Matthew Nistico wrote:
@ Walter Jeffries - Walter, I find your concept of a lunar panel fascinating. Very creative. But I am confused about something: what about your system do you feel is an advantage over a classic passive solar cooling ventilation scheme? Have you done a study on the thermodynamics that suggests it is worth the extra cost and trouble? I'd really like to know. Like you, I am fascinated by the simple elegance of passive systems.
To elaborate my question... You are proposing a fluid loop powered by thermosiphon effect that transfers heat collected from the living space (via a radiator-type fixture, I presume) to a panel, from where the heat is radiated to the outside. So that requires two heat exchange fixtures (one inside, one on the roof), plus fluid, plus piping. Whereas at night (or whenever it is cooler outside than inside), I instead open my clerestory windows and my lower room windows and let the hot air exhaust from my house, drawing a steady flow of cooler air in at the ground level. This also works on a thermosiphon effect, but my heat transfer fluid is just air, and my heat exchange fixtures are just open windows (one high, one low). Yours is a closed loop system, whereas mine continually exhausts the cooling fluid. But then air is free. Clearly my system is simpler, lower cost, and more foolproof since there is no apparatus to require maintenance. But that doesn't necessarily mean it is more effective. Also, if one didn't build a clerestory into one's home, an exhaust fan would be needed instead, which then introduces an apparatus to break down as well as electricity to burn.
Interested in your opinion. Thanks!
Walter Jeffries wrote:
Tyler Ludens wrote:
Walter Jeffries wrote:
Lunar cooling panels
Do you have any links or other information about this?
Unfortunately no, I don't have a link because I haven't written the article about it yet. I invented them. The idea is simple though so let me give you the short version: A lunar panel is the opposite of a solar panel. With a solar panel you capture the light of the sun and turn it into heat energy which you then pump into a storage vessel. Rewind. With a lunar panel you take the heat from a vessel and run the fluid up through the panel pointed at the darkest part of the night sky (not actually the moon) and the heat radiates away. The now cooled fluid is denser so it falls back down into the vessel (your house, concrete slab, water tank, etc) and picks up its next load of heat. Once it is warmed it rises back up through the up side of the tubing to the lunar panel where it once again releases it's load of heat. Presto: Lunar Cooling Panels. I like passive systems that use thermosiphons so it has no motor burning energy but you could build it with a motorized pump if you were upside down (e.g., you were sending the heat down into a pond or the ground.)