This may have been discussed before but its good to talk about it... most inverters need a battery bank or the grid to make AC....but why they do is not understood by many..in other words you can't turn solar DC directly into usable 240v without some kind of reference constant device..there are some inverters that will allow some AC to be taken from the box itself but they still need additional things like the grid or something ...I'm sure that there will be some models in the future that will do this....micro inverters need the grid also....lets hear from an engineer on why its difficult to just run DC thru a circuit and use the AC output..like charging an EV with 240v AC...
no battery inverters
- Thread starter e67
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sunshine_eggo
Happy Breffast!
There are some "hybrid" inverters that can be powered exclusively via PV - advertising "batteryless" operation.
These use the high voltage battery of hybrid vehicles as the PV input and get AC output.
These use the high voltage battery of hybrid vehicles as the PV input and get AC output.
The MPP 6548 has batteryless operation...
Only in unpaired mode though.
So, 120V is all you can use without battery bank, but it claims the ability.
Only in unpaired mode though.
So, 120V is all you can use without battery bank, but it claims the ability.
I almost posted as soon as the battery-less was mentioned but I'm not sure I can claim it the same way its being mentioned.
I run battery-less powering my house in hybrid mode. I have no clue if it can run with no ac(grid) and no dc(battery) and still power up.
It might but I have no idea and kind of doubt it.
I run battery-less powering my house in hybrid mode. I have no clue if it can run with no ac(grid) and no dc(battery) and still power up.
It might but I have no idea and kind of doubt it.
400bird
Solar Wizard
The issue is that both the sun and your loads vary. If the sun goes behind a cloud and you turn on to many loads, the power goes out or browns out. It is possible to run without battery or a grid connection, but the actual use of it wouldn't be great. Plus no power at all once the sun is down.
hwy17
Anti-Solar Enthusiast
When the load exceeds the solar generation there is only one thing that the inverter can do, shut down.
It must shut down because lowering its output is dangerous for the load devices, and many load devices don't care if you lower voltage they will just suck more amps to get the same wattage.
The load will exceed the solar generation way more than you think from a cloud or from inrush current. Incandescent bulbs and motors can both draw many kw for less than a second while they turn on.
With a big array and a small load it is possible. Sunny Boy inverters have an "emergency outlet" feature that can be powered by solar only.
It must shut down because lowering its output is dangerous for the load devices, and many load devices don't care if you lower voltage they will just suck more amps to get the same wattage.
The load will exceed the solar generation way more than you think from a cloud or from inrush current. Incandescent bulbs and motors can both draw many kw for less than a second while they turn on.
With a big array and a small load it is possible. Sunny Boy inverters have an "emergency outlet" feature that can be powered by solar only.
Yes , if clouds kept changing the internals of the inverter, the it would be impractical ,the EV charger might react and reset and the whole thing would just keep resetting and shutting off and restarting...and maybe burn out. So a constant is needed I guess...
so maybe the best device will be a DC to DC box that is rugged and constant and won't trip any alarms on the EV charging circuits..and shut off the batteries from taking a charge if that is possible I don't know.... probably won't be built by a car maker though...
so maybe the best device will be a DC to DC box that is rugged and constant and won't trip any alarms on the EV charging circuits..and shut off the batteries from taking a charge if that is possible I don't know.... probably won't be built by a car maker though...
Yes a standard battery inverter can power the EV charging. Generally need 16 amps at 240v minimum or about 4kW inverter. The battery will reduce the cycling and absorb ALL of the solar until full. Need a solar controller to charge the battery. Just a matter of how much solar and battery you want to go. I recommend 48v battery. With a decent battery and 6 kW solar it may run mostly continuous. Not hard to implement.
On a low budget 12 amps at 120v can go with a common 2000w inverter and less solar.
How many miles do you expect to gain each day? Might get 3 miles per kW solar. So 1000w solar might net 15 miles per day. YMMV
On a low budget 12 amps at 120v can go with a common 2000w inverter and less solar.
How many miles do you expect to gain each day? Might get 3 miles per kW solar. So 1000w solar might net 15 miles per day. YMMV
GridWorks Green Solar
Solar Innovator
Have a working no battery/no maintenance solution that is providing main Air conditioning and more to a 1,400 square foot home.
18-12VDC solar panels and about one half amp of secondary grid power. (Can be sourced in other ways.)
Seamlessly backed secondary power for after hours usage.
Link leads to main documents and detailed descriptions on page 22, If you are not familiar with my thread please start at the first post and read all mains power and capacitor discharge warnings
diysolarforum.com
Project just ended with a big success ?
Yesterday got 9.5 hours of continuous PV powered Air conditioner and more.
18-12VDC solar panels and about one half amp of secondary grid power. (Can be sourced in other ways.)
Seamlessly backed secondary power for after hours usage.
Link leads to main documents and detailed descriptions on page 22, If you are not familiar with my thread please start at the first post and read all mains power and capacitor discharge warnings
New no battery pure sine wave solar power system with smart switchers.
New solar sensor is beyond cool tiny dead band prevents it from acting like a blinker FET looks for real change in the sensor voltage before changing the output mode, seriously good design ? What you have here is the results of massive trial and error approach and not accepting no or...
diysolarforum.com
Project just ended with a big success ?
Yesterday got 9.5 hours of continuous PV powered Air conditioner and more.
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GridWorks Green Solar
Solar Innovator
Thanks for your interest, I invited all thoughts and discussions, the main point of the project was to dump the costly batteries and make a maintenance free PV power system, my older system needed 4 new deep cycle batteries at $2,400 replacement cost. It became apparent to me the Exidy battery company was the big winner in my solar adventure to go green and save some cash.
Currently running main A/C 120VAC mini-split, Fridge,lights and more off the 18 12VDC solar panel 180VDC configuration groups of 9 series solar panels, Grid/Secondary power is making for a good solid platform to support intermittent clouds and after hours operation.
The system as it sets is 98 percent good,
Has performed well for months now, I will detail here the remaining potential issues, Ever had it raining in the front yard and sun shining in the backyard? This will cause a resetable fault/trip also loss of Grid/secondary when PV energy is not enough will cause a similar trip. (Currently blows a 10amp glass fuse but will soon be replaced with a easy to reset breaker.
Have considered super capacitors and other forms of temporary energy storage but the cost quickly rises to the point where your back to purchasing batteries again, The current project DIY cost is under $3,000 planning on additional 9 solar panels for the full array so let's just round it up to $4,000, other system have price tags of 25,000,36,000,39,000 and 69,000 payment plans. I suggest you do the math for your self and study real customers reviews before putting a pen to paper.
Maintenance on the DIY system consists of keeping the PV panels clean and resetting the system once in a while my best guess is once every three months or so.
The system preforms above normal expectations in overcast conditions and in full sun the presence of Grid voltage at little to no current excites the panels into producing noticeably more energy.
Much more study needs to be done here on this, early testing points to big difference in type age and construction of the solar panels with mono silicone having a noticeable advantage, In the other thread is two quartz tube heaters in side by side photos the one on the left is dim directly driven PV, the one on the right voltage boosted with Grid voltage but zero current draw, all I can tell you the one one the right side feels great on a below freezing day.
If you want to see it for yourself put 9 standard 12VDC panels in series, be careful 180VDC! in sunlight, and claim the 180 volt Deluxe Inverter being offered for free in the other thread, no strings attached but if you like it just tell others about it, great head start to the full system.
My aim is to have as many working examples of this unique power system as possible before my retirement ends.
Best wishes to all
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