Armory Park del Sol

Tucson, Arizona

The Armory Park del Sol homes 

feature roof top solar electric and 

solar hot water panels, which are 

hidden from the ground.

Zero Energy Home 

Soaks Up the 

Southwestern Sun

T he rooftops in Tucson’s Armory 

Park del Sol neighborhood are 

soaking up sunlight and generating their 

own power. The builder, John Wesley 

Miller Companies, combined traditional 

Mission style architecture with the latest 

energy efficiency components and 

techniques – then added solar energy 

to the all-electric homes to generate 

electricity and heat the air and water.

Every home in the development is 

highly energy efficient – using roughly 

50% less electricity than average 

area homes and qualifying for Tucson 

Electric Power’s lowest electric rate. 

Solar hot water and solar electric panels come as a standard feature on all 

the homes. The panels are rooftop 

mounted on the flat rooftops typical of 

the area.

While these homes boast energy 

performance way beyond most new 

construction, John Wesley Miller 

Companies wanted to push the envelope of home design even further. One 

of the homes was specially designed 

and engineered to use zero net energy 

over the course of a year – a Zero 

Energy Home. Just like a typical home, 

this Zero Energy Home is connected 

to the utility. At times the home draws 

electricity from the utility, and at other 

times, when the home makes more 

electricity than it uses, it rolls the 

home’s utility meter backward. 

To master the challenges of building 

a Zero Energy Home, John Wesley 

Miller turned to the U.S. Department 

of Energy’s Zero Energy Homes initiative to tap into the latest R&D from 

DOE’s labs. The NAHB Research 

Center, working closely with National 

Renewable Energy Laboratory 

researchers, Devereaux Architects, and 

a team of subcontractors and suppliers, were able to balance aesthetics 

and efficiency in the home design.

Bringing you a prosperous future where energy is clean, 

abundant, reliable, and affordable 

“What we’re literally doing 

here is building a small power 

plant one house at a time.” 

– John Wesley Miller, president, 

John Wesley Miller Companies
Produced for the 

U.S. Department of Energy 

by the National Renewable 

Energy Laboratory, 

a DOE national laboratory

DOE/GO-102003-1829

December 2003

Printed with a renewable-source ink on paper containing at 

least 50% wastepaper, including 20% postconsumer waste

Key Features

Energy Efficiency

Appliances ENERGY STAR® horizontal axis washer, 

dryer, refrigerator, dishwasher

 Ceiling/Attic/ 

 Roofing

Three-ply built-up roofing with reflective 

coating 

Radiant barrier roof decking

R-41 fiberglass batt ceiling insulation 

 Walls Solid-filled masonry block

R-14, 2” polyisocyanurate exterior 

insulation

 Windows Low-e, argon-filled, U-factor 0.32, 

SHGC 0.35 

Minimal glazing on south and west

Heating/Cooling Tankless water heater to boost water 

temperature from solar for space heating 

(see below) 

18 SEER A/C unit with variable speed 

blower, Puron refrigerant

Efficient ceiling fans

Lighting Fluorescent lamps and fluorescent 

fixtures 

Photovoltaics 4.2-kW photovoltaic array, roof-mounted 

Two 2.5-kW inverters 

Solar Domestic 

Water and Space 

Heating

Four, 4’ by 8’ solar water collectors, 

unpressurized, drainback system

210-gallon hot water tank with heat 

exchanger supplies hydronic space 

heating

Short hot water plumbing runs in conditioned space

Polyethylene (PEX) 3/8” diameter tubing 

for hot water pipes

A Strong Energy Portfolio 

for a Strong America

Energy efficiency and clean, renewable 

energy will mean a stronger economy, 

a cleaner environment, and greater 

energy independence for America. 

Working with a wide array of state, 

community, industry, and university partners, the U.S. Department of 

Energy’s Office of Energy Efficiency and 

Renewable Energy invests in a diverse 

portfolio of energy technologies.

Zero Energy Home Contacts

Lew Pratsch

U.S. Department of Energy

1000 Independence Ave. SW

Washington, DC 20585

Phone: 202-586-1512

Lew.Pratsch@hq.doe.gov

Tim Merrigan

National Renewable Energy Laboratory

1617 Cole Blvd.

Golden, CO 80401

Phone: 303-384-7349

tim_merrigan@nrel.gov

Research that Works

Working from scratch, the team devised 

a 1,718-square-foot floor plan that offers 

three bedrooms, two full baths, high 

ceilings, an open great room, a private 

master suite, and outdoor living spaces.

The home features a 4.2-kilowatt photovoltaic array and an integrated solar 

water and space heating system. The 

solid masonry construction with insulation and efficient windows keeps out 

unwanted heat, along with a reflective 

roof coating and radiant barrier roof 

decking. ENERGY STAR® appliances, a 

very high efficiency A/C system, and 

soft white fluorescent lighting perform 

well but use minimal electricity. 

The home is expected to use 7,000 

kilowatt-hours of energy annually, compared with 18,000 kWh for a conventional home in Tucson. NAHB Research 

Center engineers are monitoring the 

home’s performance; details are available at www.toolbase.org/ZEH.

The Zero Energy Home cost about 

20% more to build than the other homes 

in Armory Park del Sol. The home sold 

in less than a month to owners who like 

that it looks like a conventional home, 

yet is a Zero Energy Home powered 

by the sun. In summer 2004, after the 

home has been occupied and monitored 

for a full year, engineers will know if the 

home met the net zero energy goal.

The home’s A/C unit (center) and an 

integrated solar water and space 

heating system. Solar collectors 

provide space and water heating with 

backup heat provided by a tankless 

water heater (white square on wall).

About Zero Energy Homes

To take U.S. home energy performance 

to a higher level, DOE created the Zero 

Energy Homes (ZEH) initiative, bringing 

the latest R&D out of the laboratory and 

into homes. Both energy efficiency and 

renewable energy technologies - like 

solar water heating and solar electricity 

- serve these homes. DOE’s goal is to 

help builders create homes that produce 

as much energy as they use over the 

course of a year. ZEHs are connected 

to the utility grid, and some are even 

energy generators, rolling the utility 

meter backward when they produce 

more electricity than they consume.

DOE selected four teams that are working with researchers at the National 

Renewable Energy Laboratory to introduce the ZEH concept into the singlefamily, new-home construction industry. 

The four teams are ConSol, Stockton, 

California; Davis Energy Group, Davis, 

California; NAHB Research Center, 

Upper Marlboro, Maryland; and 

Steven Winter Associates, Norwalk, 

Connecticut. 

For more information: 

Building Technologies Program

www.buildings.gov

Select Programs & Initiatives

Project Information

NAHB Research Center

Jeannie Leggett Sikora

400 Prince George’s Blvd

Upper Marlboro, MD 20774

Phone: 301-430-6322

jsikora@nahbrc.org

www.nahbrc.org

John Wesley Miller Companies

www.armoryparkdelsol.com

Phone: 520-798-7607