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Re: [EnergyPlus_Support] Re: Import of actual-measured data



I disagree with this approach for measured data!
If you simply change the HVAC to match the measured than you are neglecting the envelope and internal loads. The importing of a schedule file to change the thermostat settings to adjust the HVAC to match measured data poses the problem where you could have a building with very different loads and the same temperatures by having the HVAC system using much more energy than it actually would. 

If you want to "set the whole model to run, giving me the indoor temperature, as I measured it" 
Start with creating a model that matches your building size, orientation, aspect ratio, people/lighting/equipment loads, run the slab calc for ground temps, = and simulating it with actual weather data (AMY) then set outputs for air temperatures comparable to your thermostat. For instance-- you could use a room air model to stratify temperatures for sensor location, or could used a mixed air model if you have several measurement points that you aggregate, or if you have surface and air temps than aggregate them and output operative temps. 

Then take your measured data- normalize it to hourly time bins and plot a chart with your measured data vs modeled data. Review in D-view software or your favorite charting tool. Lastly-- find the points where your model deviates from the measured data and change model inputs to further align the data sets. 10% would be a good degree of accuracy. The changes that are unknown and could be adjusted are insulation conductivity (for thermal bridging) COP, nominal efficiency (for HVAC) infiltration, people/equipment/lights schedules. 
It is possible to use an optimization tool such as genopt to solve this type of problem-- 

Keep in mind that modeling is designed to show typical conditions for a given set of inputs- this means that you need to get your inputs right (a difficult task for most complex existing buildings) and then you need to use actual weather data so that you can get results for an actual time and not a theoretical typical.

Hope this helps. 

On Sat, Mar 16, 2013 at 7:17 AM, George Georgiou <georgiou.geo13@xxxxxxxxx> wrote:
 

I tried to import the data with the schedule:file, but I couldn't. There is limited documentation on how to import the data and set for an ideal hvac template.

My issue is how to set the whole model to run, giving me the indoor temperature, as I measured it.




--
Jeremiah D. Crossett  | Senior Analyst  |  Phase Change Energy Solutions
120 E. Pritchard St.  | Asheboro, NC 27203  | Mobile 503-688-8951
  


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