Pressure to Heat Conversion for Bathroom Water Heating

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One would need a colossal amount of mains water to do any significant heating and a storage vessel the insulation of which far out-performs anything available today. The economic analysis of such a proposal would easily indicate that conventional heating methods are preferable.

From the extraction site to your home, the water undergoes much more friction than you can probably apply to it at your bathroom, and still chills the heck out of your bare back.

The ammount of energy attainable by such a very little flow, as you will have passing thru your insulated container, is simply not enough to make a sensible difference in the water temperature, not even a single Celsius degree.

Don't get dazzled by the pressure, it is the flow wich can be converted to mechanical energy, and then to whatever you want, but of course you need to have pressure in order to start a flow.

Abort any purchase of stuff, you'll pitch your money to the trashcan. Use your cash to do some research, buy a book or two, pay your I.S.P. for spending many hours surffing the web in search of trusty information.

Stablish your priorities: "is it learning, or simply hot water what I'm interested on ?" because you could just buy a new heater ( I'm going to do that myself, and soon !).

Agreed, the complexity and payback period is ridiculously low compared to other 'green' standalone alternatives for heating water.

You just need a way to get that many people into the shower....Free beer ???

...which boils down to hydraulic power being less effective than other forms of transmission.

GA, BTW.

Basically to take one shower you would need to move the volume of a typical motel swimming pool.

... and pay the water usage and sewage disposal charges, incur the wrath of your neighbors for lowering the local water pressure, pay for the installation of waste water lines large enough to handle the flow, etc. If they can put a man on the moon...

But hey, amortize the capital cost and refine the system a little, and you could get your cost per shower down to maybe less that $100.

GA, by the way.

If your interest is sincere and your goal is to produce hot water for bathing i have a solution. It's not available for free however. I will sell you a complete working system scaled to your requested volume of production/storage. This does not use "friction" or any other commonly understood method. No electricity in any significant amount is needed, nor is gas used. Solar is an excellent augmentation, but is not essential. A complete system to deliver hot water for the average bathroom would cost around $3k But, you would only use about 20 cents a day in electricity! If you can get 2AHD of PV where you are, the the cost would be zero! (The PV system will add around $300 to purchase price.) Contact me by direct here if interested!

sounds like a ~10KW tank-less, on-demand, electric water heater... but I may be wrong

In nature nothing is free and although the water arrives under pressure the gain in heat would be minimal- the only way to use friction would be to so significantly increase pressure that the cost would offset any heat gain- use solar panels or a heat pump if your really want to play genius

The fundamental physics problem with your idea is that pressure does not convert into heat. Pressure and flow, taken together, can do work, and therefore can convert to heat. At 4 Bar pressure, you would need to use an astronomically high amount of flow to heat a very small amount of water. The power available from ordinary shower flow is on the order of a few hundredths of a watt, and you need about 15 kilowatts to heat water to feed one shower head. (http://www.ecosmartus.com/products/electric-tankless/eco-8-eco-11.aspx )

I tend to think in English units, and have (automatically) memorized some formulas that keep showing up in my work. 15kW is about 20 HP. Hydraulic HP is (in English units) PSI x GPM / 1714. So at 60 psi, you'd need about 250 GPM to produce the required heat, if your heater were 100% efficient in transferring that heat to the shower water. 250 GPM is the flow through about 125 shower heads.