Dale's Water Filled, Mobile, Trombe Wall- Hot Water Heater.
I've always been amazed at how complicated, expensive and prone to break down and weathering many solar water heating contraptions are. As someone who has heated many containers of water in diverse locations, I know that all that is needed is a dark coloured vessel with the side opposite the sun insulated, placed in a sunny location. If you can also locate it out of the wind,it will heat faster and achieve a higher final temperature. Placed indoors, it absorbs unwanted summer heat. -------------------------------------------------------------------------------------------------------------
This adaptation of 17th century technology is meant to be used in any situation where south facing glazing allows more light and heat than is desired, into your space during part of the day. Usually this situation is dealt with by installing exterior blinds (quite effective in summer but blocks heat gain if used in winter) or putting up curtains (blocks the light but the sun heats the curtains and heats the room,which is acceptable in winter).
My proposal blocks virtually all incoming light with a black, water filled solar panel, similar to the rigid type used to heat swimming pools. Picture a water vessel shaped like a slice of bread stood on edge, with a broad base so it doesn't tip over. It is on wheels and is rolled into position when needed. It would be attached to a base 18 to 24 inches wide and matching the width of the panel. The base contains a steel vessel that holds just a little more water than the collector panel. A hand operated pump raises the water into the upper plate collector. The top of this collector has a clear drain hose which returns excess water to the lower insulated tank. Since the system is open to the atmosphere, expansion or steam explosion could never occur.
WEIGHT
A 10 gallon system will weigh around 675 lbs. About 75 lb. For the heater and 600 lbs. for the water.
APPEARENCE
The back of the device is insulated and could be painted to match the room or covered in art posters....
Weight down low is good. Planters could be placed on the base with heat lovers on the sunny side and shade lovers in the shade. This marvel of engineering might look just fine as a bare bones specimen.
DAILY OPPERATION
Whenever overheating of the space is likely, roll the device into position. Ensure that the drain down spigot is closed, then pump the water up into the collector until a little flows back down the clear overflow tube. The collector will do its job all day. At the end of the day, it could simply be left to slowly radiate the stored heat back into the space. Usually the space will not need more heat in late afternoon. Drain the system into the lower, insulated tank. Late in the evening this stored heat could be used either by the window or it could be rolled to wherever people are gathered. In my situation, that might be onto an outdoor patio during summer or it could be left in place by open windows when stored heat is undesirable. The heat flows out the window over night. Drain down to lower tank before moving since the device could easily tip over when there is so much weight up high.
Hot water for domestic use could be drawn off, but it would be necessary to use caution since it could be at scalding temperatures. Then there's the issue of legionella bacteria. These bacteria can build up over time in systems that never get hot enough to kill them. If the water is used up every night and new water is added, there's no problem. If the system were used for several days at moderate temperatures without a water change, bacteria could build up. The usual path of infection is through inhalation while showering. Even stale water would be fine for scrubbing the floors. Most systems will experience a temperature spike by mid afternoon which is high enough to kill most life forms. There would be no point in employing the device on cloudy days. ----------------------------------------------------------------------------------------------
I won't be building one of these right away, but it is on a long to-do list. This is how I see using roof mounted systems for both hot water and air conditioning - Batch system solar hot water heater converts to air-conditioner https://permies.com/t/9820/solar/Batch-system-solar-hot-water
