A Trombe Wall is a way to add passive heating for colder climate homes.

The Trombe wall patented in 1881 by its inventor, Edward Morse, and popularized in 1964 by French engineer Félix Trombe and architect Jacques Michel is a sun-facing wall  with a massive wall separated from the outdoors by glazing and an air space, which absorbs solar energy and releases it selectively towards the interior at night

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