Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
The Outhouse Powerwall
Progress continues. September has been a wet month, more so than August! But even with all that rain I managed to finally get the panels off the lawn and on a rack.

Gah! All that ground water!


September's output has been abysmal! I can't stand the constant dreary weather, nothing but overcast clouds and rain. I don't think I can hack it in the Pacific northwest!


Couple more interesting math:

                                                Estimated    Estimated
           Total PV kwh     Total AC Output    Idle Loss    90% Efficiency Loss

August         184.8kwh         132.7kwh          36kwh        14.8kwh

September      122.2kwh          74.9kwh          36kwh        8.6kwh

There was barely a few days of full sun the entire month. I couldn't believe how much cloudy days affected my output. There was only a few days when I reached full state of charge. The one thing caught me was my total AC output for the month of Sept was half that of August.

I spent some time calculating from the data and it looks like my AC output does match the math. I was assuming a 50watt loss on the PIP, so ends up 1.2kwh per day and 36kwh per month. Then I assumed the inverter was only inverting at 90% efficient, so a little more loss in it. Subtracting the total PV with the estimated values ended up very close to the actual AC output.
Redpacket and cowpen like this post
Today was my first day of breaking the 10kwh of solar power generation!!! I know this may not be much excitement for some of you   Tongue  BUT it's been over a month that I reached 10kwh of storage and since then there's NOTHING BUT clouds and rain and it has never fully charged on its own. Weather's been so terrible I think they said they haven't seen rain this much since '99 for the month of Sept.

So today was just perfect and with my recent ground mount install I broke my 10kwh mark! Smile

Hanssing, cowpen, Redpacket like this post
awesome project. love the grafana interface. really a good example how to do it right.
Congrats on the milestone!
Anfangen ist leicht, beharren eine Kunst.
Thanks for the encouragement!! It's all a work in progress!

I broke 10kwh again today with an awesome cloudless day! But more importantly I managed to get another milestone done!

Over the summer a friend of mine gave me a mini-split air conditioner with heat pump. It's a 12k BTU unit that ran on 120v! We finally installed it this week and it's been performing great! First of all it's an inverter type unit (like most mini-splits) and that means no hard start issues. It slowly ramps up and only runs as much as it needs, unlike window a/c units where it's just a hard start and running the compressor at 100%. So that means no need to worry about any huge surges and no flickering of lights. Also this is a 120v unit, which means it can run on my PIP. Now the next best part is that I currently run on electric baseboard, so a heat pump is much more efficient, so that's a lot of cost savings. Unfortunately this is a rather old unit, so the HSPF is only in the 7+ range. Peak is roughly at around 1500w. I believe newer units run in the HSPF 11-13 range. But no complaints here Smile


The inside blower units runs at its lowest settings at only around 20-30w. That's the idle power. I am keeping it at around 64F right now (outside temp around 50F) and it runs at around 250w to keep my apartment warm. Once it gets colder I'm sure it's going to be less efficient but I can't wait for the colder temps so I can see how efficient it is compared to electric baesboards.

Below you can see it jump from 200w to 400w, that's when the mini-split kicks in to maintain my temp. The rest is my regular usage (around 150w for my computers and electronics). I did take my fridge off it because I was afraid of both the defrost cycle of the fridge (600w) and the max a/c unit (1500w) kick in at the same time causing me to trip my breaker. It is only a 2400w inverter.

I'm now back to salvaging batteries, I have to add another 3 more rows of 18650s! It's an awesome winter thing to do and I've buckets of 18650 to process! Rolleyes
Redpacket, wim, jdeadman And 2 others like this post
Installed another solar charge controller last weekend! Didn't go as smoothly though. Broke both my BMS and my A/C unit that weekend too. Somehow blew up the comm port of my bms, think I had a bad power supply for the Pi and that blew the usb to ttl, which in turn blew up the bms side. So I'm out of that telemetry. Thankfully it's only $75 for another bms. Then after I installed the eSmart3 and put it all back together. Then later I found that something broke in my a/c split unit. Cost to replace the board was too much. Pity. So just ordered another split unit.

Anyways, I bought this eSmart3 60A on ebay for around $150 early during the summer, but never had the chance or need to install it. So just installed it for extra power during winter. Seems to be a decent unit so far. It doesn't react to MPPT tracking as fast as the PIP but I think it holds its own. I also managed to find information about the protocol through a website on the internet, then I contacted the mfg and they were kind enough to supply the full protocol spec. From there it was easy to build a python script to dump the data from the RS485 port and merge it into my influxdb for the PIP.

