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How to estimate Domestic hot water energy consumption respect to people occupancy ?

asked 2021-07-15 03:19:22 -0500

Hardik gravatar image

updated 2021-07-23 12:42:47 -0500

I have put types of equipment: clothes washer, Dishwasher, sinks, shower, baths in my model. In that model, outputs = Peak Flow Rate(m3/s) * Flow rate fraction schedule * target temperature

Also, I have some questions regarding the Flow rate fraction schedule. what should be fraction values? should we consider different target temperatures regarding winter, summer, transient?

Apart from my recent model, I want to estimate energy consumptions with respect to people's occupancy. is it possible in energy plus? if yes, give me a suggestion of what should I do?

Thank you for your supports

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answered 2021-07-15 16:32:21 -0500

sashadf1 gravatar image

Regarding your question on estimating energy consumption with respect to people's occupancy, you can look at the people object here:

The actual occupancy, as a function of time (i.e. at each timestep), in a thermal zone that has been assigned a people object statement is calculated through multiplication as described below.

The Number of People Schedule "values can be any positive number," and the "actual number of people in a zone as defined by this statement is the product of the number of people field and the value of the schedule specified by name in this field."

So, some steps for you are to:

  1. decide what thermal zones are going to be occupied.

  1. figure out what the nominal or design occupancy will be and how you are going to calculate it (People, People/Area, or Area/Person method).

  1. decide on an occupancy schedule that will be referenced in the Number of People Schedule Name field.

In this occupancy schedule, you can specify if your building is occupied from 8 am - 5 pm (working hours), after hours, etc. If occupancy changes throughout the day (is your building more heavily occupied in the morning vs afternoon?) you can implement this by specifying the actual values of the schedule referenced by the Number of People Schedule Name field at each timestep.

You can also distinguish between weekdays vs weekends vs holidays using the schedule object.

"Note that while the schedule value can vary from hour to hour, the number of people field is constant for all simulation environments."

In order to determine the impact of people occupancy on energy consumption, try plotting the occupancy (nominal occupancy*schedule fraction) in each zone with kWh of electricity for different end-use subcategories (lights, space conditioning, etc.). Try changing the nominal occupancy value for each thermal zone or the schedule fractions to see how that impacts your model.

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Asked: 2021-07-15 03:19:22 -0500

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Last updated: Jul 15