/sci/ - Science & Math

>>10151163
Don't bring tires onto your property. They are toxic as fuck and leach heavy metals into your local water table. If you are thinking of, "earthship," do not ever build one. There are many other better in-ground and partially in-ground building methods that accomplish the same thing for less labor and no trash. Earthship is synonymous with, "landfill."

>>10151071
Yeah, there's so much that can be done with passive solar, it is pretty amazing actually.

For thermal storage though, most people use a roof mounted evacuated tubes to collect the heat, pump it to a basement, and store it in a huge container of water. The loop for the roof is filled with antifreeze to prevent winter breakage. That's an active system since there's an electric pump involved. Systems that are fully passive are usually two story structures or places that have a sloped hill below the structure. That way they can take advantage of thermosiphon flow and never need a pump (pic). Designing a thermosiphon system can be difficult & costly because you need to maximize flow and reduce drag. Basically, you just use the largest diameter pipes you can afford for the external loop and have as few elbows & bends as possible. Those favor straight runs instead of zig-zags or coils that pumped systems can use.

In places where there's no freeze dangers, the thermal mass is stored on the roof with the evacuated tubes. The water line itself runs to the roof and no secondary heat exchanger using antifreeze is required. The normal water pressure from the water main takes care of the pumping action as it is used.

>>8932614
>>8932560
It is exceedingly simple and not very expensive. There are many applications. Check out "solar evacuated tubes" for the store-bought stuff. Lots of people do diy stuff, but usually not when it comes to energy for some reason. Parts for something like this image are really cheap or even free if you have a salvage source. You just need to have the skills and tools to do it.

The only passive solar wiki I know of is the one for solar cooking:

http://solarcooking.wikia.com/

There does need to be more of this stuff online in wiki form.

http://www.appropedia.org/Category:Passive_solar
http://www.appropedia.org/Passive_solar_design
https://en.wikipedia.org/wiki/Solar_chimney
https://en.wikipedia.org/wiki/Passive_solar_building_design

Here's one I designed about 2 years ago. This one uses copper in the heat exchangers and the one in the sun is enclosed in a insulated box with 2 panes of glass. The tubing uses water with anti-freeze so it can be left out in the winter without freezing. Check valves keep the pressure from getting to high.

It doesn't need a pump and uses thermosiphon design with 1-2 inch diameter lines instead.