A battery is a significant investment for your home and for your future. While it’s easy to sit back and enjoy the clean energy you are producing, storing and using in your home, it pays to have a basic understanding of how your battery works – that way you can increase its lifespan and use less energy from the grid. And who doesn’t want that?
Having a solar battery requires some adjustment to your energy use habits if you want to make the most of the savings it can provide. If you want to optimize your battery even further, you may need to understand the options available to you – for example what settings you can and cannot change on your inverter and battery.
Here are our top tips to get the most out of your solar battery.
1.0 Understanding battery technology
Plico uses lithium-ion batteries in all its solar + battery systems, so we are going to use them as the basis for this overview. Lithium-ion batteries have become the most common battery type in the last decade, praised for their versatility, industrious nature and safety.
As with all lithium-ion batteries, the PylonTech US3000 used in Plico solar + battery systems has a limited Depth of Discharge (DoD). This is the maximum capacity of the battery you can use without degrading it. Lithium batteries have a standard 90% DoD. So, if your battery’s capacity is 14.2 kWh, it has a maximum useable capacity of 12.78 kWh. However, it's not recommended to set the DoD to 90% - the recommended setting is 85%.
You can set your battery up to have added blackout protection by increasing this DoD to 80% so you'll always have ‘extra gas in the tank’ should there be a grid outage. Your battery will power your home’s back-up circuit during a blackout and can be charged from your panels so long as the sun is shining. Just reach out to us if you'd like your battery's DoD changed.
The lifespan of your battery is an important consideration. PylonTech batteries have a cycle life of 6000 cycles – one of the highest on the market. This cycle life is built into every Plico battery – however this can be affected by how you use your battery. Read on for tips to maximise your battery cycle life.
If you’re in the market for a solar battery, read our article on the Best Solar Battery Storage in Australia 2022.
2.0 Do the maths
It’s important to understand your battery capacity in terms of the amount of energy your home is using. This comes down to some simple maths – we promise we won’t bore you!
If you have a 7.2 kWh battery set to 80% DoD (for battery preservation and blackout protection), your battery’s capacity is 5.76 kWh. If your energy use is 4 kW (because, for example, you’re running your reverse cycle A/C), your battery will last less than 2 hours overnight – or any time after your panels stop producing.
You can check your energy consumption on the Plico app – if you are using around 4 kW and you continue to do so for 2 hours you will have used 8 kWh. You can see how this can quickly drain your battery.
2.1 Feel like your battery should be charging faster?
Your battery charging capacity, and indeed the amount of energy available to you from your solar pv production, is limited by the size of your inverter. Inverter capacity is measured in kVA – this is a measure of apparent power. In a 100% efficient system, 5 kVA = 5 kW. Most Plico systems come with a 5 kVA Smart Hybrid Inverter, which means it can convert around 5 kW of power to be used in the home at any given time (Hybrid inverters convert DC power generated by your panels or stored in your battery into AC power to use in the home).
If your home is drawing more than 5 kW of power, you will still require electricity from the grid. That said, it's rare for single-phase homes to draw more than 5 kW at any one time.
And similarly, the inverter cannot charge the battery at more than the highest charge rate of the battery. In the case of batteries used in the Plico system, this is no more than 4.6 kW. If the battery is being charged at its highest charge rate, then it is likely the inverter will be able to generate more than 5 kW as it doesn't need to 'invert' the 4.6kW going into to battery, as it's charged in DC. That's why while the battery is charging, the PV can sometimes generate more kW than the nameplate of the inverter.
There are also safety measures built into the batteries to protect them from large surges in power imports and exports.
2.2 Is your battery discharging to the grid when it should be powering your home?
There are also cases where your battery will discharge directly to the grid for short periods of time. This can happen when the AC load (energy use) in your home spikes and then drops off. The load of an appliance can be almost instantaneous, but a battery must ramp down slower, as it cannot switch on and off instantly. So, your battery meets the energy demand, however when it’s no longer needed (because the appliance has been turned off for example), the battery still needs to push the excess energy somewhere until it balances out – and that means it goes to the grid for this short period.
3.0 Use energy during the day
The best way to get longevity from your battery overnight is to use your energy during the day (as much as you can) - or during the solar window - when your panels are producing the most energy. That means heating your home before it’s dark and ensuring your home is well insulated so you can store this heat (much like your battery stores energy). Seal windows and doors and check your roof to see if you have good coverage of insulation. Heat loss through windows can be minimised by closing blinds and ensuring you have quality block-out window coverings.
You can also look for ways to minimise that afternoon surge of energy use. Try slow cooking meals or minimising the amount of appliances you need for meals (who doesn’t love a one pot wonder?). Use low lighting such as lamps and efficient LEDs and charge your devices earlier in the day then plug out and switch off.
The mornings can be a struggle in the colder months, not to mention trying to minimise your energy use until the sun comes up. The mornings are darker and colder, and you may have already depleted your battery overnight. Try to hold off on turning the heating on until your panels are producing. Any energy use you can delay in the morning means you’ll be drawing less energy from the grid. Remember to set your pool pump and irrigation (if you need it) to later in the day in winter to avoid energy use on those dark mornings.
And remember, the more efficient your appliances are, the more you can save with your solar + battery system. But of course, how and when we use the appliances in our home also makes a big impact.
Find out how you can save on your energy bills in spring.
4.0 Keep night usage to a minimum
It stands to reason that if you use more of your energy during the day, you will need less energy at night. If your home is heated a little earlier in the day, you can switch it off when the sun goes down. Warm clothing, hot water bottles and ugg boots certainly help! Or, if you really need that heating on to maintain comfort, ensure the thermostat is set to 18 – 20°C in winter and 24 – 25°C in summer.
