Xref: utzoo misc.rural:1817 sci.electronics:18503 Path: utzoo!news-server.csri.toronto.edu!rutgers!bionet!uwm.edu!linac!att!pacbell.com!lll-winken!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!csn!boulder!tramp.Colorado.EDU!gordon From: gordon@news.colorado.edu (GORDON ALLEN R) Newsgroups: ba.mountain-folk,misc.rural,sci.electronics Subject: Re: Wanted: info on self-contained power systems for houses Keywords: generator, photovoltaic, battery Message-ID: Date: 13 Mar 91 20:55:55 GMT References: <445@octelb.octel.UUCP> Sender: news@colorado.edu (The Daily Planet) Reply-To: gordon@tramp.Colorado.EDU Distribution: na Organization: University of Colorado, Boulder Lines: 77 Nntp-Posting-Host: tramp.colorado.edu jfd@octel.UUCP (John F. Detke) writes: >Hello, >I am activly pursuing purchasing a house beyond PG&E power. >The house currently has a 5 KW generator, batterys and >a 24 volt converter, and propane refridgerators. >I am interested in starting a discussion, and getting >any experience with such systems. Items I am particularly >interested in are: maintenance requirement, battery life, >generator life, etc. I know most of these are "it depends". >Additionally, Bay area or mail-order supply for this equipment >and propane appliances would be appreciated. >My primary concern is my home computer (Sun 3/60 w/ 141 Disk drive) >I was planning on adding a UPS, but am unsure how this constant drain >will affect the system. >The house has a fairly good southern exposure (or rather, >the land does) so photovoltaic cells may be possible as an addition. >So, the big question: Are home computers completely incompatible with >self-generated power systems? >Also: if anyone has ANY info on the costs/possiblity of paying for PG&E >extensions, I would be interested (I am pretty sure this is not very >cost-effective :) >Thanks, >jfd >-- >John F. Detke >Octel Communications Corp >890 Tasman Drive >M/S 05-04 >Milpitas CA 95035 >jfd@octel.com I've been consulting on a project to develop the hydro and pv resources on a site in a remote area of New Mexico about 8 miles from the grid. The estimated cost of hookup to the grid is $200,000. We can probably do a lot with the existing resources with far less money. Aside from the hydro, it seems there are a lot of similarities between our two systems. Things to consider are proper sizing of the batteries to both the pv panels and the generator as well as to the loads, in order to get optimal charging and discharging cycles. This will not only prolong the battery life but give you optimal state of charge as well. We have recently switched to NiCd batteries (vented, pocket plate). They can be had 2nd hand, although they are still more expensive that Pb-acid types. However, their life span is longer, they can be reasonably easily reconditioned, can be floated/trickle charged. I would second the suggestion of switching to a '386 portable because of the power considerations. With a battery pack, you have a built in UPS system making the system virtually immune from power fluctuations, etc. Such problems (brown outs/black outs) killed one of our computers. You also might look into Sunfrost or Photocomm refrigerators instead of the propane. These run at about 10% of the power consumed by convential units and could withstand a black out for probably quite some time with only minimal temp rise. Look into compact fluourescent lighting, another big energy saver (about 25% of the conventional incandescents). Good luck Allen Gordon -- Allen Gordon University of Colorado, Boulder gordon@tramp.colorado.edu gordon_A@cubldr.colorado.edu