Anybody use reflective sheet to increase solar gain ?

[welshboy]

Does anybody use a  reflective sheet to increase solar gain ? If so what material/cost metre ? Thanks

[Mudman]

Hi
do you mean for PV, for tubes or simply to reflect more light into your windows? i've done the latter using aluminiumised plastic sheet but could not fix it strongly enough- fixings came loose. would do it using aluminium sheet if i found such an item lying around.

[welshboy]

I was thinking about solar thermal collectors but I suppose it could extend to your windows idea. It should be easy to make a sandwich of ply/ reflective sheet/perspex and screw it in place as and when required

[frotter]

I've used aluminium foil if thats any help..........

You have to scroll down a fair way, sorry.

http://www.navitron.org.uk/forum/index.php/topic,6069.105.html


 

[welshboy]

Cheers Frotter.
Was it the pva that you used to glue it to the wood and how is it faring in the weather ?

[rhys]

How about "Mylar" comes on perspex as a mirror or on a roll.

[welshboy]

Thanks Rhys- Mylar is much more reflective than Aluminium foil which seems worse than white paint from what I have read.

[djh]

Mylar is the flexible film, which is metallized to make it reflective. Mylar film is also used as the basis for many high-performance sails.

Mylar degrades when exposed to UV. For cruising sails it's covered with an additional 'taffeta' layer. Racing sails don't do this because it loses performance and so they have to be replaced every few years.

It'll take a while though so might still be useful if it's accessible to replace it - perhaps every 5-10 years.

[rhys]

I thought it was UV resistant.
http://www.doylesails.com/design/fiber.html
Anyway the stuff in my greenhouse has survived quite well - 8 years now.