Most people that are looking at installing an energy storage system (battery and battery inverter) don’t realise that every installation is different and there is no one size fits all. Installations are very dependent on whether there is already solar PV in place and the current electrical wiring situation at the premises.
With solar PV installations as long as you have suitable roof space you can install a system and the questions that need deciding are finding a reliable supplier / installer, working out the size of the PV system needed according to electricity usage and roof space and the size of the inverter required.
With an energy storage system it is much more complicated. Among the considerations are;
Is there a current PV installation? (Installation decisions will be different, and can be more complicated, compared to a new combined solar / battery installation).
What solar inverter is attached to current PV installation? (This can determine what batteries can be installed without replacing the solar inverter and how an energy storage system is wired).
How old is the current solar PV inverter? (Only newer inverters are capable of being connected to energy storage systems and not all inverters work with all batteries).
Is the inverter suitable for connecting to batteries in general and in particular to the particular battery technology you are looking at? (If the solar inverter is not suitable it may need to get replaced or the battery inverter may be able to get wired directly to the PV panels via a solar MPPT).
Does the installation have a string inverter or individual micro-inverters? (AC Micro-inverters cannot be connected to all battery technologies).
Do you want the system to be wired as an AC system or a DC system? (Each of these systems have pluses and minuses, including the ability to have power when the grid goes down and the cost of initial installation, particularly with a retrofit to a current PV installation).
Do you need power when the grid goes down? (Not all batteries are capable of providing power when there is no grid connected and batteries that can provide power when there is no grid need to be wired differently).
Do you want the complete house to run when there is no grid power or only a dedicated circuit that has refrigeration, lights and maybe one or 2 power points? (This will determine the size of the battery needed and the amount of extra electrical rewiring of your house to put the required items on a single circuit and some thought as to what should go on that dedicated circuit).
How long do you want your house to be able to run autonomously, a couple of hours or a couple of days? (If you want a couple of days you will need a much bigger system)
How much power do you use during the day? How much of this total usage is at night? (This will determine the size of the battery needed).
Do you want a percentage of your battery to be available at all times in case of a power failure? (This will determine the size of the battery needed).
What appliances do you want to run simultaneously? (This will determine the size of the battery inverter needed).
What area do you have available to install your energy storage system? What battery technology are you looking at? (Different battery technologies have different installation requirements. Lead acid batteries and some lithium batteries have to be housed in a separate dedicated room that is well ventilated to prevent explosions from build-up of hydrogen gas. Lithium ion batteries (under new regulations) cannot be in a habitable room or within 600mm of any window or door and need to be against a fireproof wall or have fireproofing installed behind, above and below installation. If installed in a garage lithium ion batteries need to have a bollard installed in front of them).
These are just some of the questions you need to think about when installing a battery energy storage system and are really about making sure the battery system is designed for your needs. If you aren’t asked these questions you need to ask if the salesman / installer is trying to find out the best system for your needs or just trying to sell you the system they want to sell you.
If you would like to know more about getting a safe, reliable and recyclable battery energy storage system for your own home, business or micro-grid to increase your energy independence visit us at http://quantum.GridEdge.com.au. We have a number of different sized systems that can cater to your budget and household needs.