The first ZEH at the Armory Park del Sol neighborhood has been monitored since its opening in April 2003. The following charts represent different periods including the:
- first year's operation when the home was open as a model and later occupied;
- first full year when the home was occupied;
- full calendar year 2004 period, and
- full calendar year 2005 period.
The data available here represents 100% of the energy used in the home for heating, cooling, water heating, laundry, cooking, lighting, refrigeration, small appliances, and all plug loads. No energy was supplied by natural gas or other fuels.
2005 Calendar Year
Now that the final data has been recorded for the calendar year 2005, the Tucson Zero Energy Home total energy costs (including heating, cooling, water heating, lighting, appliances, and general plug uses) for the year averaged $15.00 per month – even with the increasing costs for energy. Since over 80% of the house energy use was supplied by the solar systems, these costs are fixed (to the initial cost of the systems) for the life of the home. And with the modifications to the solar thermal system only completed in February 2005, the next year 2006 looks to be even better!
This data set is for calendar year 2005. Improvements to the solar thermal system were implemented near the end of February resulting in reduced use of the back-up demand heater and fewer thermal losses from the storage tank.
2004 Calendar Year
This data set is for the calendar year 2004. During this period one inverter was out for repair for a month period in May. In addition, the solar thermal system performance gradually diminished due to problems with the solar pump. This year's performance provided information that led to improvements in the solar thermal system as well as replacement of the inverters due to an incompatibility with the back-up demand heater.
First Year Occupied
This data set is for the first year when the home was occupied from October 7, 2003 through October 6, 2004. During this period one inverter was out for repair for a month period in May. This year's performance provided baseline performance information for the homeowner and researchers to better understand the energy use of the home throughout both heating and cooling periods. This year was approximately 25% hotter, based on cooling degree-days (basd 65), than long-term data (1960-90).
First Year from Opening
This data set is for first year from when the home was opened as a model on April 23, 2003. The home was unoccupied, but open for visitors and lighted and cooled until its sale in October 2003.