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Solar battery storage in Sydney: Compare prices & options

by Solar Choice Staff on November 9, 2016

in Batteries & Energy Storage,NSW

Solar battery storage is becoming an increasingly attractive and viable option for homes in Sydney, NSW. Fortunately, you can now compare battery storage options & prices from solar installers in Sydney with Solar Choice’s Battery Storage Quote Comparisons. What else do you need to know to make a decision about energy storage in Sydney?

Getting educated about energy storage in Sydney

Solar Choice has written extensively on the topic of energy storage in Australia and in NSW; now we’ll take a look at Sydney in particular. Making a decision about home energy storage in Sydney means first understanding the potential benefits of this increasingly popular technology, as well as some of the choices you’ll need to make in selecting the system that’s right for you.

Want to explore battery sizing options for your home? Check out our Solar & Battery Storage System Sizing & Payback Estimator Tool.

Sydney’s three energy storage customer categories

If you are considering an energy storage system in Sydney, then you probably fall into one of the following three categories: 1) You have a solar PV system and are receiving a generous solar feed-in tariff for exporting your solar energy to the grid under NSW’s Solar Bonus Scheme, 2) You have a solar system but don’t receive a feed-in tariff (only a voluntary ‘retailer contribution’), or 3) you have no solar system at all yet. Depending on which one of these situations you’re in, your energy storage needs will differ.

Category 1: Existing solar system, Solar Bonus Scheme feed-in tariff to expire at end of 2016

If you’re in category 1, you’re probably aware that your feed-in tariff payments will cease at the end of 2016, after which point you’ll be getting paid virtually nothing for your solar power. Once this happens, you’ll want to maximise your ‘solar self-consumption’. Energy storage can help you do this by allowing you to store your solar energy for after the sun has gone down. You’ll want an energy storage system sized to trap only the solar you don’t use. 

If you don’t know how much that is, you can look at your energy bill and subtract the amount of solar (in kWh) that you export to the grid from the amount of electricity that you consume. We should note that it probably won’t make sense for you to have your energy storage in operation until after the feed-in tariff payments cease – although you may want to have it installed before then.

Example: A home that uses about 10 kilowatt-hours (kWh) per day on average annually with a preexisting 2kW solar system, where most electricity is used during daylight hours (‘Double hump’ pattern, as explained in this article). 2kW systems were typical back when the Solar Bonus Scheme was still open to new entrants and solar panel prices were still high. But once the Solar Bonus Scheme ends, feed-in tariff payments will cease and this home will want to prevent its excess solar energy from going into the grid. Once this happens, on the average day, this home would be producing 3.5kWh more than it uses, so the goal would be to have a battery bank that could capture this. Assuming that the batteries selected have an overall storage efficiency of 95% and a maximum recommended depth of discharge (DoD) of 80%, about 5kWh of storage would be appropriate.

Sydney 2kW solar 5kWh storage example

Energy flows for Sydney home with 2kW solar system, 10kWh daily electricity usage (on average) and 5kWh of battery storage. With the battery storage, this home would utilise close to all of the electricity produced by the 2kW solar array. (Key: Grey shaded area is grid electricity consumption, orange shaded area is solar self-consumption, and shaded purple area is battery storage usage. The yellow line is solar system power output, while the purple line is battery state of charge – aligned with right axis. The blue bars represent solar into batteries, while the red bars represent solar into the grid.)

Category 2: Existing solar system, no feed-in tariff incentive

If you’re in category 2, you may already be looking to retrofit batteries to your system because any solar power you send into the grid is essentially wasted – you get paid only 6-8c/kWh (depending on your retailer). Batteries can help you prevent this from happening. You should be able to see on your electricity bills how much solar you export to the grid – you’ll want a battery bank that will be able to capture that amount. Since your payments are already low, now is as good a time as any to install batteries, provided you can find a good deal.

Example: A home with a 3kW solar PV system, using about 15kWh per day on the ‘Double hump’ usage pattern (described in more detail here). This home could be exporting around 7kWh of solar to the grid on the average day, and would want to capture as much of this as possible using batteries. Assuming 95% round-trip storage efficiency and 80% maximum recommended DoD, 7kWh of battery capacity would help the household meet this goal.

Sydney 3kW solar 7kWh storage

Energy flows for Sydney home with 3kW solar system, 15kWh daily electricity usage (on average) and 7kWh of battery storage. With the battery storage, this home would utilise close to all of the electricity produced by the 3kW solar array. (Key: Grey shaded area is grid electricity consumption, orange shaded area is solar self-consumption, and shaded purple area is battery storage usage. The yellow line is solar system power output, while the purple line is battery state of charge – aligned with right axis. The blue bars represent solar into batteries, while the red bars represent solar into the grid.)

Category 3: Solar system yet to be installed, no feed-in tariff available

If you are in category 3, you are probably in the market for a combined solar-plus-storage system. If you’re in this situation, you have a lot of flexibility in selecting a solar-plus-storage system (and you might want to read our article: How much battery capacity do you need?) If you can afford it and it makes financial sense for you, it may make sense for you to have a system installed as soon as you find a good deal.

Example: A Sydney home that consumes 20kWh per day on average throughout the year would like to reduce their grid reliance by as much as possible within a $10,000 budget (the typical amount a home would be willing to spend, according to a recent survey we conducted). Let’s start with a 3kW solar system for about $4,000 (on the low end of the spectrum according to our October 2016 PV Price Index); this would allow for about $6,000 to be spent on batteries. Assuming (optimistically) a battery storage price of about $1,200 per kWh, the home could afford about 5kWh of battery capacity (with 95% efficiency and 80% DoD). With this 3kW solar + 5kWh storage system, the home would only meet about 42% of its own electricity needs (and using on average about 72% of the solar produced). Payback periods are another question altogether – but indicative assessments would suggest 10+ years – which may cause this household to question whether it’s a good idea to invest in the battery portion of the system at this point.

Sydney 3kW solar 5kWh storage

Energy flows for Sydney home with 3kW solar system, 20kWh daily electricity usage (on average) and 5kWh of battery storage. The home would still be heavily reliant on the grid for electricity. (Key: Grey shaded area is grid electricity consumption, orange shaded area is solar self-consumption, and shaded purple area is battery storage usage. The yellow line is solar system power output, while the purple line is battery state of charge – aligned with right axis. The blue bars represent solar into batteries, while the red bars represent solar into the grid.)

Compare battery storage options in Sydney: Complete the Solar Quote Comparison request form to the right of this page.

© 2016 Solar Choice Pty Ltd

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