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Yes around 55C / 131F over couple of days. At 44V it adds 3.6kWh each day. Covers the losses and some use. I have since added boost DC-DC converter to run it at 300 - 500W due to excess solar. Have not ran grid powered element for a month. Daily use averages 5kWh/day.

You can also run it from 120V and turn your 4500w element into 1125w.

Starts with R ends with D.

I just love setting up high gain directional antennas to get high speed internet where there is no signal. Here is my last project I did for relatives in a remote eastern European village. Getting 100 Mbit interned where there is no 4G service was great.

OP can easily fit 30 - 35 kW worth of panels on his roof. No energy conservation necessary.

I snooped around a bit and found 5 houses with PV so far. There are more in Seven Hills.

Wow, impressive. How many square feet is your house and roof?

That's a huge bill. How many kWh per month? Do you have roof/yard space for solar panels?

Mine is very old GE SE50T12AAH but here is similar 50 gal dual element tank.

I have 67 gal dual element tank. I run lower 240V element direct from DC at 48V which makes it pull 150 watts. Lower thermostat is bypassed. Upper element runs from the grid as backup on demand heater.

Post pictures of panel serial numbers.

Looks like older type cells using flat interconnect ribbons. Modern panels use thin wire interconnects. No panel labels or datasheet listed. No indication these ship from USA.

What school and class is that? You should not be soliciting external advice on your homework.

You can take simple 120Vac/12Vdc switch mode adapter and run it on DC. Should be good up to 180Vdc. Not sure how it will behave at low input voltage at dusk/dawn.

Sounds like EVE is covering their ass in case customer uses their cells for too long and causes a fire (dendrite growth?).

Cheaper relative to what? Could do Growatt 5000es + 100Ah 48V rack battery giving you up to 20A at 240V and custom L2 EVSE with adjustable pilot charge rate signal telling your EV to reduce or turn off charging based on solar power and battery SOC.

From internal views they look contained in rigid frame but have no compression foam in between the cells. As cells age they will overcompress themselves. I would not buy rack battery because of it.

No. Graphite also irreversibly swells and cracks over time. Compression keeps it in contact with current collector foil. Good luck limiting your cycle depth to 10 - 20%. It will probably swell anyway. That they yet know of. Do they regularly test cell's remaining capacity? Will have to compare...

Good tip, thanks. Found TI app note about it. I guess I can start with 1:100 feedback ratio or 270k resistor and go lower from there.

Sure, one guy that goes against mountains of research that proper compression does increase cycle life.

I came up with this circuit to automate bypass contactor closure. It's a comparator that turns on once the difference between battery voltage and load side voltage drops to within 1V. Need to add latch circuit to prevent possible contactor chatter or oscillation.

Is that a 48V inverter? Those IRF2907Z are 75V MOSFETs. Interesting that 1st tier brand would leave so little voltage headroom.

No point in using GaN at 12V. They probably used better newer MOSFETs in bidirectional buck-boost topology.

Now I am (again). Forgot about it. My batteries may be closer to 82% SOH. I try to keep them below 50% state of charge and not leave them charging unattended. Will have to move them outside soon.

Great info. Calendar aging may not be linear so initial loss of capacity may be greater than loss when cells age a bit. My 85% SOH Panasonic NCR18650B NCA cells (from ~2013 Tesla model S) seem to be losing 0.6% per year when stored at room temp around 27°C and 50% SOC.

Comes out to 37 cents/Watt using 370W panels, 25 c/W for 550W panels. Seems competitive using large panels plus cost savings of not needing to rent and operate pile driver machine. Panel attachment method seemed awkward at first but that ratchet wrench makes it work.

Victron Phoenix 48/800VA uses Ruichips RU1H80R 100V 80A 9mOhm transistors 2 in parallel without heatsink but fan cooled. They are very similar to IRFB4410. I am running this inverter at 640 watts and i can hold my finger on the case of one of these transistors without getting burned. Pretty...

Found couple FT240-31 chokes and measured their attenuation. Here are results in dB for attenuation for 20 turns, 26 turns and both of those chokes connected in series. Right table side shows difference between two chokes in positive attenuation dB. For example at 28.3MHz going from 20 to 26...

No. Inverter converts PV to different voltage and 3 phase. Calculate by power, not current. You can do 16 * 550w panels in series * 2 parallel per MPPT input = 672V * 26A = 17.47kW * 4 MPPT inputs = 69.9kW PV STC total from 128 panels per inverter. Open circuit voltage at coldest temp will be 16...

I meant excessive in cost of equipment used.

Parts harvested from dead Aims 1500W 48V inverter that will become DC-DC converter for Midea aircon. E55-N2Z0Q 48V/120V 4:17 ferrite transformer good for 3kW surge. Measured 90nH primary leakage inductance with secondary windings shorted. Full bridge driver and rectifier circuit. SG3525 PWM...

And I thought Engineer775 installs were excessive. This one wins hands down.

I like it cheap and simple (and efficient) :ROFLMAO:

I think cheapest equivalent RV solar system will be 3x 400W $156 panels, $468 total. Run 9x LF304K cells in series for 30.6V charging voltage direct from panels wired in parallel and without MPPT but via simple DC contactor controlled by battery voltage detector to protect cells from...

Check MOV continuity to ground on that thing. If PV- gets shorted to ground your inverter could blow it's IGBTs.