It's important to note that the solar batteries in Plico systems are not designed to maintain an A/C running throughout the night. Especially after a day with cloud clover. Reverse cycle A/Cs are among the most efficient ways to heat your home, however they still use a substantial amount of energy. Remember, heating and cooling your home is around 40% of your home’s total energy use. If you have underfloor heating or other energy intensive systems, your energy use will be higher.
You can also reduce your night-time energy usage by turning off unnecessary lights and switching appliances off at the wall. You can even swap Netflix for a good old-fashioned book!
5.0 Monitor the battery
Keeping track of your energy use, solar production and battery status will also help you optimise your system. If you’re like some Plico members, you may already find you are ‘addicted’ to checking the app. If you’re a little less across what your system is doing, then you and your family might like to get into the habit of checking it regularly. This is the best way to know what the capacity of your battery is and modify your behaviour to suit.
Using the app will help you:
- See if you have battery charge left each morning
- See if your energy use is exceeding what your system is producing
- How much energy you are using over the week
- How much energy you are selling back to the grid
- Measure the energy use of your appliances
- Share your system performance with friends, family and social media network!
Note that the app provides a snapshot of what your system is doing. It is not 100% live and may, from time to time, show energy flow that doesn’t look right. For example, you may observe you are selling excess energy to the grid rather than charging the battery. Or, like in the example above, selling to the grid from your battery. This is the battery protecting itself and won’t last for too long.
If nothing else, you should view your Renewable Energy Meter in the app regularly; it shows the system’s impact on your energy consumption during the past 7, 30 or 90 days. If it falls below 60%, it’s worth reviewing your usage habits or your system size and settings.
And remember, you need to maintain an internet connection to enable you to monitor how your system is performing.
6.0 Maximise solar production
Your battery stores energy generated by your solar panels. Therefore, the more energy your panels can generate, the more likely you are to have a full battery when the sun goes down. Shading is the major impediment to the amount of energy your panels can generate. You can extend the time your panels are generating by removing anything that might cause shading. This includes aerials and satellite dishes, trees and other vegetation, as well as other structures. Plico panels use split-cell technology to minimise the impact of shading as much as possible, however one thin line of shading caused by an aerial can still put multiple panels out of action.
Of course, it may not be possible to remove everything that causes shading (if your neighbour’s two-story house for example) but there may be simple things you can move or remove completely to maximise your pv performance.
Shading can be more of an issue in the winter months because the sun is lower in the sky. If you like the tall trees around your home and are happy with your system’s performance in summer, then take this into consideration before doing anything drastic.
7.0 Switch energy plans
If you want to save more energy on your power bills and you use most of your energy before 3:00pm each day, you may want to consider switching to a Midday Saver Plan with Synergy and installing an advanced meter. This way, you can take advantage of lower rates during the day from 9am to 3pm (Super Off Peak – $0.08/unit) and overnight from 9pm to 9am (Off Peak - $0.22/unit). If you make the switch, note that your peak electricity charge (from 3pm to 9pm) will increase to $0.55/unit. There is also a meter upgrade or reprogramming fee of $96.50 and a supply charge of $1.20 per day.
Get in touch with us to find out if you’re a good candidate to switch plans or find out more at Midday Saver Pilot - Synergy.
8.0 Add more battery storage
Adding more battery storage isn’t always the answer to getting more battery life, but it can be if your circumstances have changed. If you’re not charging your battery each evening, then adding more storage won’t change this. If you are producing much more than you need - charging your battery and exporting a considerable amount to the grid, an additional battery may be worthwhile. However, there will be a cost for a battery upgrade.
If you want to find out if a battery upgrade can save you even more, contact us at email@example.com.
9.0 Add more solar panels
If you find your battery is not being fully charged each evening (across the year), then increasing production may be the solution. Adding extra panels will mean you can produce more during the day, perhaps for longer into the day, and have more excess to store in your battery. Determining whether extra panels would be beneficial depends on your energy use (remember your inverter can only push so much energy to your home and battery at any one time), available space on your roof or shed and the cost effectiveness of having a panel upgrade.
As always, we are here to help you make the right decision for you. Our team of experts can analyse your energy use, production and battery charging capacity and recommend the right course of action.
10.0 Reduce DoD and forgo extra blackout support
The battery DoD (Depth of Discharge), or maximum percentage of your battery's capacity, in all new Plico installations is set to 85%, unless otherwise requested. This maximum DoD allows you to squeeze the most out of your battery each night and increase its charging capacity. This means that in the middle of the night, however, if your battery is fully discharged and the grid goes down, you won’t have any power to your home. If your battery is set to 85% DoD, then you have the option to opt out of the extra 5% we set aside for extra blackout protection, however this is not recommended as sometimes the battery can dip below 10% and won't be able to start back up again.
As we outlined above, it is not possible to reduce the DoD of your PylonTech battery below 90% as this protects the battery life and means you get more longevity from your solar battery.
If this is something you want changed on your battery, please contact us at firstname.lastname@example.org.
While some things are out of your control when it comes to managing your Plico solar battery, there are plenty of things you can do to optimise it so you’re using less energy from the grid. Winter can be a tough time to be looking at solar and battery performance, so it’s important to take a holistic view of your solar + battery system over the entire year. Because once that sun starts shining again, you’ll be back up to self-producing 90, 95, 99% renewable energy!
If you have concerns about your system’s performance, please lodge a service request and one we will be in touch soon.