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excess power battery charger?
There are inverters with limiters so you don't export power, but are there chargers which are designed to use excess power, to limit current based upon input from a CT?
A power diverter mated with an intelligent charger to do all the CC/CV/setpoints/etc.?  Or even an intelligent charger which is capable of taking the varying output of a power diverter? 
All the brains but able to use a limited and varying current source? and work with a BMS?

A Victron ESS does that - and a lot more.

Any AC coupled surplus is diverted to battery, any DC coupled surplus (in the event of battery full) is used to support AC loads - if you've a Fronius inverter, or one that supports frequency shifting you can either set grid export to zero or allowed.

I suspect you might wish to clarify your question.

Thank you for your information on the Victron system. I will spend more time going through their information; it has been interesting so far. I was dismayed at the costs though. As I understand it, the most basic system would cost thousands, NOT including battery, BMS, charge controllers, solar and safety.

Are there other companies who produce similar systems?

(04-03-2019, 01:07 PM)rearden Wrote: Are there other companies who produce similar systems?


Yes lots, if you add more info (such as expectations of storage and use etc) you will get a more defined response.
(04-03-2019, 01:41 PM)Sean Wrote:
(04-03-2019, 01:07 PM)rearden Wrote: Are there other companies who produce similar systems?


Yes lots, if you add more info (such as expectations of storage and use etc) you will get a more defined response.
I am slowly collecting batteries, so as much as I can store but a few kwh may take a while.
An incrementally expandable system to store excess grid tie or other solar power and use at night.
It would be Real Nice to be able to have the capability for serious backup power.

I have 16 Enphase grid tie M215 inverters.  I do not live in a net metering area, so any excess power is donated to the power company.  This limits the economic size of my system because any extra capacity I currently add will give me steeply decreasing returns unless I can store the energy. I am currently storing the energy by running as many devices as possible during solar production time.  But this is coarse, I am running out of devices and I generally have enough hot water already.  I have experimented with using a home automation system Vera with an EmonPi to determine when I am exporting and turn a few zwave switches on and off.

For a test system I scrounged some free sealed lead acid batteries, an Epever Tracer BN4215, spare solar panels and Samlex inverter to run specific devices (radon fan, computer network), that did not go as well as I wanted.  I am now using a spare M215 to generate grid tie power during a portion of the night from the batteries. limited by battery capacity and solar input with the epever providing load switching and voltage monitoring.

I am collecting 18650 and 26650 cells.  I currently have 40-50 of each. A long way to go.

My starting goal is to store my excess power and use it at a later time because I can't use the grid as a battery.  The most transactable (liquid asset) form of energy is battery storage.  This is probably (at the moment) 1-8 kwh depending upon the season.

The next goal is to incrementally expand the system as my battery collection grows and start storing enough to power a significant amount of needs.  I have an all electric house.  heating/cooling, hot water, cooking.

Next level and may be the only thing which justifies the economics is to have backup power.  When the power goes out my all electric house is pretty cold/hot.  Hot I can deal with, cold is another matter.  This does not happen often though.
I have split phase north american 120/240vac.  The enphase system doesn't offer any of that unless I can appropriately isolate and microgrid.  I have a back up Samlex 12v inverter for the fridge, basic power, but nothing close to power a 240v HVAC system.  This is probably a pie in the sky, but if I consider spending real money it needs to incorporate this feature and the LRA is around 75.

Other considerations is cost.  This is a hobby project which will grow over time, and I don't have the means to throw lots of cash at it.  Also safety, power generation devices connected to the grid should have appropriate certs.  anti-islanding, etc.  I am always interested in what my marginal improvement costs are and sometimes eventually come around to spending more than I initially thought I would if it does some nice stuff.

I am looking for other companies which produce a system similar to the Victron ESS.  Can anyone recommend such a system?  I am not having much luck in finding them.  Sun GTIL has an inverter with a limiter, which is a start, but it does not seem to have the ability in itself to intelligently manage the power flows between battery, grid, loads, solar, etc. 

I am looking for a system/components which will allow me to prioritize the power to loads, then battery charge, then grid export.  And hopefully also operate safely in a grid down situation.


There's a good few more .... but none can be considered cheap, few if any make financial sense either.

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