10kW Solar System Cost NSW 2026 - Get Free Quotes

10kW System Costs in NSW

A 10kW system installed in New South Wales runs $7,000 to $12,000 after the federal rebate has been applied at the point of sale. Budget packages using tier two panels and a basic string inverter sit at the bottom of that band, mid range systems with tier one panels and an established inverter brand occupy $8,500 to $10,500, and premium configurations with microinverters or panel level optimisers reach the top. The spread reflects component quality and warranty backing rather than generation capacity, since all three will be rated at the same 10 kilowatts. Broader system pricing across sizes is covered at solar panel installation costs.

The rebate is almost always deducted before you see the number. A 10kW system attracts roughly 140 small-scale technology certificates depending on the installation year and zone, worth $3,500 to $4,500, and reputable installers quote the net figure rather than advertising a gross price and applying the discount later. If a quote looks dramatically cheaper than the rest, check whether it is a net or gross figure before concluding anything. How the scheme works in detail is set out at solar rebate guidance. Reading a quote for its certificate count, not its dollar figure, is the quickest way to check whether two proposals sit on the same basis.

Panel count matters less than most people expect. A 10kW array using 440 watt panels needs around 23 modules, while higher output panels reduce that count and the roof area required, which matters on a complicated roof and not at all on a simple one. What the panel count does affect is labour, since more modules means more mounting and more cabling. Ask for the panel model and the number of modules, since a headline capacity figure on its own tells you very little. Panel efficiency has improved enough in recent years that a 10kW array now occupies noticeably less roof than the same capacity did five years ago.

Site conditions move the price more than brand choice in many cases. A two storey house, a tile roof requiring careful handling, a long cable run from array to switchboard or a switchboard needing upgrading all add cost that has nothing to do with the equipment on the roof. These are the items that separate two quotes for identical hardware. Where nobody has inspected the site or worked through a detailed satellite assessment, treat the figure as an opening estimate. Two identical systems on identical roofs a suburb apart can differ by more than a thousand dollars purely on access and cable run.

Export Limits and Network Approval

The single most important number in a 10kW proposal is not the price but the export limit your distributor will approve. Network businesses cap how much power a property can send back to the grid, and those caps vary by area, by supply type and by the capacity of the local network, entirely independently of what your system can generate. A 10kW system on a five kilowatt export cap still generates 10 kilowatts, but the surplus above the cap is curtailed, never sold. That changes the financial case substantially.

Single phase properties are the ones most commonly limited. Many distributors apply a lower export allowance to single phase supply than to three phase, which is why a three phase upgrade at $2,000 to $4,500 sometimes appears in a 10kW quote and sometimes pays for itself. Whether it does comes down to how much of your surplus would actually leave the property instead of being used inside it. Have the installer model both scenarios before you decide. Distributors publish their connection policies, and a reputable installer will point you at the relevant document instead of talking in generalities.

Approval is the installer's job but the outcome is yours to verify. A competent installer applies to the distributor before installation and confirms the approved capacity and export limit in writing, and that document is the one to ask for. Systems installed without approval, or beyond an approved limit, create real problems with compliance and with connection. Never let an installation proceed on a verbal assurance that approval will follow.

Export limiting is a legitimate engineering solution and nothing has gone wrong when it applies. Where a distributor approves a 10kW system with a capped export, the inverter is configured to limit what it sends to the grid while still supplying the house freely, which means self-consumption is unaffected. Understanding that distinction is what makes a capped system worth installing for the right household. Feed-in arrangements and what surplus actually earns are covered at solar feed-in tariff guidance. Curtailment is invisible day to day. The system quietly produces less than it could, and nothing on the monitoring flags it as a problem.

What the Price Includes

A complete 10kW installation covers the panels, the mounting system, the inverter, all direct current and alternating current cabling, isolators, the meter arrangement and the network application. It should also include compliance certification, commissioning and handover of the monitoring platform, along with the paperwork required for the rebate claim. Anything excluded from that list belongs in writing on the quote, before anyone gets on the roof. Ask for the exclusions as directly as you ask for the inclusions. Getting that document before installation day is the difference between a system that connects cleanly and one that becomes an argument.

Mounting hardware is where quiet cost cutting happens. Rail, brackets and roof penetrations sit in the weather for decades and a corrosion resistant system properly flashed is what keeps a roof watertight, particularly in coastal areas. Cheaper mounting is rarely visible in a quote and is very visible in year eight. Ask what mounting system is specified and whether it suits your roof material.

Switchboard work is usually an addition the headline price does not cover. Older switchboards frequently need upgrading to accept a solar circuit safely, and where that is required it is real electrical work carrying a real cost. A quote that makes no mention of the switchboard on an older home is probably assuming it is fine. Have the installer confirm they have looked at it.

Meter reconfiguration falls to your retailer once the system is commissioned. After installation the meter has to be changed or reprogrammed to record export, and that process runs on the retailer's timetable, not yours, and can take weeks. Your system operates during that period but export may not be credited. Build the delay into your expectations, since it is a queue and not a fault. Corrosion rated fixings cost a fraction more at purchase and are the single most common thing quietly downgraded on a cheap quote.

Warranties come in three separate parts that are easily confused. Panel product warranty, panel performance warranty and inverter warranty are distinct, and the workmanship warranty from the installer is a fourth. Get all four stated in writing with their terms, since the strength of the installer's own warranty is usually the most useful indicator of quality. Inverter specifics are covered at solar inverter installation costs. Anything needing a licensed electrician beyond the solar circuit itself should surface during the assessment visit.

