HEAT PUMP HOT WATER WITH SOLAR: THE ULTIMATE GUIDE FOR ADELAIDE & MELBOURNE
Tired of high energy bills? Discover why thousands of Australian homeowners in Adelaide and Melbourne are switching to Heat Pump Hot Water Systems — the smarter, more sustainable choice when paired with solar power.
Heat pump hot water systems are quickly becoming the go-to solution for efficient, eco-friendly hot water – especially when paired with solar energy. In the last year alone, installations of heat pump hot water systems in Australia jumped by 70%, thanks to improved performance and generous rebates.
Homeowners and facility managers (from suburban Adelaide to metropolitan Melbourne) are eyeing these systems as a replacement for ageing electric or gas heaters. This guide breaks down everything you need to know – how heat pumps work, why they're ideal with solar, what incentives are available, and how Jousto's smart Energy Hub can amplify your savings.
WHY HEAT PUMPS ARE THE FUTURE OF HOT WATER
MASSIVE ENERGY SAVINGS
Modern heat pump water heaters use up to 70% less electricity than traditional electric resistance systems. Instead of generating heat from scratch, they harvest ambient heat from the air to warm your water.
This high efficiency means lower energy bills – often reducing water heating costs by 50–70% compared to old electric or gas units. In real terms, many households see hundreds of dollars in annual savings.
STRONG ROI
Thanks to energy savings and rebates, a quality heat pump can pay for itself in as little as 3–5 years. Melbourne's climate, for instance, allows year-round efficient operation, and rebates can cut upfront costs by $1,000–$2,000.
Homeowners typically recoup their investment within a few winters of lower bills. In South Australia, bill reductions of ~18–30% are common when replacing old systems.
ECO-FRIENDLY PERFORMANCE
Every heat pump installed helps cut greenhouse emissions. By using renewable heat from the air, heat pumps slash carbon output versus gas burners or coal-powered electric tanks.
For environmentally conscious consumers – including community housing projects and NDIS facilities aiming for sustainability – this is a big win. Heat pumps also avoid gas combustion entirely, eliminating risks of gas leaks or toxic emissions.
WIDE ADOPTION & RELIABILITY
The technology is proven – over 150,000 units are installed across Australia, from homes to aged care centres, with that number growing fast. Premium brands offer long warranties (often 10–15 years on tanks).
Well-maintained units can last over a decade. Users on forums often ask if heat pumps last; the answer is yes – a lifespan of 10–15 years is typical, rivalling traditional heaters.
PERFECT FOR ELECTRIFICATION
As Australia moves towards full home electrification, heat pumps are a crucial component. They allow homeowners to eliminate gas connections entirely, creating an all-electric home that can be powered by renewable energy.
This transition is supported by government policies and rebates, making it financially attractive to switch from gas to electric heat pump systems as part of a broader sustainability strategy.
SMART INTEGRATION
Modern heat pumps can be integrated with home energy management systems like Jousto's Energy Hub. This allows for intelligent operation based on solar production, electricity prices, and household usage patterns.
The ability to time operation during periods of excess solar production or low grid prices maximises savings and minimises environmental impact, making heat pumps a smart choice for the connected home.
HOW HEAT PUMP HOT WATER SYSTEMS WORK
A heat pump hot water system works like "a reverse refrigerator." Instead of cooling air, it extracts heat from the air and pumps that heat into water:
- Evaporation: A fan draws in outside air over refrigerant coils. Even if the air is cool, the refrigerant absorbs its heat (heat pumps can pull useful energy from air as cold as -10°C in premium models).
- Compression: The refrigerant (now a warm gas) is compressed, raising its temperature significantly.
- Heat transfer: The hot refrigerant passes through a heat exchanger around the water tank, transferring heat to the water. The refrigerant cools and turns back into liquid, ready to repeat the cycle.
- Result: The water in the insulated tank heats up to the set temperature (typically ~60°C). This process is powered by electricity, but for every 1 kWh of electricity, a heat pump can deliver 3–5 kWh of heat to your water.
