to implement the generation of electrical power by embedding the micro hydro generator.
5.2RecommendationApplication of micro hydro generator embedded at the effluent discharge point of the sewerage treatment plant is eminently prescribed to do more researches and configuration works. The micro hydro is renewable energy and using the micro hydroelectric generator is considered as a supportable designing towards sustainable power source and energy efficient approach so the implementation of generating electricity using micro hydro generator is highly recommended. There are some researches that proved that the possibility of generating the electrical power using micro hydro generator in sewerage treatment plant like sewerage treatment facilities in Korea, Italy, Austria, Spain, Germany, Switzerland and Scotland according to the Lau (2008) and Aline Choulot, et al., (2014). Effluent discharge of every waste water facilities may not be achievable to implement micro hydro generator but there are other opportunities to implement renewable energy. A micro hydroelectric generator exclusively may not be monetarily practical, but rather the expansion of other energy recovery systems could make the investment more beneficial. The sewerage treatment plant at Deer Island rehearses a mix of sustainable power source innovations, and these advances can possibly be connected at other facilities (Marissa Capua, et al., 2014). Moreover, investigate on the utilization of micro hydroelectric generator in different segments, for example, local utilize, business utilize and open utilize are recommended keeping in mind the end goal to give the elective method to lessen the energy use, reuse, recycle and recreate the energy. Future research performance is recommended for micro, pico or even nano hydro power production from overhead water tanks of the lavatories and kitchen to charge the mobiles and little chargeable offices. This manageable approach and configuration is in the long run encouraged in keeping the energy inadequacy issue and in this manner give advantage to all the social, nation and even for the future generation.
5.3Innovation and Commercialization
From the result of this research, the implementation of micro hydroelectric generator for constructing a business around utilizing energy in streams of waste water effluent is considered as a possible attempt. This business could undoubtedly develop into different markets, prominently the consumable public water supply in which pressure decreasing valves are utilized to diminish the pressure by dispersing energy as opposed to catching it. Most of the industries are substantially used the water for the processes so they are one of the most possible candidates for applying micro hydroelectric system. The main reason of centering the commercialization of micro hydroelectric system for sewerage treatment plant is because sewerage treatment plants are the heavy users of electricity for the operation processes and also potential energy source is available from their flowing water so it is ready to create the electrical energy using their embedded potential energy from effluent. Moreover, micro hydro systems are recommended than other energy systems because it can generate electrical energy continuously, as long as the water is flowing, and will commonly be the most cost-effective renewable energy approach.
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