Can I create a cheap but effective solar hot water heater for bathing using my south-facing bathroom window?

Image by USDAgov
Tonoho O’odham Community College occupational technology students receive hands-on training using solar demo trailer that is used to demonstrate different ways that solar energy can be used, including a passive solar hot water heater as shown on the roof of the trailer. The solar demo trailer is a mobile educational resource that is used throughout the schools and communities of the Tohono O’odham Nation in Arizona.

Question by joe friday’s grrl: Can I create a cheap but effective solar hot water heater for bathing using my south-facing bathroom window?
I moved into an older brick bungalow recently. We have just one bathroom, with a south-facing window (original glass) that’s about 2-1/2′ wide by 3-1/2′. The window is above the toilet, which sits right next to the soaking tub. I’ve never attempted to construct anything more complex than a small cardboard box solar cooker, and I don’t have much to spend on this project. But I’d like to try and construct a simple, insulated collector/holding tank in the window, which can extend beyond the window area itself in all directions only a couple of feet. But I do also have a wide linen closet on the other side of the toliet that has extra space for storage, if needed. I just want to heat enough water for daily bathing for a family of three. It could be as rudimentary as something I fill with water from a hose, and then have a way for it to flow down into the tub once heated. Any ideas, or is this something I need a more high-tech solution or more space for?

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