This Coefficient of Performance (COP) of 3–5 means free heat from the environment provides the majority of the energy.
The outcome? Lots of hot water for a fraction of the energy. For example, 1 kW of input can yield ~5 kW of heating – a 500% output – in top models. This efficiency holds especially well in mild climates like Adelaide and Melbourne, making heat pumps an excellent fit for both regions.
BENEFITS OF PAIRING HEAT PUMPS WITH SOLAR
One of the biggest advantages of heat pump systems is how seamlessly they integrate with solar PV panels. If you have solar (or plan to add it), a heat pump maximises your solar investment:
- Use solar power you'd otherwise export: Rather than send excess midday solar generation to the grid for a low feed-in tariff, you can run your heat pump to store that solar energy as hot water. Essentially, your water tank becomes a thermal battery – you're bottling sunshine to use for your evening shower.
- Reduce grid reliance: Running the heat pump during peak solar hours or when wholesale prices are low means you draw little to no electricity from the grid for water heating. This can drive your bills down further, especially in summer when solar output is high.
- Smart scheduling: Heat pumps can be set on timers or controlled via smart systems to operate when solar is available. Jousto's Energy Hub takes this to the next level by automating your heat pump to run at optimal times – for instance, when your solar is at peak or even during negative-price events on the grid.
- Eliminate gas entirely: For homes switching from gas, combining solar PV with a heat pump means you've now fully electrified hot water with zero on-site emissions. No more gas bills or the daily gas supply charge – just free or cheap solar-heated water.
MISCONCEPTION CLEARED
"I already have solar hot water, do I need a heat pump?"
Traditional solar thermal hot water systems use roof collectors and often have electric/gas boosters. They save energy, but heat pumps can actually be more efficient and flexible.
A heat pump doesn't require clear roof space or plumbing to the roof, and it works day or night (storing energy when it's cheapest). Many homeowners are now replacing old solar thermal systems with heat pumps for greater year-round savings, simplicity, and better integration with home energy management.
ADELAIDE VS. MELBOURNE: CLIMATE AND INCENTIVES
Both Adelaide and Melbourne see strong interest in heat pump hot water, but there are local nuances:
ADELAIDE (SOUTH AUSTRALIA)
Adelaide's Mediterranean climate (warm summers, mild winters) is ideal for heat pumps. Even in cooler months, daytime highs are usually sufficient for efficient operation. Quality heat pumps in SA operate effectively down to -10°C – and Adelaide rarely gets that cold.
South Australians also enjoy robust incentives: under the REPS (Retailer Energy Productivity Scheme) (formerly REES) and federal programs, you can get big discounts. The City of Adelaide, for example, offers rebates up to $1,000 for solar hot water heat pumps.
Combined with federal Small-scale Technology Certificates (STCs), total incentives can reach $2,000+ for eligible installations. The result? Many Adelaide homeowners replace old electric tanks for little out-of-pocket cost.
MELBOURNE (VICTORIA)
Melbourne's temperate climate includes colder winters, but modern heat pumps handle this well. It's true that cheap models struggle below ~5°C, kicking in an electric booster and losing efficiency. However, high-COP units (and CO₂ refrigerant models) thrive even in chilly conditions.
For Melbourne residents, the economic case is boosted by generous rebates: You can combine three different incentives – federal STCs (worth ~$600–$800), Victorian Energy Upgrades (VEEC, $420–$780), and Solar Victoria's heat pump rebate ($1,000) – for a total of up to $2,600 off.
This "double-dip" rebate opportunity in VIC is a major reason heat pumps are booming. With the rebates, many Victorians find a quality 250L–315L heat pump costs under $1,500 out-of-pocket.
INCENTIVES SNAPSHOT
In summary, both SA and VIC offer strong support:
- South Australia: Federal STC (~$700), SA state programs (up to ~$1,000 or more via REPS), plus City of Adelaide bonus ($500–$1,000) – combining to potentially $1,500–$2,000+ in aid.
- Victoria: Federal STC (~$700), VEEC (~$400–$800), Solar Victoria $1,000 – totalling up to $2,600 off your system. This often covers 40–60% of a mid-range system's cost.
