Cochise College-  Physicsweb
               Physics Educational Resources 
 
                        Roger Weller, geology instructor
                         
wellerr@cochise.edu
                          copyright 2007-R.Weller  

                                    Home Energy Costs
                based on residential rates in Sierra Vista, Arizona for December, 2006

Approximate Rates:

1 kw.hr of electrical energy = $.11 (service charge and tax is $13.00)

1 therm of gas = $1.40 (includes cost + delivery charge)
(service charge and tax is $13.00)

Calculations for Residential Heating:

1000 kw.hr of electrical resistance heating is $110.00
(plus $13.00 service charge and taxes)

1000 kw.h of gas heating (100% efficiency-unvented) = $47.88
(plus $13.00 service charge and taxes)
(34.2 therms)

1000 kw.hr of gas heating (80% efficiency-vented) = $59.85
(plus $13.00 service charge and taxes)
(42.75 therms)

Conversions:

1 kw.h 3.6 x 106 Joules


1 kw.h = 0.0342 therms

100,000 BTU = 1 therm

1 kw.h = 3420 BTU

1 kw.h = 861 kilocalories