Opening of Qualifications - WWTP CSO Tank RFQ Guaranteed Savings Contract Proj No. 121-071-A - Kokosing Ind.

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Alder Pump Station VFDs VFDs are being installed on the three 250 hp motors. The savings from the VFD large occur during the start of each motor and trader dry weather conditions, when the flow is pumped to the lower head WWTP. Under all weather conditions, one pump is operating, two are stand-by. Alder pumps operate 24 hours of a day. The calculations below show the energy usage for constant speed pumps vs adjustable speed. Constant Speed Pump Pump 1 Dry Weather 250 hp * 0.745 hp/kW * 24 hr/day * 0.6*365 days = 978,930 kWh / year Pump 1 Wet Weather 250 hp * 0.745 hp/kW * 24hr /day * 0.4*365 days = 652,620 kWh/hr Total Power usage: 1,631,550 kWh/hr Adjustable Speed Pumps Pump 1 Dry Weather 166 hp * 0.745 hp/kW * 24 hr/day * 0.6*365 days = 650,009 kWh / year Pump 1 Wet Weather 250 hp * 0.745 hp/kW * 24hr /day * 0.4*365 days = 652,620 kWh/hr Total Power Usage: 1,302,629 kWh/yr Savings from VFD = 328,921 kWh/hr @ $0.104343 kWh = $34,320 per year Operational Savings. We additionally work to identify areas where the improvement will positively impact the daily workload of Operators. These are items such as reduced activity per week, reduced time per activity, reduced overtime hours, reduced number of people to complete a task. These savings cannot be identified without input from South Bend's Operators. The following is an example of reduction of operator cost for replacement of a problematic pump station for Hobart. Analysis of pump station data from 10/ 1/2018-417/22 defined weather as periods where the pump flow rate was less than 2,500 gpm. The threshold was selected based on the apparent deviation from standard dry weather diurnal curves and confirmation of the observation by operations leaders. Over the total of 30,797 hours considered, 19,044 (62%) were classified as dry weather and 11,753 (38%) as wet weather. For the purposes of these calculations, a 62138 split between dry and wet weather was used. The labor cost to the city averages $45/hr, including fringe benefits. As wet weather operations requires around the clock attention, overtime charges are frequently incurrent. Overtime is paid at 1.5x normal wages or $67.50/hr. Consequently, it is assumed that 16 hours (2 people for 8 hours) is paid at the standard $45/hr and 32 hrs (2 people for 16 hours) is paid at the premium rate of $67.501hr Dry Weather Labor 365 dayslyr * .62 * 4 his/day * $45/hr = $40,734 Wet Weather Labor 365 dayslyr " 0.38 * (16 hrs/day * $4511ir + 32 hrs/day * $67.50/hr) _ $399,456 Existing Total Labor = $40,735 + $399,456 = $440,191 The standard expectation of man -power for a typical pump station the size of the Main Lift is 1- hr per day for 2 people + 4 hrs per month for 2 people. This is regardless of weather conditions utilizing SCADA and other automation to operate the system, Future Typical Labor Costs = 1 hrlday * 1 person * 365 days/year + 4 hrsimonth * 2 people * 12 months = 461 hrs/ year * $45/hr = $20,745 / year Consequently, the costs for the operation of the Main Lift is the difference between the expected standard operation and the actual operation: The Savings Estimate is the sum of the Future Capital, Energy, and 0&M savings and is incorporated directly into the contract. The total savings must be greater than the cost of the project, generally including engineering and financing. Because the Future Capital cost is part of the equation, we are confident that the total savings will comfortably exceed the project cost. SOUTH BEND, INDIANA GSC 53