La Luz – The Passive Solar Experience 2025

A La Luz winter morning looking North.  Photo courtesy of Jim Wilson.

by Pat Gallagher

In early summer, I was invited to give a short talk about La Luz at a symposium on Ambient Energy. This is a fresh new name for Passive Solar, which is mostly about using the sun to make a home or office more comfortable. In the extreme, it could be about a zero-energy architecture; but in reality, it means making the most of natural energy, night and day, winter and summer. 

The Symposium was sponsored by the University of Louisville-JB Speed School of Engineering. Numerous New Mexico architects and builders (passive solar pioneers) helped organize the Ghost Ranch gathering in September 2025. It was an overdue sequel to a similar meeting 50 years ago also held at Ghost Ranch, about the same time La Luz was completed.

My contribution to the symposium was to give a quick history of the people and ideas that created La Luz, with a bit about how well the design fits into living with the Sun. 

In about 1967, the late architect Antoine Predock along with Didier Raven, and Ray Graham put together a design, a development plan, and the adobe reality of La Luz. At that time, it was daring, futuristic, and difficult to finance. They included all the elements of a passive solar home: adobe walls, brick floors, and large sun-catching windows. Site orientation for optimum sun exposure gave way to favoring elegant views of the Sandias. As a result, the passive solar goodness was and is today demonstrated best on winter mornings, and by shorter heating and cooling cycles each year.

Putting together the talk and listening to the other presentations, gave me a better understanding of adobe construction. The magic of living with earthen walls, led to a dive into how adobe gathers, holds and releases heat and humidity. Cinder block, brick, and wood framed walls cannot do this. In fact, adobe delays the movement of heat from minutes (with framed walls) to hours. Early on a winter day, the sun heats the floor, the air and furniture nicely. Then about when the sun is going down, the adobe begins to pour its “latent” heat into the house. In La Luz, this delays when one needs to kick in the central heating. 

In the summer, the carefully considered overhangs block the midday sun along with the owner’s moveable interior shades to complete the job. Night sky cooling and well-planned night ventilation pull the adobe temperature down before the cycle begins again.

These built-in but largely ignored capabilities make La Luz a functioning example of how passive solar works and how it quietly reduces heating and cooling costs.

Taos Pueblo —  Photo courtesy of Jim Wilson

A visit earlier this year to Taos Pueblo offered a startling similarity to La Luz. The passive energy aspect aside, the individual residents of Taos Pueblo carry the responsibility of protecting their own walls from the weather. This multi-story group of adobe buildings was built more than 300 years ago! In La Luz we too carry the same responsibility, for our own adobe walls.

​We use stucco, Taos uses mud. ​

For this to work, the community must sustain an agreement lasting generations that will keep the community from literally disintegrating. La Luz at 57 demonstrates how community efforts at preservation can and do work to keep our adobe magic alive and strong.

In closing, I put a picture on the screen of the Zome Climber (circa 1975) here at La Luz. It was designed and built for us by Steve Baer. Steve was one of the creators of the first Passive Solar Conference held at Ghost Ranch 50 years ago.

Zome Climber- Photo courtesy of La Luz del Oeste Foundation

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 The View: Volume 1, Issue 1

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about the author: 

Pat Gallagher, BS Mechanical Engineering, University of Michigan 1973, has fifty years of technical experience primarily in research and development, and design engineering. While employed at Ford Motor Company, Motorola, Boeing and smaller companies, his life’s work involved the planning and completing of large projects in automotive structures, solar energy, kinetic energy storage, robotics and industrial automation. He is currently involved in La Luz Landowners Association, having chaired the External Affairs Committee dealing primarily with formulating city zoning regulations, and having chaired the Maintenance Committee with an emphasis on long and short-range project planning, design, budgeting and implementation.