Does exist any modular system for multiple sources and storages ?

• Does exist any modular system for multiple sources and storages ?
  Posted by Miyuki on 03 May, 2018 12:08
• Hi,
  
  Im thinking about home installation and I want to add more panels and maybe even wind in future and also battery storage
  
  Everyone I saw have panels with charge regulator to batteries and then DC/AC converter, or have direct solar to AC inverter grid tied
  But with this system is problem to add other components or change something
  
  Does exist something like common DC bus to which I can connect multiple panel arrays, multiple batteries with charge/discharge controller (can have any voltage and chemistry), have separate DC/AC and have like grid backup feed to this DC bud
  And at best be open source system ?
• #1 Reply
  Posted by Rerouter on 03 May, 2018 12:34
• What your after is the more expensive type of  inverter, the non grid tie ones, one that can take panels, mains or batteries as an input, and batteries, mains or local AC as an output.
  
  I havent really read to far in to them, so I cannot give any examples
  
  Depending on what path you head down, some manufacturers allow multiple units to be connected in parallel for future expansion, however most cases it is closed source, but open data protocols, or atleast at request, or via free software that is not hard to rip apart.
  
  Based on your knowledge of the subject it hints to me that you want to keep things cheap, however its very rare that the dedicated shared DC bus thing works, as in most cases that is the batteries, equally unless built for it, most battery chargers do not play well near float voltage when in parallel,
• #2 Reply
  Posted by Miyuki on 03 May, 2018 13:22
• I know about systems with solar inverter with battery module and grid backup
  
  but I want something complete modular like PC just add next card to slot
  
  like at sketch, bus with capacitor bank, as base level and can add battery module (with internal DC/DC to charge and discharge at need), add solar panels with controller and so

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• #3 Reply
  Posted by NiHaoMike on 04 May, 2018 01:10
• That sort of design is common in telecom, usually with a 48V bus.
• #4 Reply
  Posted by controlfreak on 11 May, 2018 17:00
• There are a number of systems out like what I believe you are describing.  Something like the Schneider Electric (post-Xantrex) Conext series has a modular system where you build it out to your needs based on a common DC bus. 
  
  I installed a Conext HW system that was initially a charger/inverter module, a small battery bank, and AC/DC distribution modules (not absolutely necessary but make for a cleaner install).  Later when the client wanted solar, we were able to add two more charger/inverters to the bus and four MPPT modules feeding it.  The expandable DC bussing makes it easy to bolt new modules in after installation.  It's not the least expensive option, but it's well-supported and I have not had any issues adding modules to increase capacity or add functionality. 
  
  Another system I have worked with is Victron's.  They're not as polished as Schneider's offering (wiring between modules visible, they don't integrate together), but they are still great to work on.  I don't know about longevity as I haven't worked on any old Victron setups yet.  They offer similar stuff, where you can mix/match inverters, chargers, inverters/chargers, MPPT modules, battery banks, etc. 
  
  Those are just the two I have recent experience with, but there are several more manufacturers making that type of system.  Both of these systems have some interesting features, like being able to output three-phase power with only the DC bus (powered by PV modules, batteries, etc) and/or single or split phase AC (not useful to most people, but for my needs it's perfect). 
  
  It's a matter of how much you expect the system to change, how much you're willing to invest up front, and how long you reasonably expect to use the system for.  You can get a barebones setup for a reasonable amount - I am gearing up to put one in my house to have a battery backed circuit (no solar possibility where I live, and relatively frequent power outages) for around $2500 including batteries and all sorts of unnecessary accessories to make it more integrated. 
  
  Edit:
  Here's a picture of a random Conext setup I found on Google.  It's a larger one, for sure, but should give you an idea of how it looks when it's fitted together.
  

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