Hybrid Car – More Fun with Less Gas

[M] Redefining personal energy security - Page 4

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Posted by Jim Wilkins on April 2, 2019, 3:01 pm
 
<ads> wrote in message  

No such luck here, Craig's List is dry and the local electronic  
surplus store has a waiting list for large AGM batteries. NH is both  
relatively rural and very high tech.


I've held that and other medical technician jobs. Government aid and  
heavy regulation significantly distort that industry beyond what  
appears logical. Look at the cost of EpiPens or an ambulance trip.
https://www.consumerreports.org/drug-prices/epipen-alternative-that-costs-just-10-dollars/  
https://www.usatoday.com/story/money/personalfinance/2017/05/20/ambulance-health-care-services-costs/334338001/  


I got ten years from the truck's OEM battery and 17 from the  
replacement that I took better care of, until its current into a  
Harbor Freight carbon pile tester dropped too close to the starter's  
winter demand. The OEM battery from my 2000 car still tests at 50A. I  
top off my battery collection about monthly with the solar system and  
a metered adjustable LM350 regulator I built.

Keeping old vehicles runs in the family. The last time I visited  
relatives in Alabama one still drove a 1935 pickup.

My garden tractor's battery is an Autozone Duralast U1 dated 10/13  
that a neighbor bought and gave me a few years later when it wouldn't  
start his mower in the spring. I added it into the monthly top off  
program and yesterday it still started my tractor. It appears that  
once they have gone flat they can be restored with higher DC voltage  
but need frequent recharging, which the friends who give me old  
batteries don't want to bother with.

AFAIK DC works as well as pulse desulfators, but requires more user  
knowledge and attention and a metered variable lab power supply (or  
homebrew). I learned how as the battery tech at Segway.

Old 12V 18AH AGMs, the largest I can usually find, don't last nearly  
as long with the same treatment. Some Powersonics still had 1/4 ~ 1/2  
capacity after 10 years, others have failed by sulfation or a dead  
cell in 5 or less, and 16~20V desulfation doesn't help them.



Posted by Jim Wilkins on March 31, 2019, 3:45 pm
 
<ads> wrote in message  

My new 4.3 cubic foot Magic Chef dissipates heat through the shell  
like that, so I can't add insulation. However a KAWez recorded its  
electricity cost this winter as only $.70 per month, at $.182 per  
KWH.




Posted by ads on April 1, 2019, 6:20 am
 On Sun, 31 Mar 2019 11:45:03 -0400, "Jim Wilkins"


I have a 4.4 cu ft Kenmore 99783 "dorm fridge" runs at 55 watts for
about 5.4 hours a day at 78F or about 330WH/day.  At $.0768/KWh, that
works out to about $.76/month so the performance of the two fridges
is similar (9.9KWh/month for mine, 9.3KWh for yours).  The small
fridge is my place to keep heirloom seeds - and the backup fridge for
leftovers when we have family here for holidays (Thanksgiving,
Christmas).  In a long term grid outage, it would be the primary
fridge after things from the larger fridge and freezer were used up.

Posted by Johnny B Good on April 2, 2019, 2:47 pm
 On Sat, 30 Mar 2019 08:12:55 -0500, ads wrote:

====snip====


 If you're trying to describe the flat topped peaks[1], typical of  
utility power worldwide, that's just the result of all the countless  
smpsus used in TV sets and desktop computers and USB wallwart chargers  
and laptop charging bricks and... well, let's just say there's a hell of  
a lot of mains powered kit that rectifies the mains supply to generate  
whatever dc voltages are needed (whether it be directly at full mains  
voltage or on the low voltage secondary of a stepdown isolating  
transformer such as an old school battery charger.

 Yes folks! Even ancient 70 year old battery chargers assaulted the mains  
supply with narrow conduction angle rectified current pulses which causes  
this 'flat topping' effect. It was just that, back in the day, such loads  
were in the minority.

 This flat topped appearance of the mains supply waveform has been  
present on utility supplies for well over three decades to my knowledge  
and probably existed to a lesser degree ever since the whole world and  
their dog started watching TV as a national pastime.

 The advent of the home computer and subsequent electronic gadgetry has  
no doubt exacerbated this situation to the point where this "Signature  
wave trace" can now be relied upon to identify when you're running off  
utility power rather than from a UPS or standby generator source.

[1] You may notice a downward slope on the 'flat tops' on the positive  
peaks of each cycle of mains voltage and mirrored in the negative peaks.  
This is the high pass filtering effect when using the AC coupling option  
on a 'scope or else seen in audio recordings made from a low voltage  
mains transformer winding (6.3v heater voltage winding attenuated down to  
the hundred millivolt level to avoid overloading your sound card's line  
input buffer, for example).

 Selecting DC coupled, will reveal the true wave shape, an option I  
didn't have with my 5MHz BW boat anchor CRO nor with my CoolEdit Pro  
recordings of mains voltage supplied by my generator and pure sine wave  
UPS to compare against the utility supply, until I finally treated myself  
to a brand new DSO some five months ago.

--  
Johnny B Good

Posted by Jim Wilkins on April 2, 2019, 3:22 pm
 
There are also spikes from SCR and Triac switching which can be  
anywhere including near the zero crossings. I had trouble with them on  
industrial park electricity when trying to construct a low phase noise  
line-synched PLL reference oscillator.



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