The way AC coupling throttling works is that our AC electrical system runs at 60hz (50hz). If there is more power being made that the house needs, the power goes to the battery as if it was a surge tank and within about 1 second, the system frequency changes toward 62hz. The idea for this comes from gasoline and diesel generators... they are made to idle at 62hz (3720rpm). As you put load on them they pull down to 60hz. now imagine a balance where your generator is just idling providing a very small amount of power to your house and you turn on the stove and it bogs the generator down from 62 to 61.3hz. You solar system would see this and wake up and start making a little extra power. Now imagine we simulate the loading and unloading of the generator with a battery inverter's software. BOOM... now you know how the UL1741SA frequency control works.

Over the weekend I found that you can buy chinese server rack batteries for $689. Check the Energy Storage System on Alibaba app👉 https://x.alibaba.com/AwqpgJ?ck=pdp

I can’t vouch for these but $688 for 100ah server rack with canbus BMS. I think the 200ah (10kwh) variants are $1200.

Batteries are getting really really cheap. There will come a day where the lower prices will be eclipsed by the diminishing value of the USD. So thread the needle folks.... when you see the value of the dollar dropping, if you want batteries or any other things that aren't made here, start buying.

The difference between PWM and MPPT charge controllers. PWM is limited to the amps the solar panel can provide. MPPT can convert the higher voltage of a panel to even more amps. See attached picture.

Thermostat for direct hot water heating from solar panels. 3 250-275w panels and this thermostat and you’ll have hot water.

Is it hot in your attic? Why not run a bunch of pipe up there to soak in the heat all day? When you take a shower the hot water heater inlet can be connected to the pipes in the attic and you can refill the hot water heater with 100F water instead of 50F water.

if you use 2" PVC pipe, be sure to slope the lines in such a way they will drain completely in winter. hint: 250' of 2" PVC will give you 40 gallons of warm water.

This week is "clean up and organize the workshop". We sold our house 2 years ago, moved here and built the shop. We haven't stopped long enough to organize anything. I've got fence parts in three places (basement, barn and workshop) for example. Consolidation and organization is my thing this week.

If I think of something off griddy I'll post, but there won't be an "off grid" project this week.

Cleaning up in shop. My first bus bar before I knew better.

My 3 layer wood working screw tool box

Top drawer out

Second drawer out

The box has a simple old elec cable drilled and a knot inside the box and swivel castors on the bottom
I pull it to where i am working and voila'
No walking up and down

Its about 25 years old. Great thing is you not carrying screws up n down in tins and having to put them back.
Its also easy to do inventory and see what you need at anytime.

I have different "stock box" tool boxes for various things

https://www.youtube.com/watch?v=qpPYkqpe-Ms

This guy is the real deal. Back 6 or 7 years ago, he bought a crashed tesla battery and used it to replace his old lead acid batteries.

Family
@survival4u

World's most expensive strawberries

Waking up with 68% battery since sundown last night. Here's energy generation (dk blue), export(lt blue) and usage for HVAC(purple) and my car(orange) yesterday. Note that export takes off sharply after 1pm... that's when the batteries got full from the previous night and 100% of my system was dedicated to export.