Im considering building a freestanding mass wall / trombe wall with insulated masonary floor componet . It will be detached from the house and the heat gains will be ducted into the house and cold air will return also . The house is oriented in the wrong direction . I think some mechanical / electrical componets will also be incorporated to open and close insulated vents as temps rise and fall in the heating and storage cycle . Just hoping to discuss this with others to see if my idea is viable . To describe my idea I should say the collector will be highly insulateD and contain about 600 sq ft of masonary surface painted black and incased in insulated galss facing south . The walls will be insulated as will the concrete slab this is built on . Im looking at 16ft long x 8ft tall with a floor collection surface also .
Freestanding, as in separate from the house envelope? That sounds like a terribly inefficient and possibly ineffective system. Trombe walls are generally low-temperature, and the losses of collecting heat from it and moving it somewhere else may negate the gains, or at the least make it relatively very expensive for the heat gained. A trombe wall is designed to work by collecting and directly radiating heat to the space around or behind it.
If you really can't put solar collector surface attached to the house (maybe by means of a triangular addition), I would suggest lightweight solar collectors feeding the heat to storage inside the house envelope, so storage losses are not wasted. A freestanding trombe wall would be losing heat and cooling off all night, to no benefit whatsoever. Keep all the mass inside the house. The closer the collector is to the space, the better.
You might be over thinking this.
For one the mass should be in the house and you want your solar collector to be as light as possible so it gets hot fast.
Maybe some 4x4 posts, a sheet of insulation, hoops covered in a double layer of plastic or green house plastic, the nicer flex duct work, a thermostat or two and a fan. Air leaks could be a bad thing here as it would pressurize or pull a vacuum on the house this thing is attached to.
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