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Solar Thermal Collectors area in EnergyPlus

asked 2021-02-23 07:34:28 -0500

anonymous user


updated 2021-03-29 08:38:40 -0500


The building's roof has an area of 600 squared meters and is divided into 10 zones (which is 60m^2 for a zone)

I need to install a solar thermal collector (Flat Plate with area of 2m^2) and the software says that i must put every solar thermal collector in different surface

For example: Collector1 in Roof zone1, Collector2 in Roof Zone2, Collector3 in RoofZone3 etc etc etc etc

Question 1) Why i can't use the same zone for more than one collector, because one Zone is 60 m^2 and the solar thermal is 2 m^2), is this a constraint from the Software EnergyPlus? Because for PV this wasn't a problem at all, only for solar thermal is

Question 2) I need to install 35 solar thermal collectors on the entire roof, but i cant add more than 10, what should i do?


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answered 2021-02-23 09:26:43 -0500

The answer in this post about solar collectors mentions that you can assign collectors to building surfaces like roofs OR shading surfaces. This is also supported in the Input Output Reference document for EnergyPlus, specifically the description of the Surface Name input field of the SolarCollector:FlatPlate:Water object.

In your case, it sounds like adding 35 shading surfaces each with an area of 2 m^2 above the roof is your best option. Each of those shading surfaces would then be assigned to a flat plate solar collector (35 total of those as well).

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Thanks it was helpful

anonymous userAnonymous ( 2021-02-24 05:17:43 -0500 )edit

answered 2021-02-23 19:33:40 -0500

Perhaps I am misunderstanding your question, but if you have 35 individual collectors in a single solar thermal system, you could just use a single SolarCollector:* object to represent the entire system. You don't need to use multiple SolarCollector:* objects. And then you could reference a single shading surface.

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Thank you for the reply, it was very helpful,

I would like to ask also the following,

i am designing a building in which part of the DHW will be from Solar Thermal and the other part will be from the boiler (fuel),

1) Where can i Limit the capacity of hot water produced only by Solar thermal collectors?

Is it in the WaterHeater:Mixed part ---> In the Use Side Design Flow rate and Source Side Design Flow Rate Fields? Do i need to limit here the m^3/s for the both?

2) Also do i need to put two tanks in WaterHeater:Mixed (one tank connected with solar, the other connected with boiler)?

anonymous userAnonymous ( 2021-02-24 05:17:19 -0500 )edit

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Asked: 2021-02-23 07:34:28 -0500

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Last updated: Feb 24 '21