Using Degree Days to Measure Savings

Steve Garson

Now that my steam system is tuned up and using low pressure, good vents, etc., I would like to figure out what it really will mean in $$. I know that degree days are used to measure the need for heating.

How can I use this data along with my oil BTU usage to see if my work is really saving money?

Chuckles_3

I am not sure I understand the question, unless you are asking how to do the math.

Take the number of BTUs or therms used in any winter period, and divide it by the total number of degree-days in the same period.

Do the same calculation for before and after the upgrade. (The number of days in the period doesn't really matter, so you can do it for a 28-day billing period last year and a 31-day billing period this year, if you like, it doesn't affect the result.)

If you are using 15% fewer "BTUs per degree day" after the upgrade, you are saving 15%.

Confused_3

I've got gas, so it's a bit easier to calculate the amount used--but you can do similar based on delivery dates and amounts. I see no reason to calculate BTU per heating degree day, I would just calculate gallons/HDD, but it is easy to do. Each gallon of heating oil is approximately 139,000 BTU.

Get your old oil delivery slips (or call your oil vendor, they'll have the info as they use it to calculate when to make your delivery). From this you can calculate the number of gallons used between 2 fill dates.

Then figure out the number of heating degree days for the same period. The easiest source I know for historical info is http://www.weatherunderground.com Put your zipcode in the "Find weather..." box up at the top left. Now scroll down and hit GO next to "detailed history and climate". Now click on "custom" in the new page, then enter the correct date range in the FROM and TO boxes and again click GO. The heating degree days for the period are then shown in the SUM column.

Just divide the total gallons (or BTU) you used by the number of heating degree days to calculate a good measure of how much oil you used per HDD before and after your upgrade.

VT

[Deleted User]

The easy way

is to call your delivery company. Ask for a record of your delivery history. Most will fax or e-mail to you.

If you want to DIY - divide degree days by gallons. The larger the number, the more you're saving.

powerhead

Degree Day/ K-Factor

> is to call your delivery company. Ask for a

> record of your delivery history. Most will fax

> or e-mail to you.

>

> If you want to DIY - divide

> degree days by gallons. The larger the number,

> the more you're saving.




Is this " larger number" the K-Factor that I see on my delivery slip?