Both regions also allow interest-free loans or financing on solar/energy upgrades in certain cases, which can further ease the upfront cost. Always check the latest local programs, as these incentives can update year to year.
COSTS AND SAVINGS: WHAT TO EXPECT
UPFRONT COST
Without any rebates, heat pump hot water systems typically range from about $2,000 to $5,000 for the unit itself (smaller 170L–200L units on the lower end, premium 300L ones on the higher end). Installation costs can add $600 to $1,400, depending on complexity.
- Swapping a similar electric tank in the same spot is straightforward, keeping install costs around the low end (~$700).
- Converting from gas to electric heat pump is more involved – it needs a new circuit from the switchboard and safe decommissioning of gas lines. This scenario may hit the higher install range (~$1,200 or more).
- Additional factors like difficult access, moving the unit's location, or upgrading old plumbing can add cost.
After federal STC rebates (which nearly everyone gets instantly as a discount), the average price for a heat pump upgrade in Australia is around $4,150 including basic installation. In SA and VIC, applying state rebates brings typical out-of-pocket costs to ~$1,500–$2,500 for many homeowners.
RUNNING COSTS
Here's where heat pumps shine. A family of four with a traditional electric water heater might spend $800+ a year on water heating. A heat pump could slash that by around 2/3.
In fact, data from Sustainability Victoria comparing water heater types showed heat pumps as the cheapest to run annually. By consuming ~70% less energy, many users save $300–$500 per year on energy bills just from hot water.
If you have solar and run the heat pump mostly on solar power, your effective hot water energy cost could drop to nearly zero on sunny days.
Example: One Reddit user in Melbourne noted their heat pump cut their peak electricity use dramatically, and with rebates the system cost was nominal. Similarly, a Whirlpool forum member in Perth calculated that even with conservative settings, a heat pump paid for itself in about 4 years via bill savings – making it absolutely "worth it."
MAINTENANCE AND LIFESPAN
Heat pumps are low-maintenance. They have a fan and compressor (like an AC unit) which should be kept clear of debris. Many have sacrificial anodes in the tank to check every few years (like any storage tank).
In general, they don't require frequent servicing. Warranties often cover 5+ years on the compressor and 10+ on the tank, indicating manufacturer confidence.
Over 10–15 years, you might replace a fan or sensor, but those costs are minor compared to the savings reaped.
FEATURED HEAT PUMP BRANDS
We supply and install premium heat pump hot water systems from leading manufacturers:
Compare models, check rebates, and find the perfect system for your home in just minutes.
🛒 Browse the full rangeJOUSTO'S SMART ENERGY HUB: THE GAME-CHANGER
All heat pump systems will save you money – but Jousto takes it further. Our Energy Hub technology acts as the intelligent brain of your home's energy. Here's how it amplifies the value of a heat pump hot water system:
- Automation for maximum savings: The Energy Hub connects to your heat pump and monitors your solar production and even the wholesale electricity market. It can automatically run your heat pump during times of cheapest power – for instance, when your rooftop solar is exporting or when grid prices drop mid-day.
- Wholesale energy integration: Unlike standard setups, Jousto leverages dynamic energy pricing. If you're on a plan like Amber Electric or similar, prices change half-hourly. Jousto's system will schedule your heat pump to run during negative or low-price periods.
- Holistic energy management: The Energy Hub isn't just for hot water. It also coordinates EV chargers, batteries, and other appliances. For a homeowner, this means your entire energy ecosystem is optimised.
- Monitoring & control: You get a user-friendly app/interface to see what's happening. You can set preferences – say, "always have water at 60°C by 6am" – and the system will work out the best times to run.
EXPERT INSTALLATION & SUPPORT
Jousto is not just selling a product; we deliver a service. Our team includes licensed plumbers and electricians (we do installations across SA, VIC, and beyond).
We ensure your old system is safely removed, the new heat pump is set up to code, and the smart controls are configured perfectly. Post-installation, we remain on call for support, and the Energy Hub can even enable remote troubleshooting or performance tweaks.
