Hoo pig, Soooeee! My family hails from NW Arkansas.
bob allen wrote: >I live in Arkansas,US of A, so it is the third world, except we have a >"nucular" reactor. > >Tom Irwin wrote:> Hi Bob,> > You mean people heating their water with >electricity aren't using flow > limiting shower heads. Why I'm shocked to hear >this. You must be talking > about people who live in the third world not the >first. Whew, I was > really worried there for a minute. But wait I'm confused, >most people > living in developing countries don't have accress to electricity >to heat > their hot water. What's going on here.> > Tom Irwin> > > >------------------------------------------------------------------------> >*From:* bob allen [mailto:[EMAIL PROTECTED]> *To:* >Biofuel@sustainablelists.org> *Sent:* Fri, 14 Oct 2005 09:53:14 -0300> >*Subject:* Re: [Biofuel] Grey water heat recovery and low tech Solar> >collectors????> > Although my observations will offset in terms of net >effects, a fifteen> minute shower is a really really long shower in my >experience. A few> years ago I had students go out and calculate energy >use for showers.> average length 3 to 4 minutes, temperature around 40 C, >and flow rate> varied from 2 to 6 gallons per minute, average on the high >end about 5> gal/min. this from a combination of dorms, apartments, and >single> family homes.> > > > > > Tom Irwin wrote:> > Hi Mike,> > >> > Lets do a quick calc. Let's say flow is a gallon a minute for 15> > > minutes. Let's say you like really hot showers at about 45C.> Let's >say> > room temp is 20C giving us a differential of 25C. Mass x >Temperature> > change x specific heat.........> > hmmmmm less than >6000 kilojoules. Yep, ridiculous, meaning I> wouldn't> > waste may >time or capital. Of course, I didn't really consider> leaving> > the >water in the bathtub. That will heat ya twice, once from the> waste> >> heat and again when you scrub the tub.> >> > Tom Irwin> >> > >> >> >------------------------------------------------------------------------> >> *From:* Michael Redler [mailto:[EMAIL PROTECTED]> ><javascript:kh6k0("new","[EMAIL PROTECTED]")>]> > *To:* >Biofuel@sustainablelists.org> ><javascript:kh6k0("new","Biofuel@sustainablelists.org")>> > *Sent:* Thu, >13 Oct 2005 10:31:05 -0300> > *Subject:* Re: [Biofuel] Grey water heat >recovery and low tech Solar> > collectors????> >> > With all >due respect Tom, when I see someone use the word> > "ridiculous" in >threads like this, I usually think of the people who> > actually believe >that the buck stops with them, every possible> > scenario has been >explored and all possible conclusions made as to> > the potential of an >idea (even if you put "seems" in front of it).> > It is presumptuous and >discounts contributions made by people like> > John who present and >argument and back it up with something other> > than conjecture.> >> > > Although, I'm not convinced that the concept can work effectively, I> > > think of the variables involved, like the energy necessary to heat> >> the water from ambient, the amount of water being heated and the> > >difference in temperature.> >> > "...bacteria that will definitely >grow and clog heat exchange> tubing."> >> > Fouling is a >foregone conclusion in most heat exchanger applications> > and If >clogging from bacteria were that severe, I suspect that most> > people >would be taking baths, whether they want to or not.> >> > >"...problems in trying to recover shower water at 40 or 45 C"> >> > >Air conditioners are expected to function in similar situations. One> > >thing about using heat pumps for generating heat is that> > inefficiency >in the cycle is not necessarily a bad thing. After all,> > you are trying >to generate heat. This is not a new idea. Below is an> > article from >www.motherearthnews.com> > which talks about applying it to> > solar >and geothermal systems. In addition, I know that it is used to> > recover >heat from attics for domestic hot water. I think that heat> > recovery >from waste water might also be an appropriate application.> >> > >"Though solar energy is likely to be one of the most popular heat> > >sources for the new absorption-cycle heat pump, the design is> > equally >well suited to cogeneration systems using waste heat or> > geothermal >heat sources."> >> > *http://tinyurl.com/dxk4p> >> > >*Mike> >> >> > */Tom Irwin> > >/* wrote:> >> > >Hi John,> >> >> > Just because graywater has some heat in it >does not make it> > economically recoverable. Graywater is a wonderful >breeding> > ground for fungi and bacteria that will definitely grow and >clog> > heat exchange tubing. I think it will be a huge headache and a> > > waste of capital and time. Think about the problems in trying to> > >recover shower water at 40 or 45 C for a 10 or 15 minute> > period. >That´s only a 20 or 25 C differential for a very small> > amount of time. >It seems ridiculous to me.> >> > Tom Irwin> >> >> >> > >> >------------------------------------------------------------------------> >> *From:* John Hall [mailto:[EMAIL PROTECTED]> ><javascript:kh6k0("new","[EMAIL PROTECTED]")>> > ]> > *To:* >Biofuel@sustainablelists.org> ><javascript:kh6k0("new","Biofuel@sustainablelists.org")>> >> > >*Sent:* Wed, 12 Oct 2005 23:16:44 -0300> > *Subject:* Re: [Biofuel] Grey >water heat recovery and low tech> > Solar collectors????> >> > >Jim,> > There are commercial grey water heat recovery systems out there.> > > They> > recover 50% to 75% of the heat going down your drain, >largely> > while taking> > showers. According to the DOE studies >conducted. Check> > http://www.gfxtechnology.com/> > There is one >other company that makes a similar product for> > about the same> > >price of $375 and there are tax incentives for these.> >> > I do not >agree that they would not be worth it for the money> > since most> > >homes use about 30% of their energy bill heating water. This> > should >cut> > that about in half.> >> > Regards;> > John> >> > >> >> >> >> >> >------------------------------------------------------------------------> >>> > _______________________________________________> > Biofuel >mailing list> > Biofuel@sustainablelists.org> ><javascript:kh6k0("new","Biofuel@sustainablelists.org")>> >> >http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org> > >> > Biofuel at Journey to Forever:> > >http://journeytoforever.org/biofuel.html> >> > Search the combined >Biofuel and Biofuels-biz list archives> (50,000 messages):> > >http://www.mail-archive.com/biofuel@sustainablelists.org/> >> > > -- >> Bob Allen> http://ozarker.org/bob> > "Science is what we have >learned about how to keep> from fooling ourselves" — Richard Feynman> > > _______________________________________________> Biofuel mailing list> > Biofuel@sustainablelists.org> ><javascript:kh6k0("new","Biofuel@sustainablelists.org")>> >http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org> > > Biofuel at Journey to Forever:> >http://journeytoforever.org/biofuel.html> > Search the combined Biofuel >and Biofuels-biz list archives (50,000> messages):> >http://www.mail-archive.com/biofuel@sustainablelists.org/> > > > > > >------------------------------------------------------------------------> > >_______________________________________________> Biofuel mailing list> >Biofuel@sustainablelists.org> >http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org> > >Biofuel at Journey to Forever:> http://journeytoforever.org/biofuel.html> > >Search the combined Biofuel and Biofuels-biz list archives (50,000 messages):> >http://www.mail-archive.com/biofuel@sustainablelists.org/> > >-- Bob Allenhttp://ozarker.org/bob >"Science is what we have learned about how to keepfrom fooling ourselves" — >Richard Feynman >_______________________________________________Biofuel mailing [EMAIL >PROTECTED]://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org >Biofuel at Journey to Forever:http://journeytoforever.org/biofuel.html >Search the combined Biofuel and Biofuels-biz list archives (50,000 >messages):http://www.mail-archive.com/biofuel@sustainablelists.org/ > > _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
