QOI Report peak kW conversion inconsistency?

[afontani]

The peak kW seem results seem to be high. The query (line 185) has ReportingFrequency='Hourly', but I think it should be ReportingFrequency='Timestep' as the unit conversion step (line 195) includes the number of timesteps per hour. I think there might be a 4x difference in the results.

resstock/measures/QOIReport/measure.rb

Lines 185 to 195 in e0050be

	query_str = "SELECT VariableValue/1000000000 FROM ReportMeterData WHERE ReportMeterDataDictionaryIndex IN (SELECT ReportMeterDataDictionaryIndex FROM ReportMeterDataDictionary WHERE VariableType='Sum' AND VariableName IN ('Electricity:Facility') AND ReportingFrequency='Hourly' AND VariableUnits='J') AND TimeIndex IN (SELECT TimeIndex FROM Time WHERE EnvironmentPeriodIndex='#{env_period_ix}')"
	electricity_total_end_uses = sqlFile.execAndReturnVectorOfDouble(query_str).get
	steps_per_hour = 6
	if model.getSimulationControl.timestep.is_initialized
	steps_per_hour = model.getSimulationControl.timestep.get.numberOfTimestepsPerHour
	end
	# ELECTRICITY
	timeseries['total_site_electricity_kw'] = electricity_total_end_uses.map { |x| x * 1000000000.0 / (1000.0 * (3600.0 / steps_per_hour)) }

[joseph-robertson]

Is the solution here to:

• (A) request only "hourly" Electricity:Facility timeseries and set steps_per_hour=1, or
• (B) request only "timestep" Electricity:Facility timeseries (could be hourly or subhourly), get steps_per_hour, and then refactor the timing, average_daily_use, and average_daily_timing methods to support subhourly timeseries?

[shorowit]

Note that the OS-HPXML reporting measure produces summer/winter peak electricity outputs.

[joseph-robertson]

@afontani Here is an implementation of (B) from above: #888.

[shorowit]

Do (A) and (B) basically give the same answer, but (B) is slower?

[joseph-robertson]

I think (A) and (B) could theoretically give different results. Consider the following example for kWh during the first 2 hours:

Hourly: 0.75, 1
15-minutely: 0, 0.75, 0, 0, 0.25, 0.25, 0.25, 0.25

Then kW would be:

Hourly: 0.75, 1
15-minutely: 0, 3, 0, 0, 1, 1, 1, 1

Hourly would assign peak at hour 2, while 15-minutely would assign peak at hour 1.

[joseph-robertson]

Leaning toward just calculating based on hourly timeseries. Which means the PR goes away, and we just need to hardcode steps_per_hour=1.

[joseph-robertson]

Some of the QOIReport measure outputs could probably be adopted into the OS-HPXML workflow (where we might also be able to avoid getting timeseries output).

[ejhw]

we just need to hardcode steps_per_hour=1.

@joseph-robertson Would this mean you can't run ResStock with a 15-min timestep, or is the hardcoding just for the reporting measure?

[joseph-robertson]

Just for the reporting measure.