Why does this matter to you? It means when you choose Jousto, you're not only getting hot water – you're getting peace of mind that your hot water system is always running in the most cost-effective way possible. No other provider offers this bundle of top-tier hardware plus intelligent optimisation.
Imagine waking up knowing your hot water was heated with solar you'd otherwise waste, or with 3¢/kWh overnight wind power. That's Jousto's promise: hot water, smartly delivered.
SERVING ADELAIDE & MELBOURNE
We supply and install Heat Pump Hot Water Systems in Adelaide and Melbourne, with fast delivery and expert support across:
ADELAIDE AREAS
- Glenelg
- Norwood
- Prospect
- Morphett Vale
- Burnside
- And all surrounding suburbs
MELBOURNE AREAS
- Brighton
- Brunswick
- Dandenong
- Essendon
- Footscray
- And all surrounding suburbs
Wherever you are — we'll help you reduce bills, shrink your carbon footprint, and upgrade your hot water.
TOP 10 FAQ ABOUT HEAT PUMP HOT WATER
Here are ten frequently asked questions we often hear from Adelaide and Melbourne customers regarding heat pump hot water systems – along with concise answers:
Yes – thanks to big energy savings and rebates, heat pump systems are absolutely worth it. They use ~70% less power than old electric heaters, so you save on bills. Both SA and VIC offer incentives (up to $2k–$2.6k) that cut purchase costs.
In Adelaide's mild climate and Melbourne's well-supported market, a quality heat pump often pays for itself within 3–5 years. After that, it's money in your pocket every year.
They work by extracting heat from the air. A fan pulls in outside air, a refrigerant absorbs the air's heat, then a compressor concentrates that heat and transfers it to the water in the tank. It's the reverse of how a fridge cools.
Because they move heat rather than make it, they're super efficient – 1 unit of electricity can generate 3–5 units of heat in your water. Even in cold weather, there's enough ambient heat for the system to work (down to around -10°C for good models).
Yes, absolutely. In fact, pairing with solar is ideal. You can set the heat pump to run during the day to use your solar PV's excess energy. This means your hot water is heated "for free" by the sun.
Jousto's Energy Hub can automate this, turning on the heat pump exactly when your solar output is highest. With solar, many customers find their electric bill for hot water drops to near zero on average. It's a perfect combination for reducing grid usage and maximising solar self-consumption.
There are generous rebates in Australia:
- Federal STC incentive: Worth roughly $600–$800 off upfront (applied as a discount by installers in most cases).
- South Australia: Under REPS, many households qualify for additional discounts (often $500–$1,000 value), and City of Adelaide residents get up to $1,000 rebate.
- Victoria: You can stack three incentives – STC, Victorian Energy Upgrade (VEEC ~$500), and Solar Victoria's $1,000 rebate – totalling up to $2,600 in rebates.
These significantly lower the cost of a heat pump system. Check local eligibility (often if replacing an electric unit, you qualify; replacing gas has slightly different rules). Jousto helps clients navigate and claim all applicable rebates.
After rebates, most people pay around $1,500 to $3,000 out-of-pocket for a good system, including installation. The exact cost depends on the unit size/brand and installation complexity.
For example, a 250L unit might be $2,500 for the system and $800 for install = $3,300, minus say $1,500 in rebates → ~$1,800 net cost. Without any rebates, a high-end system plus install could be around $5,000.
The average national installed cost is ~$4,157 before state rebates. It's higher than a basic electric heater, but remember the running costs are far lower – so the investment pays back over time. Jousto provides upfront quotes showing the full price and then any rebates you're entitled to, so you see the final cost clearly.
Yes, modern heat pumps are designed to work year-round. In winter, they do run longer and a bit less efficiently (because the air is colder), but they will still heat your water.
For instance, many units that have a COP of 4 in summer might drop to COP 2–3 in cold winter nights – meaning they're still 200–300% efficient (2–3 times more efficient than a traditional heater).
In places like Melbourne where winter nights can approach 0°C, it's important to get a unit with good low-temp performance. Some models have a built-in electric booster that kicks in only if needed on the chilliest nights, so you never go without hot water.
