The HMS only effects the heating system's response to cold outdoor air temperature (
heating degree days) while other building characteristics, such as the occupancy rate and thermal response, had minimal variations after the retrofit, so a two-parameter model using
heating degree days was used:
Where [HDD.sub.r] and [CDD.sub.r] are monthly
heating degree days and cooling degree days respectively for region r.
Roback [1982] found that
heating degree days, total snowfall, and the number of cloudy days were positively correlated with wages, suggesting these are disamenities.
In principle we could simply find the ratio of energy usage to
heating degree days using on-site weather data, and multiply by the HDD associated with the TMY3 file (See Equation 1).
Where [HDD.sub.i] and [CDD.sub.i] are monthly
heating degree days and cooling degree days respectively for region i where regions are defined as the area served by a particular power distribution company, in this case, KESC, [T.sub.i], is the monthly average temperature of region i, [T.sub.b] is the base temperature, m is the number of days in the month under consideration, y is a binary variable that equals 1 if [T.sub.1] < [T.sub.b] and 0 otherwise.
An example of a building striving towards net zero space heating is the recently completed Material Testing Laboratory (MTL) in Hamilton, Ontario (3600 annual Celsius
heating degree days).
[[beta].sub.h] = daily consumption per
heating degree day ([m.sup.3]/[degrees]F day)
LOGAN, IA: Monthly total
heating degree days, [online] [cited 05 October 2012].
There were 20 percent fewer
heating degree days in the first half of 2012 than in the first half of 2011, Unitil said.
Double-cropping is not used in this area, generally because there are too little
heating degree days. However, a recent study of the last ten years'
heating degree days showed that 80-day hybrids harvested at 35% to 40% moisture content will allow for double-cropping of corn as far north as northern Illinois.
Lower gas therm sales in the Company's utility service territories reflect the effect of warmer temperatures in 2010, where there were approximately 22% and 12% fewer
Heating Degree Days in the the three and six month periods, respectively, compared to the prior year.
Riker says the company already has created more than 500 customized indexes for five industries, based on weather correlations over specific time periods to benchmarks such as
heating degree days. North America is the focus now, he says, and expansion to global markets "will be limited to where there is good weather data."
