image107

appliance demand compared to temperature

The GasTrac Feature

  • GasTrac records outdoor temperature along with appliance demand. 
  • Appliance consumption can be compared to local temperatures.
  • Typically, analysts use regional (airport) weather, which can be very different to weather experienced at the test site. GasTrac removes this source of error.

What the Chart Shows

  • In the sample plot above appliance consumption was recorded for a year along with outdoor temperatures. The Y axis is daily demand (GJ) and the X axis is the average daily temperature.
  • The green line is consumption from the hot water tank. There is clearly no correlation between ambient temperature and hot water usage.
  • The red line shows gas consumption from the furnace. There is a strong correlation between weather and gas usage in the furnace.
  • Other appliances (fireplaces, cook tops, swimming pools) can also be monitored for correlation to weather.

Why it is Important

  • Many gas utilities apply algorithms to historic data to normalize for weather.
  • Prior to GasTrac, weather normalization was applied to the entire historic demand data record.
  • GasTrac now allows users to determine what percentage of the data should be weather normalized, which will lead to more accurate demand forecasts.

Key Points

  • Not all gas usage correlates to weather 
  • Hot water demand in the summer is identical to hot water demand in the winter