As long as your unit is sized right, you won't notice any difference in availability of hot water in winter – just possibly a slight uptick in electricity use compared to summer (still much less than an electric tank would use).
They're pretty quiet. The sound comes from a fan and compressor, similar to a small air conditioner. Typically, noise levels range from 37 dB to 50 dB. 37 dB is very quiet – like a whisper or a refrigerator humming in the next room. 50 dB is a bit louder, like moderate rainfall.
Most units will be closer to the 45 dB mark. In practice, customers rarely complain about noise. If the unit is outside or in a garage, you might not hear it at all indoors. If near a bedroom window, you might hear a faint hum when it's running – but remember, it doesn't run constantly; once the water's heated, it turns off.
If noise is a concern, Jousto can recommend ultra-quiet models and placement that minimises any disturbance.
On average about 10 to 15 years, which is similar to or a bit longer than a conventional electric or gas tank. The tank portion is like any other hot water tank (glass-lined steel) and often comes with a 10-year warranty. The heat pump mechanism (compressor, etc.) might have a 5-year warranty on parts.
With proper maintenance (flushing the tank if needed, replacing anodes every few years in hard water areas), some heat pumps have been known to last 15+ years. It's good to check warranty terms of the brand you choose: e.g., Sanden offers 15 years on the tank and 6 years on the compressor, which indicates the expected longevity for high-end systems.
Jousto only installs reputable brands with solid support, so you're covered long-term.
Yes, definitely. Converting from gas to a heat pump is a common upgrade, especially as homes move towards all-electric setups. The installer will safely cap off the gas line and you might even be able to remove the gas meter eventually (saving on supply charges).
The main difference for install is running an electrical circuit to power the heat pump – Jousto handles the necessary electrical work with licensed electricians. Once installed, you'll enjoy not just lower energy bills but also the elimination of gas appliance maintenance and the improved safety of having no gas combustion in the home.
Plus, many state rebates (like in VIC) apply a bonus when switching from gas to efficient electric, because it helps reduce emissions. So you get help with the cost. In short, gas to heat pump is a wise switch that many are doing in Adelaide and Melbourne.
Jousto combines expert installation with smart technology that others don't offer. When you get a heat pump hot water system from Jousto, we don't just set and forget it – we integrate it with the Jousto Energy Hub, which intelligently controls when the heat pump runs to maximise use of solar or off-peak power.
No other provider in SA or VIC is currently offering this level of automation for hot water. Essentially, with Jousto you get:
- Top-quality heat pump unit (we'll help choose the right brand/model for you).
- Professional installation by our team (plumbing and electrical included, no fuss).
- Smart Energy Hub controller that links your heat pump to your solar system or tariff data, optimising your energy use in real-time.
- Ongoing support and monitoring – we ensure your system runs smoothly and you get the savings promised.
This means a Jousto-installed system could save you more money over its life than a standard install, due to the smart scheduling. We turn your hot water system into an active part of your energy-saving toolkit, not a passive appliance. That's the Jousto difference – we marry efficiency with intelligence for unbeatable results.
READY TO UPGRADE YOUR HOT WATER SYSTEM?
Join thousands of satisfied customers in Adelaide and Melbourne who are saving money and reducing their carbon footprint.
By covering all these aspects – from technical know-how to financial incentives and smart integration – this guide equips you with the knowledge to make an informed decision on heat pump hot water in Adelaide or Melbourne.
Heat pump hot water systems are the future of efficient home energy, and with Jousto's help, you can make that future a reality today. Here's to endless hot showers, dramatically lower bills, and a more sustainable home!
Solar Panel & Battery Sizing Guide for Australians
Australia’s sunny climate, combined with rising electricity prices and growing environmental awareness, has created the perfect conditions for homeowners to invest in residential solar panel and battery systems. But while going solar is a smart move, determining the right size for your system is critical to maximizing benefits—both financially and environmentally.
This guide is designed to walk you through the most important considerations when sizing your solar and battery system. Whether you're aiming to cut your power bills, reduce grid dependence, or boost your home’s value, this resource offers an unbiased, data-driven path to help you make the best decision.
