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# One-time peak demand tariff calculation

I am analyzing a building for which the electricity demand tariff is calculated only based on the one-time highest monthly peak calculated over 15 min intervals. It is my understanding that the "Demand Window Length" specified in the tariff object counts every single one of the peak occurrences exceeding that window which is way higher than what a one-time demand charge would be. Is there a way to force the tariff to only calculated the peak demand for a one-time monthly occurrence?

Also, based on this post it looks like there is no way to get hourly data out of E+. I need that hourly data to:

1. Potentially adjust the demand window length to different values and check which one comes closer to the one-time peak demand calculations

2. Visualize the hourly data for the client since the project has weird schedules which is not possible with only the monthly tariff calc outputs E+ spits out.

Any thoughts?

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@JasonGlazer and @David Goldwasser, I know you both have posted about this before. Any suggestions on how to effectively get that hourly data out?

( 2016-09-13 08:39:45 -0500 )edit
1

could you use:

UtilityCost:Charge:Simple,
Annual Demand,           !- Name
Annual Tariff,           !- Tariff Name
totalDemand,             !- Source Variable
Annual,                  !- Season
DemandCharges,           !- Category Variable Name
\$/kW;                    !- Cost per Unit Value or Variable Name
( 2016-09-13 10:20:44 -0500 )edit
1

with:

UtilityCost:Tariff,
Annual Tariff,           !- Name
Electricity:Facility,    !- Output Meter Name
kWh,                     !- Conversion Factor Choice
,                        !- Energy Conversion Factor
,                        !- Demand Conversion Factor
,                        !- Time of Use Period Schedule Name
,                        !- Season Schedule Name
,                        !- Month Schedule Name
QuarterHour;             !- Demand Window Length
( 2016-09-13 10:22:10 -0500 )edit
( 2016-09-13 13:09:16 -0500 )edit

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I think setting the Demand Window Length to QuarterHour is exactly what you are looking for. It takes the highest quarter hour for the month and uses that for the demand computation in the UtilityCost:Tariff object. Please be aware that the timestep set in in TimeStep object should be 4 or 12.

There currently is no way to get hourly energy costs from the UtilityCost:Tariff object. If you would like to see that added you can vote for it here.

If you are just looking for hourly electrical energy or demand data, that is available. See the Electricity:Facility meter.

more

Thanks for confirming my thoughts, originally I thought the object adds up all the occurrences of the demand exceeding the window but now I realize it only picks the one that has the highest peak demand which is exactly what I needed. Voted for the new feature to be added.

( 2016-09-13 13:08:52 -0500 )edit