Below is the url link where I got the pinouts and the start on how to program the python script. In there he noted that while testing the MPPT would drop out and needs a manual restart. I have yet to experience that yet, but it could be that he didn't have enough panels to cover the voltage needed. Mine is put 3 in series for around 115V, so plenty of power to operate. I also have the full protocol spec, so if anyone wants it just let me know.

Below is today's output. It was a full day of sun on Sunday Angel   I set the eSmart3 to stop at 28.4V while the PIP would go up to 28.6V. Like the review said, there's a slight variation in voltage, mine was off the PIP by .2V. No biggie. From the graphs it looks like my batteries were fully charged by 12.30pm and the eSmart3 went on float while the PIP also started to back off. Couldn't break 12kWh, but got close to it! Had all my appliances running to keep the usage high hehe.

wim and Redpacket like this post
Just a quick winter update.

The Outhouse survived it's first sub-zero temps! Over this week it's been in the 0-10F (-17C to -10C) and the wind-chill was way below in the -5F and the Outhouse managed to stay warm the entire time.

From the graphs you see the mini spikes where the controller would kick in to power my small 200W ceramic heater. The one mistake was over the summer I bought a temp controller that could handle both cooling and heating, cooling to turn on the fan and heating to turn on the heater. It just couldn't handle the wide range so I ended up buying another temp controller just for heating.

The 200W heater did its job and maintained my batteries above 42F with plenty of room to spare if it needs to go below 0F.

My mini-split also worked well and it replaced my electric baseboard heating. I still need to wait until the entire winter is over to calculate the winter savings but safe to say it's cut my electric bill in half. I would have used 1000kwh easily and I've only used 300kwh for January's electric bill!

The eSmart3 solar charge controller has been working great as well. The one thing I noticed was that when I had 3x245w panels in series, it only output about 450w. I know my panels are used (80-90%) and not pointed in the right angle, but it seemed less efficient compared to my PIP. Reading the book it recommended to have them 2 in series for 24V setups. So I added another panel and switched to a 2 parallel x 2 series I got about 720W.

3*245w=735w.  Actual was 450w max. 61% efficient.
2*245w + 2*245w = 980w. Actual was 720W max. 73% efficient.

It's possible that for 24V it's better to have it configured in 2S instead of 3S. My panels are roughly 32Vmp so maybe the eSmart3 MPPT worked better in the 64V range than in the 96V range.

One big issue I have right now is that my PIP2424LV doesn't seem to want to switch from Grid to Battery when under heavy load. I'm talking about 800W when the mini-split is running. Once it drops below 500W it will then flip to grid. But on some cold days the mini-split will not take a break and I come home to see the battery 100% charged yet I'm still on utility. I then turn off the mini-split and the PIP immediately switches back to Battery mode. Not sure why that's happening!

Other than that, I just finished testing another 7S60P pack and just needs the busbars and ready to install! Should happen in the next two weeks!

Big Grin
Korishan likes this post
What kind of shunt are you using to gather the power stats?
(02-03-2019, 06:28 PM)mike Wrote: What kind of shunt are you using to gather the power stats?

No shunt, just straight logging from the PIP serial output.
mike likes this post
Finished my fourth row of batteries! Now up to 14kwh (roughly 8kwh usable)!  Big Grin I have space for two more rows to bring it up to a total of 21kwh, which would do nicely during winter months. I still have probably about 20-30kwh of batteries waiting to be harvested...

Also broke 1MWh of power generated! I would have broke it sooner but I didn't start recording until later in April or so of 2018 and then I lost some time when my inverter went down during the summer.

And today generated 15KWh! That's the most so far!

Next up is a Hot Water Pre-Heater!! Winter is almost settling down now so with more sun hours and less usage during summers means I will have the batteries at 100% early in the day time, so  I've got to come up with new ideas to use the excess power. The only 'power' I use is the natural gas water heater, so I'm going to install an electric pre-heater tank. Now deciding whether to go direct PV or through the AC. But that's going to be in a few months and I'll have some time to prepare.