Why System Sizing Matters
A solar system that’s too small might not generate enough energy to meet your household needs. On the flip side, an oversized system can lead to unnecessary costs and underused capacity. The right system size is one that perfectly aligns with your current and future energy use, fits your property’s physical characteristics, and supports your long-term financial and lifestyle goals.
Step 1: Understand Your Energy Consumption
The most critical input when sizing a solar panel system is your actual energy usage. Start by reviewing your past electricity bills—ideally for the last 12 months. This will help you calculate:
Monthly average usage (kWh)
Daily energy demand
Seasonal variations (e.g., more cooling in summer, heating in winter)
For the most accurate picture, request interval data from your energy provider or access it via your smart meter dashboard. This data reveals when you use electricity throughout the day and whether you’ll benefit most from solar energy during daylight hours or from storing power for use at night.
Step 2: Consider Usage Patterns and Future Growth
Energy usage isn’t static. Households often see increased energy demands due to:
Adding air conditioning systems
Buying electric vehicles (EVs)
Installing heated pools or spas
Expanding family size or adding home offices
Anticipating these changes ensures your solar and battery system is future-proof, helping avoid costly upgrades later on.
Step 3: Maximize Daytime Self-Consumption
Solar panels produce the most energy when the sun is shining. If your household uses most of its electricity during the day, you’ll naturally self-consume a larger portion of your solar power, which increases ROI. If your usage peaks at night, consider integrating battery storage to capture excess solar power and use it after sunset.
This is especially important if feed-in tariffs in your area are low. It's generally more economical to consume your solar energy than to export it to the grid.
Step 4: Evaluate Roof Size, Orientation, and Shading
Physical space is another critical determinant of system size. Here’s what to assess:
Available roof area: A typical residential panel is ~1.7m². Calculate how many can fit on your unshaded, north-facing roof sections.
Orientation: In Australia, north-facing panels provide the highest yield. East- or west-facing can also be viable but may generate less energy overall.
Tilt: Optimal angles typically range from 15–35 degrees. Too flat (<10°) may reduce performance.
Shading: Trees, chimneys, and nearby buildings can decrease output. Use tools like SunSPOT to evaluate shading impacts.
Step 5: Consider Regional Climate and Sunshine Hours
Solar performance varies by location. For example, systems in Brisbane or Perth may produce more electricity than identical systems in Hobart or Melbourne due to higher sunshine hours.
Use data from the Bureau of Meteorology to understand your area's average daily solar exposure. As a rough benchmark, each kilowatt (kW) of panels can generate about 4 kWh/day, but that number will shift depending on your local climate.
Step 6: Budget, ROI, and Government Incentives
Solar costs in Australia vary, but general pricing falls between:
$4,000–$5,500 for 3 kW systems
$6,000–$9,000 for 6.6 kW systems
$10,000–$13,000 for 10 kW systems
Key financial considerations include:
Payback period: How long it takes for savings to cover your system cost
STCs: Small-scale Technology Certificates can reduce upfront costs significantly
State rebates: Vary by region—check with your local government
A well-sized system delivers a solid return on investment in 4–6 years, depending on usage and tariff structures.
Step 7: Understand Electricity Tariffs and Feed-In Rates
Electricity plans affect solar ROI. If your plan includes:
Flat rates: Simplifies sizing, focus on total daily usage
Time-of-Use (TOU) rates: Involves peak/off-peak pricing—battery storage becomes more valuable
Feed-in tariffs: Typically lower than grid prices; storing solar energy is more cost-effective than selling it
Designing your system to minimize reliance on grid electricity during peak times can result in significant long-term savings.
Step 8: Comply with Local Network Constraints
Australia’s energy networks often impose limits on how much solar you can install or export:
Single-phase connections may limit inverter size to 5 kW
Export limits may apply above certain thresholds
Approval processes are often required for systems over 5–10 kW
Speak with your installer or network provider to understand local rules before committing to a system size.
