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10.3: Calculating Power Costs

  • Page ID
    7188
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    It is important for water managers to determine the potential costs in electricity for pumping water. Units used for measuring electrical usage are typically in kilowatt-hours (kW-Hr). In order to convert horsepower to kilowatts of power, the following conversion factor is used.

    1 horsepower = 0.746 kilowatts of power

    Once you know the hp that is needed you can then determine the amount of kW-Hr needed. Then, costs can be determined depending on what the local electric company charges per kW-Hr. Water utilities will calculate estimated budgets for pumping costs since these are typically the largest operating costs.

    Exercises

    Solve the following problems.

    Pump

    Flow Rate

    Hp

    Efficiency

    Run Time

    Total Cost

    1

    500 gpm

    50

    2

    1,000 gpm

    75

    4

    2,000 gpm

    250

    Well

    Flow (gpm)

    Run Time (Hr/Day)

    Wire-to-Water Eff

    Head Pressure (psi)

    hp

    Cost/Year ($) @ $0.135/kW-Hr

    A

    750

    18

    68%

    110

    B

    1,800

    13

    61%

    85

    C

    2,750

    12

    57%

    95


    10.3: Calculating Power Costs is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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