Maxwell's venetian blind

[HLHJ]

Uses a temperature differential to open/close a blind, which may also be infra-red reflective. Possibly the same principle can be applied to a vent.

People with passive solar heating and really insulating blinds can shatter their windows if they don't open the blinds early enough; this device would let people sleep in.

[rickj]

This is already out there. Have a look at http://www.motorizedblinds.co.uk/electr ... an-blinds/ for example.

[HLHJ]

I'm sorry, the website you linked to isn't at all what I wanted. These are just electric-powered blinds: "we offer you the automatic ones, using a remote control system that allows you to adjust them by just pressing a button." I can't imagine being too lazy to pull on a cord to turn the blinds, but I guess if you were bedridden this could be really useful.

What I was suggesting was blinds that adjust themselves to the ambient conditions (with manual override).

Firstly, if the temperature difference got dangerously big, the blinds would automatically open to protect the windows. The device would need to be cheaper than replacing the windows a couple of times. It would be nice if it was powered by the temperature differential, at least the deluxe version, because you'd hate to lose your windows because you're off-grid and the power was down.

The device might also be programmed by the user with an algorithm designed to keep the house at a good temperature (something like "close down half-an-hour before sunset, open when the outside temperature reaches X, close if the outside temperature reaches Y or the inside temperature exceeds Z. If the house temperature is above W at sunset, open the blinds until it falls to V"). Designed into a good user interface, of course; maybe just set a target temperature, like a programmable thermostat, and let the device learn how to achieve it.

See the penultimate question on this solar heating page, the one that begins "Q: I am in the late planning stages of a passive solar home in Calgary, AB, Canada".

[Chris]

Venetian blinds make our home very beautiful. These are available in different styles and colours. The hardwood slat venetian blind is exactly what you need. These splendid blinds have the nice look of luxury that only hardwood can bring to the windows. *url deleted by moderator*

[vishloff]

Green houses have temperature based pneumatic window openers. This mechanism would work for a venetian blind style window covering. Or as a trigger for another opening mechanism.

[Chris]

The cost of replacing the window in a cold climate is likely to be higher than in a warm to hot climates. The window would then be at least double glazed. Some are even triple glazed and sealed with inert gas between the panes. In addition, a building which is aiming for solar gain (at least some of the time) is likely to have large windows.

[vastonsmith]

The device might also be programmed by the user with an algorithm designed to keep the house at a good temperature (something like "close down half-an-hour before sunset, open when the outside temperature reaches X, close if the outside temperature reaches Y or the inside temperature exceeds Z. If the house temperature is above W at sunset, open the blinds until it falls to V"). Designed into a good user interface, of course; maybe just set a target temperature, like a programmable thermostat, and let the device learn how to achieve it.

[RubyLancaster]

Hi friend chris. It is not necessary that the building gaining solar power should have large windows. The building must have the space to place solar grid and the grid should be in proper place. The panel grid should be placed in such a way that sun light falls directly on the top of it. Silicon crystal panel is more effective.

[Chris]

Hi "Ruby", that is certainly one possibility, but not what we are discussing here. There are even combination PV panels which also contribute heat. I deleted your link as it is just a front for an obvious retailer. Thanks anyway,