This can only be answered accurately if you know what your daily energy consumption is, more importantly what energy you consume Overnight, as becoming energy independence starts with you Sunset to Sunrise energy consumption!
As the Energy Storage provides Free power until Sunrise, where Solar takes over again.
Think of a Solar Array as being like a petrol bowser, Solar fills-up the Batteries with what would normally be Unused/Excess energy, all whilst operating your home/premises, selling this energy for 10c kWh as a Feed-in Tarrif (FIT) & later paying 30c kWh for importing the energy back from the State Grid after Sunset, as a Generator, this is taking a step backwards & away from Energy Independence !
Remember: Energy Storage is easily removed and take to the Next location!
The Final Item required to become Totally Energy Interdependent & Black-out-proof your premises, is a small cheap $900, 3.5kW, Silent (58dB) fuel/LPG/bio-gas Generator, that Gen-set has a starter motor & battery, If your Inverter has AGS function it starts Automatically as Programmed. There is no real need for a huge 10kWh or larger Generators when the Batteries get low, as all single phase State Grid Power is 3.6kW (3'600W) with 15A+ load.
As an example;
- A Consumption of 20kWh energy each day, with commonly 25~50% of energy consumed after the Sun no-longer strikes the solar panels.
- Peak & obscure Solar energy Generation varies greatly based on the solar Racking;
Fixed Panel Racking commonly Generates Peak energy between 4~5hrs Day.
SAT Racking Generates energy between 6~8hrs Day.
DAT Racking Generates energy between 10~14hours per day.
NB: Energy harvesting times relates to your latitude location, DAT harvesting is superior the further south of the equator you live.
- Taking into account the above, we recommend installing a pole mounted DAT Module and Not to overspend on Solar Panels, instead invest in Battery storage equal or preferably greater than your overnight or 24hours of energy consumption, as it is Far better to Store more energy than you consume, so that after Sunset & through to Sunrise you will be self consuming the energy you harvested during the day, and Not need to purchase energy via the State Grid!
The only exciting thing about Australia's expensive Retail energy rates is, all small to large residential energy consumers spending between $100~$1'000+ a month on there energy bill, can be Self-Fund by purchasing Solar & Battery Micro Grid in 4~6 years with there energy savings!
Over 90% of consumers can actually get a personal loan to purchase & install a Micro Power Grid, that in turn will Self-Fund the investment, it's that simple!
REMEMBER: Batteries are the critical component that allows you to self consume ALL the energy you harvest, and in-turn Not having to rely on the state grid.
Totally energy independent require 3 items;
- Solar array that harvests at lease 24hour of your highest daily energy consumption, NB: DAT solar Racking is the Best!
- Battery storage: The minimum Energy storage system should be what your consumption is between Sunset and Sunrise, the more energy storage the better, especially during extender bad weather, and additional energy storage Greatly extend the life of all Batteries, due to less stress being put on them while operating at a Lower Depth of Discharge (DOD), that is commonly what reduces Battery cycle life.
However, Super Capacitor Energy Storage Modules are NOT affected by 100% DOD, and have a 50'000 Cycle Life.
- Hybrid Inverter: Are the Brains of all energy systems, if anything is going to Fail, It'll be the Inverter, as inverters manage all aspects of your micro Grid/system, premature failure can be caused by Insect invasion, that can be stopped by micro as the Heat generated . Some Hybrid inverters have a AGS (automatically generator start) function. If you already have a Solar only Inverter we recommend you replace it with a Hybrid inverter & keep the old inverter as back-up, or you will need to purchase additional equipment to be able to incorporate a battery bank into your system, Hybrid inverters offer the option to Plug & Play Battery into the system when ready!
Energy Independence is seriously that simple. No matter what your daily energy consumption is, the MOST important purchase is the correct size Energy storage bank ! As energy stored is like a fuel tank, the larger the capacity the longer it will last !
Investing in Energy storage equal or larger than your 24hour consumption, will definitely put WAY LESS stress & demand on the batteries over time, and this in turn will Greatly extend the life of all batteries, with the exception of NiFe battery's & Super Capacitor banks, that commonly reported to last over 30~100+ years.
Think of a Solar Array as like a petrol bowser, solar tops-up the batteries with unused/excess energy whilst operate your premises.
Technically it's a Lot easier and cheaper to add solar panels to increase your Energy Harvesting, where adding battery's to your system can be more expensive & difficult depending on the battery type & configuration, as the battery Voltage need to matched the existing system voltage (modern DC voltage is commonly 48VDC, but can be up to 750VDC).
Other forms of Generating Energy like Wind, Aqua and fuel Generators, where fuel generators are now being operate on Bio-Gas or Waste Vegetable oil, to further black-out proof your premises, if you are intending to go off-grid, only a Hybrid inverter will allow multiple power inputs in one unit.
If you already have Solar: You possibly have an array that harvests energy in excess of your daily consumption!
As Fixed-Tilted solar Panel Racking ONLY harvests Peak energy for 4~5 hours per Day, compared to 10~11 hours Day for DAT Units, that use approx. half the Panels to Generate the Same kWh of Energy.
Retailers sell as many solar panels as possible, The main reason behind that, there is an Elephant in the room, it's the STC credits (the Customer can Claim) the Retailer get you to sign over, then they claim 11 years of your STC credits, being upwards of $3'000~4'000+ for a 6kw system, Plus the Profit they make on the supply, not bad for what should only be 1/2 Days work!
Solar Retailers are part of the oversupply, there TV solar sales pitches are based on the lucrative STC refund they claim, don't believe us, then ask them what is there cost to "Just Supply all the Equipment".! We have done this several times, it always comes in at double there advertised price!
A solar array can eliminate or reduce most customers daytime energy bill !
However, without Energy storage (batteries) the customer is forced to pay 300% more than any Feed-in-Tarrif (FIT) for energy imported Back from the state grid.
If you are one of the consumers that already have solar, you are currently in a great position, as the minimum kW Battery size should be the kWh you consume between Sunset & Sunrise, as mentioned, the larger the kWh storage the better you will be in extended periods of bad weather.
If your solar retailer did not advise you well, you will have a solar only inverter, we advise everyone you invest a few hundred extra for a Hybrid Inverter, and keep your old inverter as a back-up, in case of inverter failure, whatever the cause may be.
Again, Solar Only inverters do Not have a battery charge function, or allow for additional energy inputs like diesel Generator, Wind, Aqua etc. - If you don't purchase a Hybrid inverter, you would need to invest in additional stand alone equipment like MPPT unit, Charge controller, AC converter, disconnect fuses-n-switches & additional wiring etc., making for a more complicated system, where in turn each unit consumes more energy to operate your system.
Again, assuming that your solar has already paid for itself in energy savings, the investment in batteries for after sunset consumption, will commonly only take 1~2 years to reach break-even investment point, based on self consumption of all your own energy.
If your solar array harvest more energy than you consume and you remain grid-connected, you will have the option to export what would normally be wasted energy, for a feed-in tariff to cover the state grid connection fee of $80 ÷ $0.10c kWh FIT =800kWh Energy to Export just to cover the "Remain Connected" Fee, that $80 (800kWh) is then been Sold to your Neighbours for $240 (@$.30kWh), in turn the Retailers are Charging Customers to make 300% profit for your .