Sizing Your Solar System: Key Calculations
Method 1: Daily Usage / Daily Sunlight Hours
Use this simple formula:
Required Solar Size (kW) = Average Daily Usage (kWh) / Average Daily Sunlight Hours
Example: 30 kWh/day / 5 hours = 6 kW system
Add a buffer of 20–25% to account for losses and inefficiencies. A 6 kW system might become 7.2 kW with this margin included.
Method 2: Roof Area and Panel Specs
Standard panel: 1.7m², 400W capacity
30m² sunny roof = ~17–18 panels
18 x 400W = 7.2 kW system
If space is limited, opt for high-efficiency panels to maximize output in a smaller footprint.
Online Calculators to Assist You
Tools like SunSPOT (developed by Australian engineers), CHOICE Solar Estimator, and SolarQuotes.com.au offer valuable simulations.
They help estimate:
System size
Output based on postcode
Savings and payback time
Use them to cross-verify your findings, but always follow up with a qualified installer for a site-specific assessment.
Sizing Your Battery Storage: Key Factors
1. Backup Power Requirements
Decide what appliances you want to run during blackouts (e.g., fridge, lights, modem). Calculate total power (Watts) and usage hours to determine the needed battery capacity in kWh.
Example: 100W fridge + 50W lighting for 6 hours = 0.9 kWh. Factor in battery depth of discharge (~80%), so usable capacity = 1.125 kWh.
2. Self-Consumption Goals
If you use 10 kWh of electricity at night, your battery should store at least that amount of usable energy. This allows you to operate independently from the grid after dark.
3. Time-of-Use (TOU) Tariffs
Batteries can be charged during off-peak hours and used during peak demand, saving you money. Estimate your peak hour usage and match your battery size accordingly.
4. Matching Battery to Solar Array Size
Your battery should match or slightly exceed your solar generation surplus. For instance:
6.6 kW solar system → ~25–28 kWh/day
Assume 50% exported = 12–14 kWh → choose a 10–13 kWh battery
Common pairings:
6.6 kW system + 10 kWh battery
10 kW system + 13–15 kWh battery
Battery Sizing Tools and Guidance
Websites like SolarCalculator.com.au and SolarQuotes.com.au also offer battery estimators. Input your solar system size, usage goals, and budget to get a suggested battery capacity. These tools provide a great starting point, but a local installer will provide the most accurate guidance.
Direct Tools and Calculators from Jousto
Jousto simplifies solar decision-making by offering direct integration with SunSPOT, Australia’s most trusted solar and battery sizing tool.
What is SunSPOT?
SunSPOT is a free, not-for-profit solar and battery calculator created by Australian photovoltaic engineers. It evaluates your:
Location and sunshine hours
Household energy usage
Roof orientation and shade
Tariffs and feed-in rates
How Jousto Uses It
By embedding SunSPOT into its platform, Jousto helps homeowners estimate system size, savings, and battery ROI—with total transparency. It’s ideal for comparing battery options, running what-if scenarios, and calculating payback periods.
Learn more or try it out at: jousto.com.au
Independent Solar & Battery Design
What sets truly optimized solar systems apart is not just the tech—it’s the approach.
Independent design means building a system that’s tailored to your needs, not influenced by vendor relationships or sales quotas. It ensures:
Objective component selection (panels, inverters, batteries)
Design flexibility for future upgrades
Performance that matches your household’s real-world needs
Financial modeling that factors in rebates, TOU tariffs, and more
By prioritizing you, independent solar design results in smarter, more cost-effective solutions.
Conclusion: Make Your Solar Investment Count
Sizing your home solar and battery system correctly is more than a technical task—it’s a strategic decision. By considering your energy usage, roof and climate factors, tariff structures, and long-term goals, you can invest with confidence.
Remember:
Start with your own data
Use reputable tools like SunSPOT
Consult with qualified, independent experts
Focus on value, not just system size
Take the Next Step
💡 Ready to size your system the smart way?
Use the free SunSPOT calculator via Jousto and get a detailed, unbiased system estimate today.
Empower your energy future—on your terms. by clicking here: https://jousto.com.au/
