Need Advice on 25 sunpower 240s and Magnum Quad MS448 plus batteries (Hybrid System).

[naples]

The set up will be 3 panels.
• Panel 1 – grid (feeds to panel 2)
• Panel 2 – generator (feeds to panel 3)
• Panel 3 – solar

The purpose of the magnum is to:
1) Provide the sign wave to the solar panels so they work when the grid is off.
2) To charge the batteries.
3) To discharge the batteries – power the house.
4) To turn off the solar panels when there is no place for the power to go (grid off and batteries are at full charge).


• When the grid is on the grid charges the batteries and the solar feeds back to the grid (lower power bills)
• When the grid if off and the generator is on, the generator acts as the grid, (not sure how the solar panels get shut off though)
• When both grid and generator are off, the solar will charge the batteries and shut down after fully charged.

So it’s the best of all three worlds, grid, generator, batteries. The longer power is off, the less you have to power your home

1) Grid is full power, all panels 1,2,3
2) Generator is less power, only panels 2 and 3,
3) Batteries are essential power, only panel 3.

I know the battery array and Magnum is expensive, but they allow AC coupled system, I want the AC micro inverters and I also want the batteries, something that is rare and hard to set up.

Sound like a good plan.

[Naptown]

The set up will be 3 panels.
• Panel 1 – grid (feeds to panel 2)
• Panel 2 – generator (feeds to panel 3)
• Panel 3 – solar

The purpose of the magnum is to:
1) Provide the sign wave to the solar panels so they work when the grid is off.
2) To charge the batteries.
3) To discharge the batteries – power the house.
4) To turn off the solar panels when there is no place for the power to go (grid off and batteries are at full charge).


• When the grid is on the grid charges the batteries and the solar feeds back to the grid (lower power bills)
• When the grid if off and the generator is on, the generator acts as the grid, (not sure how the solar panels get shut off though)
• When both grid and generator are off, the solar will charge the batteries and shut down after fully charged.

So it’s the best of all three worlds, grid, generator, batteries. The longer power is off, the less you have to power your home

1) Grid is full power, all panels 1,2,3
2) Generator is less power, only panels 2 and 3,
3) Batteries are essential power, only panel 3.

I know the battery array and Magnum is expensive, but they allow AC coupled system, I want the AC micro inverters and I also want the batteries, something that is rare and hard to set up.

Sound like a good plan.

How is your installer accomplishing the red portion above?

[naples]

How is your installer accomplishing the red portion above?

Thats one of the reasons for the magnum, it charges the batteries till they are at full capacity and then
turns off the solar panels (stopping the sine wave) when they are fully charged and the grid is off.

[Naptown]

apparently it does not shut the array down according to this diagram from Magnum

http://www.magnumenergy.com/Literature/Application%20Info/Magnum%20AC%20Coupled%20Line%20Diagram%20(1-May-2010).pdf

They show a diversion control and diversion load for battery management (see lower right hand corner of drawing)
I would imagine the same thing could be accomplished using a relay or series of relays to shut down portions or the whole array.

[Fatawan]

Maybe this can add some additional flavor

http://solarprofessional.com/article/?file=SP5_5_pg74_Schwartz

[Naptown]

They still recommend a diversion load
Also check that your micro inverters are supported warranty wise for this application

[Aalbertz]

Off-Grid Domestic Solar systems

Off-Grid Solar systems with batteries have always been an issue for contention. The finance of that amount of batteries will never allow a payback as the batteries need to be replaced every 6 -8 years or so (at best). A better solution is to take that power that is generated in the day and convert it into useful energy that is stored within your boiler (hot water tank). There are a number of systems that do this. This way you still get the tax credits for the solar but you also get free hot water which reduces your energy bills. There is a product in the UK which is doing quite well called the Immersun, not sure of the American equivalent. Similarl yxxxxxxx offer some solutions for off-grid and remote power systems, however as you may find if you research this deeper domestic is not as feasible as you would hope.

[inetdog]

Off-Grid Solar systems with batteries have always been an issue for contention. The finance of that amount of batteries will never allow a payback as the batteries need to be replaced every 6 -8 years or so (at best). A better solution is to take that power that is generated in the day and convert it into useful energy that is stored within your boiler (hot water tank). There are a number of systems that do this. This way you still get the tax credits for the solar but you also get free hot water which reduces your energy bills. There is a product in the UK which is doing quite well called the Immersun, not sure of the American equivalent. Similarl yxxxxxxx offer some solutions for off-grid and remote power systems, however as you may find if you research this deeper domestic is not as feasible as you would hope.

If all you are going to be doing with your PV is heating water, then you will get a far far greater return on investment from using solar thermal panels to heat the same water.
Only if you will be using most of your PV electricity as it is generated and just want to find a use for the rest which you are not allowed to sell back to the grid, does this type of opportunity load come into play.
Or, of course, in the UK if you are payed a higher incentive price per KwH for power you generate and use than for power you return to the grid. (Topsy-Turvy anyone?) That is the intended market for most if not all of the commercial power balancing systems that heat water.

[Aalbertz]

Solar hot Water

If all you are going to be doing with your PV is heating water, then you will get a far far greater return on investment from using solar thermal panels to heat the same water.
Only if you will be using most of your PV electricity as it is generated and just want to find a use for the rest which you are not allowed to sell back to the grid, does this type of opportunity load come into play.
Or, of course, in the UK if you are payed a higher incentive price per KwH for power you generate and use than for power you return to the grid. (Topsy-Turvy anyone?) That is the intended market for most if not all of the commercial power balancing systems that heat water.

In the UK you get paid both for power you generate and power you export regardless of whether you use it or not (if you don't have a meter). Rightly so, if you are in during the day using power then there is not spare electricity to heat hot water, however if you are out then this power goes to the grid at 4.5p/kWh and when you are paying 12p/kWh to heat your hot water (even more for electrical heating) it doesn;t make sense to export it. Of course that is just the UK, it probably is entirely different for the US. Most Commercial Installations use the entirety of the power generated by their systems (roof Mounted). Therin lies the gap in the energy market that is dominated by so few: we can produce electricity cheaper than they can providing there is sufficient renewable resource to cover the base load using