If you know you ought to be doing more to help slow global warming but just can’t quite get motivated to make drastic lifestyle changes, stop by the Corrales Comment/Radford residence some afternoon. It’s an owner-built passive solar home, and this time of year a crucial part of it undergoes super-heating in preparation for winter. The idea is to deliver as much heat as possible to thermal mass inside the home —meaning adobe wall, brick floor and even an old-fashioned cast iron bathtub— without overheating the rest of the home.
This time of year, the attached greenhouse is closed up tight to trap as much of the sun’s heat as possible and allow that to super-heat the adjacent bathroom which was designed to be the major source of warmth during winter months, gradually releasing heat to bedrooms, living room and kitchen.
In mid-afternoon September 18, the temperature in the greenhouse was 124 degrees F. Maybe if you stood there for even a few minutes, you might feel motivated to act on climate change.
No one is suggesting that typical temperatures in Corrales might top 120 degrees on a regular basis during the next 30 years, but there’s little doubt but that it will get much hotter. You wouldn’t like 124.
But you probably would like a bathroom at 100 degrees when you stepped out of the shower. You’d hardly need to towel off.
All summer, the insulated sliding glass door between the bathroom and the greenhouse had remained closed so heat didn’t reach interior rooms. And the greenhouse windows were open, assisted by a ceiling vent. To keep summer temperatures down, the greenhouse has a series of small fans —powered by a solar electric panel on the roof— to expel hot air when unwanted.
Tomato plants, collards, chile peppers, kale, herbs and other foods produced in their respective seasons, and beyond. A tomato plant growing for the past 18 months had blossoms September 18. Red chile peppers on two plants were ready to harvest as more blossoms opened. Once, a collard plant grew for three years, attaining an extraordinary size.
But come fall, most of the vegetables and flowers must give way to the new priority: home heating without burning fossil fuels. Although —full disclosure— the home and newspaper office are served by a conventional natural gas heater as back-up. Even then, the hot water pumped from the heater to rooms via radiant in-floor tubes is pre-heated with a roof top solar collector.