If you have questions about your current bills from PUD, PLVC Utilities Committee encourages you to visit the PUD website, www.jeffpud.org for a wealth of information. There are many articles of a general nature and also specifically about your bill. Start by clicking on the SMARTHUB, logging onto your account and searching around for information about your usage and billing.   Below is an article from the PUD that discusses one element of changing electric bills.

Using heating degree days verses average daily temperature to explain your high bill

While the change in the weather is the simplest reason for the rise in customer bills, it’s not that simple. There are two tools we use to inform customers about the rise in heating demand, but one is a clear standout over the other.

We use average daily temperature of comparable billing periods as a general tool on our customer statements to help them understand the impact that the weather has on their bill.  That difference between billing periods alone really doesn’t tell the whole story about how hard your heating system is working, especially on a daily basis – which is how you are billed for the electricity you use. The average can only tell a general story about your usage.

The energy industry more widely uses a measure called “Heating Degree Days”. Heating degree days allows for a more accurate means of determining fuel or electrical usage required to heat a building for residential and commercial purposes. Its a better measure of how much work your heating system has to do to keep you comfortable. A heating degrees day is the difference between the daily average outdoor temperature and a baseline indoor temperature of 65 degrees. The sum of those daily calculations for a month – or a billing period – better captures the impacts of short cold snaps than a monthly average can. To demonstrate how different this is from average daily temperature, look at this chart supplied to us by a customer:

Nov 2015   Dec 2015 % Change
Average Daily Temperature   51  42  17.6
Heating Degree Days   247  609  146.6

 Bills changed by far more than 17.6% during that period and were closer to a 150% change. Why? Much like your electric bill itself, heating degrees are additive, so it reflects your incremental or day to day usage of electricity (kilowatt hours) . An average daily temperature for a billing period does not capture the day to day impact that cold snaps have on your electrical usage because it’s an average. You are billed for your incremental use, not average use. So an energy indicator that is additive like your energy bill is going to better reflect your actual power usage.

In the new year, the PUD will resume posting heating degree day information to help make better sense of what is going on when electric bills suddenly increase. The source of data is from the City of Tacoma. Please go to our Heating Degree Report page for more information.  It is always available on our “Electric” dropdown menu.