Pv for s/h/w..... [RE-wrenches]

[sunwise at cheqnet.net]

Original Message:Tom Lane

Don't use PV power to heat hot water or Einstein will roll over in his
grave.

Hey Tom,

I have always agreed with you on this.  But... something got me thinking.  If a tempering tank was used, plumbed in as a pre-heat to the existing H2O heater, and a low voltage, low wattage DC heating element installed (use a cheap glass-lined electric heater for this T-tank), and something on the order of a couple hundred watts of PV wired in??

If, like most folks, they were gone for the daylight hours or otherwise not using much hot water then, that little bit of PV could heat up 50 gallons of water during a sunny day.  It doesn't have to get it real hot, but if it did, a thermostat already exists on the electric H2O heater.  Any heat going in is saving BTU's on the fossil fuel end (just installing an un-insulated tempering tank will "pre-heat" some water).

SDHW systems using flat-plate collectors and a closed-loop antifreeze system are expensive and labor intensive to install  They are much more efficient at heating water, but if the water gets used at night or early morning, they aren't offering any more hot water than that existing in the T-tank anyway AND they are a lot more expensive to install with more maint. and shorter operating life.

Plus!, a small PV system like this could offer a little back-up electrical power in the event of a power outage if creatively wired.

Smitty, Wha-da-ya think??

Kurt Nelson

--------------------------------------------------------------------
mail2web - Check your email from the web at
http://mail2web.com/ .

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://www.topica.com/lists/RE-wrenches/

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

==^================================================================
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9
Or send an email to: RE-wrenches-unsubscribe at topica.com

T O P I C A -- Register now to manage your mail!
http://www.topica.com/partner/tag02/register
==^================================================================