On Sunday 15 April 2018 20:47:54 Chris Albertson wrote: > Yes, I have done this but not on a house. I used to own a sailboat. > > First off if you need to run AC you are going to need to fill your > garage with racks of batteries. > > Let's assume you have a smaller AC unit that only uses only 3,000 > watts dn you run it with a 50% duty cycle for 12 hours. That is 18KWH > per day. A good pair of high quality golf cart batteries will give > you 1.5KWH but that assumes you discharge them to full empty. They > will not last even one month if you do that. 50% discharge is the max > you should do. so that is 0.75KHZ. > > A good rule of thumb is to have on hand two days worth of battery > power. so you need 2 x (18 / 0.75) = 48 pairs of batteries (each is 6 > volts) Or lets just say 100. The Trojan T105 is a great battery for > the money. at $160 each. But the T125 will outlast if the about > $200 each. The battery farm will cost at least $16,000.00 and that is > with not chargers and inverters. > > Ok so maybe you don't need to run A/C. If yu just want to run a > fridge and some light bulbs and maybe a TV or laptop computer you > might do with a smaller battery farm. > > The BEST way to estimate the amount f power you need is to look at > your electric bill and then divide it by the number of days. Lets > say you don't have A/C and use only 4KWH per day. Then you need a > battery bank that can give ou t 8KWH and and discharge to 50%. You > need a nominal 16KWH bank. Using the T105 battery (lowest cost good > option) you would need 20 of them for about $3,200.00 > > To charge the batteries just figure how many hours the wind blows and > and de-rate you wind mill by 2X. if you need 4KWH per day as in the > last example above then 16 of your $500 wind mill will be enough. > That is about $8,000. On't forget the electronics. You might be > able to build it out for $20K but yu don't run A/C on a small system > like that. > > When I had the boats I could live with a LOT less power. No > refrigeration and just a few LED lights when at anchor. I had 6 of > the T125 batteries and one marine engine-start batteries for my 27HP > diesel 3 cylinder engine. The engine has a 20A alternator that could > supply up to 200W and it would take hours to do any charging. > > The biggest recurring cost when you go off grid is battery life a > 50% charge discharge charge gives you 125 AH of current but a T105 can > do this maybe 200 times before it is toast and they cost $160 each > So you have to pay $160 for 250,000 AH or 1.250 MWH Or about 12 > cents per KWH for power. You will NOT save much over what the power > company charges you. With today's technology you can about break even > > There ARE better batteries but you pay a lot more up front for them. > The T105 is the best deal in cents per KWH over the battery life time. > > What I am waiting for is for the market to be flooded with junk > electric cars. A a few years all cars will be electric and then 20 > years after that used batteries will be dirt cheap. No one wants a > battery inter car that can only change to 1/2 of its new capacity for > for your house having 10 oe 12 of those is a lot more then you need. > > Yes all cars will be electric. Much or Europe, the UK, China, > California and others already have a sales bad on new gas/diesel cars > to take effect in 10 to 20 years. > > One more thing. I was talking about Trojan T105 or T125. These ar 6 > volt batteries but you would likey want to wire these up as a 24 or > even36 or 48 volt DC system because it saves you ToN of money in > copper wire. A typical 12 volt system will use a lot of size 0 and > 00 welding cable but at 48V you are using ## or #4 Why? a 12 volt > system for can entire hour might be 1,000 amps going into the > inverter,
That puts it in a more practical light, the conclusion being that it might be practical in 20 years, but rather impractical ATM. But I won't be around in 20 years, maybe not even 5. So theres the answer, let the next owner do it. Thanks Chris. > On Sun, Apr 15, 2018 at 4:40 PM, Gene Heskett <ghesk...@shentel.net> wrote: > > Greetings all; > > > > I see Banggood has a 500 watt wind thingy for under $200 that net > > folks are calling professional grade stuff. I am looking to put up > > an anerometer to record the wind speeds, one of those 3 cups designs > > that isn't direction sensitive, and one of these card computers to > > log what it sees so as to get an idea who many of these 500 watt > > things I'd need to keep a bank of truck batteries topped up while > > running the house, including the AC. > > > > Has anyone else walked this trail, or do I have to start with a > > machete? > > > > -- > > Cheers, Gene Heskett > > -- > > "There are four boxes to be used in defense of liberty: > > soap, ballot, jury, and ammo. Please use in that order." > > -Ed Howdershelt (Author) > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > ------------------------------------------------------------ > > ------------------ > > Check out the vibrant tech community on one of the world's most > > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
