XPost: talk.politics.guns, sci.energy   
   From: muratlanne@gmail.com   
      
   "Scout"  wrote in message news:siv7tl$t50$7@dont-email.me...   
   "Jim Wilkins"  wrote in message   
   news:sitfja$nb7$1@dont-email.me...   
   > "Just Wondering"  wrote in message news:Ssq4J.17545$IO1.13914@fx19.iad...   
   >   
   > On 9/27/2021 2:15 PM, Dechucka wrote:   
   >> On 28/09/2021 5:57 am, contact wrote:   
   >>> When the wind stops blowing, the electricity stops flowing!   
   >>   
   >> Interesting my house is totally solar and I have power at night. Go   
   >> figure   
   >   
   > We all figure that either "my house is totally solar" or "I have   
   > power at night" is a lie, because they can't both be true.   
   >   
   > -----------------------   
   >   
   > "Totally solar" is a "black box" model which means that solar is your only   
   > source of electricity, it can include storage batteries to postpone the   
   > use of that electricity.   
   >   
   > https://en.wikipedia.org/wiki/Black_box   
      
   Average consumption 30 kilowatthours (kWh).   
      
   Figure 16 hours of storage as a bare minimum   
      
   100Ahr battery = 600 wh   
      
   Minimum required 40 batteries.   
      
   Cost about $8000 just for the batteries.   
      
   Another $14,000 for the solar system   
      
   Figure about $15,000 for installation.   
      
   More for the lost floor space, or building to hold all this.   
      
   And that only gets you through the day. If you don't have 8 hours of full   
   charge... overcast, raining, snow, etc then your battery capacity   
   requirements will go up drastically,.   
      
   Then we need to calculate the pollution produced for all that hardware, the   
   regular replacement of the batteries, panels and systems over a lifetime and   
   then figure out if you're actually cutting emissions... or just spreading it   
   around.   
      
   Seems to me to be a lot of money and issues for a dubious reduction in   
   pollution.   
      
   --------------------------   
      
   My backup system isn't nearly that large or expensive, and my normal   
   consumption is under 5KWH per day.   
      
   The backup supports a compact refrigerator and small freezer plus one or two   
   laptops for cellular Internet and antenna television. For meals I run a 2KW   
   inverter generator, or use the wood stove since most long outages here are   
   from winter ice storms. Laundry requires a 3KW generator and kick-starting   
   by releasing the old Maytag's belt tension with my foot on the motor. I   
   freeze-dry the laundry on an outdoor clothes line, typically within the same   
   day since winter humidity is very low.   
      
   Two fairly new 12V 105Ah marine batteries will run the inverter for at least   
   24 hours and maybe 48 depending on conditions. The freezer operates on 12V   
   DC and can go almost 48 hours on the original pair of ~10 year old   
   batteries, by recent test. The four marine batteries and four 100W panels   
   averaged $100 apiece and the sine inverter was free, a "dead" high end APC   
   UPS. Installation is standing the panels on fold-out legs in the yard or   
   driveway when I need them for an outage, otherwise a row of small flea   
   market panels on the roof powers the freezer. After measuring power loss I   
   upgraded the house solar wire to 10 AWG, a significant expense if you buy it   
   new.   
      
   As best I can figure, the cost of battery depreciation if cycled daily   
   somewhat exceeds the cost of grid power, so I use the system only for backup   
   to prolong battery life. I ran the numbers for flooded, AGM and Lithium and   
   flooded won IF maintained, but not if neglected. I pay $0.18688 per grid KWH   
   and these $100 batteries would cost $0.20 per KWH if they delivered 1 KWH   
   each, 500 times. They probably wouldn't last that long, 500 cycles is   
   pushing the claimed performance of AGMs at twice the price and reportedly   
   half the storage life, so the high end estimate for battery cost ran around   
   $0.50/KWH, close to using a generator. I get nearly 10 years in storage from   
   used PowerSonic 12V 18A AGMs if they are topped up regularly, less than 3   
   years from Rhinos. They are considered dead and recycled when they won't run   
   the freezer the equivalent of overnight.   
      
   If I switched to daily cycling I would buy different batteries because the   
   flooded ones may gas if charged fast enough, meaning high enough voltage, to   
   fully recover from a deep discharge during winter daylight. They don't gas   
   if limited to the float voltage, but they also don't fully recharge in a   
   day. They do charge to 70~80% before reaching the gassing voltage, which is   
   enough for me.   
      
   Unless more trees die and fall I don't get enough sun on the roof to justify   
   a larger permanent installation. What I have has let me unplug from the grid   
   and keep operating as usual when thunderstorms threaten, and stay off it if   
   they last overnight. I've only needed the generator briefly a few times   
   during an extended winter blackout. In clear weather 400W (~330W into the   
   batteries) of solar power recharged the batteries into the acceptance   
   (declining current) range by 10AM.   
      
   -jsw   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)