Oz18650, ajw22, Korishan And 4 others like this post

Who read this thread?
100 User(s) read this thread:
hbpowerwall (07-25-2019, 04:00 AM), AZ_Tekkie (07-11-2019, 05:17 AM), daromer (02-03-2019, 06:36 PM), Sean (05-06-2019, 07:58 AM), mike (02-04-2019, 10:48 PM), station240 (11-01-2018, 09:45 AM), Joaquinsfy (10-14-2018, 07:32 PM), NiVa (10-09-2018, 07:06 PM), owitte (02-20-2018, 01:58 PM), opus40 (10-21-2018, 07:14 AM), VdVoort4 (09-06-2018, 06:48 AM), Majorphill (11-11-2018, 06:12 AM), Elwood (10-23-2018, 06:40 AM), ruby2 (01-20-2018, 08:21 PM), Korishan (05-06-2019, 05:40 AM), A + A (12-26-2017, 02:21 PM), PAF (05-11-2019, 04:13 PM), Franky Beuselinck (05-06-2019, 06:31 AM), Wattsup (02-03-2018, 12:35 AM), eeesOap (08-01-2018, 12:59 PM), Frnandu Martiński (12-30-2017, 11:07 PM), Mike C (08-01-2018, 07:08 AM), jdeadman (05-06-2019, 12:32 PM), charlie246 (01-08-2018, 10:11 AM), wim (05-06-2019, 06:47 AM), wimpie007 (02-04-2019, 10:01 PM), ericg (12-26-2017, 11:35 PM), Brian Drury (12-26-2017, 08:31 AM), The-J-Man (02-04-2019, 03:14 PM), civitou (02-03-2019, 04:47 PM), rebelrider.mike (01-29-2018, 10:46 PM), watts-on (05-07-2019, 12:31 PM), Dan Lim (03-02-2019, 10:22 PM), jesusangel (08-25-2019, 11:21 AM), Hanssing (04-30-2019, 04:12 AM), Fredd (11-29-2018, 08:39 AM), HyTech (08-01-2018, 09:02 AM), IronSky (03-17-2019, 12:53 AM), Mark Daniel Olsen (01-02-2018, 05:27 PM), kot (03-13-2018, 07:14 PM), Stefaan De Ridder (05-06-2019, 07:48 AM), Chiptosser (03-01-2019, 01:53 AM), BlueSwordM (09-07-2018, 02:24 AM), Johnny Stauersbøl (10-31-2018, 07:45 PM), Dennis Van Hoek (10-22-2018, 11:57 AM), KaminoReal (05-25-2019, 07:31 PM), Shade (03-25-2018, 01:21 AM), KtB (11-09-2018, 10:48 AM), Daveyboy (08-12-2018, 02:10 AM), al4sound (08-24-2018, 01:45 AM), Seedser (08-03-2018, 12:07 AM), Mazlem (05-07-2019, 02:39 PM), ivnz (09-08-2018, 03:25 AM), Geek (05-06-2019, 06:14 AM), SWEwall (05-11-2019, 07:08 AM), Bigfillly (12-31-2017, 04:54 PM), Jon (10-08-2018, 07:23 PM), jamesk9 (01-08-2018, 11:54 PM), mr_hypno (10-26-2018, 05:49 PM), floydR (02-03-2019, 02:09 AM), AlexCPU (02-07-2019, 10:44 AM), Learjet (01-27-2018, 01:59 PM), morrisok (01-01-2018, 06:30 PM), Grumplestiltskin (05-15-2019, 07:24 AM), SemaJG (03-05-2019, 12:15 PM), Lucian Macota (08-24-2018, 09:21 AM), Joey T-Bone Smith (01-12-2018, 09:58 PM), ChrisD5710 (05-06-2019, 08:00 AM), Han Mohr (01-01-2018, 10:03 AM), ap103 (10-16-2018, 02:31 PM), Jason.T.Keenan (12-27-2017, 02:19 PM), cristof (10-26-2018, 07:43 PM), Oderus420 (01-20-2018, 02:07 PM), Oz18650 (05-06-2019, 09:18 AM), accoelho (01-08-2018, 03:10 PM), neurocis (12-27-2017, 06:54 AM), rev0 (01-01-2018, 08:40 AM), Barnesy (12-26-2017, 06:14 AM), how about that (08-09-2018, 07:54 AM), okent (11-21-2018, 10:52 PM), not2bme (08-24-2019, 06:14 PM), paz45 (01-08-2018, 04:11 PM), dmallia (09-06-2018, 08:14 PM), Everythings-stuck-together (12-26-2017, 01:34 PM), CarelHassink (08-02-2018, 06:26 PM), IAMJAMESMANNION (12-29-2017, 08:12 AM), Dave Adams (12-26-2017, 05:18 PM), Pavel Razzorenov (08-19-2018, 08:36 PM), Spkerking (12-26-2017, 10:42 PM), Filip (12-27-2017, 07:33 PM), karmi27 (03-01-2019, 04:18 PM), modido (01-01-2018, 09:34 AM), Stramon (08-12-2018, 06:38 AM), DropB3ar (04-05-2019, 02:59 PM), jestronix (12-26-2017, 11:12 AM), Ben Hooker (10-26-2018, 02:31 AM), heynow999 (12-30-2017, 02:57 PM), bigblue (03-03-2019, 05:45 AM), echo (01-20-2018, 01:56 PM), Solexx X (08-12-2018, 06:33 PM)

Forum Jump:

Users browsing this thread: 1 Guest(s)