The Federal Rebate

The federal small-scale renewable energy scheme creates certificates based on system size, location and the year of installation. A 10kW system in New South Wales generates roughly 140 certificates, and their value fluctuates with the certificate market, which is why the rebate is quoted as a range and not a fixed figure. Installers assign the certificates and apply the value as an upfront discount. That is why the price you are quoted is already net.

Certificate volumes decline each year as the scheme winds down toward its end date. Each January the number of certificates a given system attracts drops, which slightly increases the net cost of an identical installation. That creates a mild incentive to install early in a calendar year. It is a modest factor, and no reason to rush a decision. That said, an installer unable to inspect beforehand should at least state a provisional allowance and say so plainly.

Eligibility depends on using accredited equipment and an accredited installer. Panels and inverters must be on the approved product list and the installation must be signed off by a Clean Energy Council accredited installer, and installations failing either test cannot claim certificates. This is one of several reasons accreditation is not optional. Verify the accreditation yourself, because a logo in a brochure means nothing.

State level incentives change more often than the federal scheme. Programmes covering batteries, low income households and specific regions come and go, and eligibility conditions vary considerably between them. Current New South Wales government programmes are published through service.nsw.gov.au. Check what is on offer at the time you are buying, since last year's information is frequently out of date. Keeping a copy of the certificate assignment paperwork is worthwhile, since it is the record of what was claimed on your behalf.

Production Expectations

A 10kW system in New South Wales produces 35 to 45 kilowatt-hours on a typical day across the year. That figure is an annual average, not a daily guarantee, and it assumes reasonable orientation and minimal shading, so a compromised roof produces meaningfully less. North facing arrays produce the highest total, while east and west splits produce slightly less overall but spread generation across morning and afternoon. Which is better depends entirely on when your household actually uses power.

Seasonal variation is larger than most people anticipate. Summer output can exceed 50 kilowatt-hours daily while winter drops to 25 or lower, and cloudy weeks in June bear little resemblance to clear weeks in December. Averaging across the year is the only sensible way to assess a system. Judging performance from a single week in either season leads to the wrong conclusion. Certificates are created and traded through a federal register, so their value moves with market conditions instead of sitting fixed.

Shading affects output disproportionately on string inverter systems. A single shaded panel can drag down an entire string, which is why homes with trees, chimneys or neighbouring buildings often benefit from microinverters or optimisers despite the additional cost. A good installer picks up shading during assessment, well before commissioning. Ask specifically what the shading analysis showed.

Panels lose a small amount of output every year as a matter of physics. Performance warranties guarantee around 85 percent of original output at year 25, which means a system installed today still produces usefully into the 2050s. That gradual decline is entirely normal. Sudden drops are the ones worth investigating, and diagnostics are covered at solar panel repair costs. Orientation is locked in the moment the panels are fixed to the roof, so the design conversation carries more weight than any component choice.

Self Consumption and Returns

The economics of a 10kW system depend almost entirely on how much of its output you use yourself. Power consumed on site displaces electricity you would have bought at the retail rate, while surplus exported earns a feed-in tariff that is a fraction of that rate. The gap between those two numbers is where the payback comes from. A household that uses half its generation does far better than one exporting most of it.

Payback periods of three to five years are achievable but not automatic. Reaching the shorter end requires genuinely high daytime consumption, which usually means a pool pump, ducted air conditioning running through summer afternoons or an electric vehicle charged at home during daylight. Households that are empty on weekdays and export most of their generation should expect the longer end. Model your own consumption, since a generic payback claim is worth very little. An installer who quotes a firm daily figure without ever asking about your roof orientation is working from a template.

Shifting usage into daylight hours is the cheapest way to improve returns. Running the dishwasher, washing machine, pool pump and hot water on timers during the middle of the day converts exported surplus into avoided purchases, and it costs nothing beyond changing habits. This single adjustment often improves the financial outcome more than upgrading components would. Start with the appliances that run on a timer already.

Electric vehicle charging is the strongest case for a system this size. A vehicle charged at home during daylight absorbs a large share of the surplus at full retail value, which transforms the return on a 10kW array. Households planning a vehicle within a few years are usually better off sizing for it now, since upgrading later costs more. Charger integration is covered at solar EV charger installation costs. Retailers reset their offers regularly, so the plan comparison is worth repeating each year.

Who a 10kW System Suits

A 10kW system suits households with genuinely high daytime consumption, and floor area alone is not the qualifier. Four or more occupants, a pool, ducted air conditioning and electric hot water together create the load profile that justifies this capacity. A three bedroom home with two occupants at work all day rarely does, regardless of roof area. How and when a household uses power tells you far more than its floor area does.

Swimming pools are among the clearest indicators. Pool pumps run for hours during daylight and are a substantial, predictable, shiftable load that a large array covers neatly. A household with a pool and ducted cooling is close to the ideal candidate for this size. Both loads peak precisely when the panels are producing most. Retailers publish their rates openly, so the comparison is straightforward once you know roughly what proportion you will export.

Home based work has shifted the calculation for many households. A house occupied through the day with computers, cooling and appliances running consumes far more daytime power than the same house did when everyone left at eight. If your household pattern changed in recent years, your consumption profile likely changed with it. Look at recent bills, because assumptions carried over from several years ago are often well out of date.

Planning matters as much as current usage. A household intending to add a pool, replace gas appliances with electric or buy an electric vehicle within a few years is sizing for a future load and not a present one, and that is a reasonable basis for going larger. Adding capacity later is possible but rarely as economical as installing it at once. Upgrade paths are covered at solar system upgrade costs. A pool pump alone can account for a substantial share of a household's daytime draw, and pool owners consistently see the strongest returns as a result.

Roof and Switchboard

A 10kW array needs meaningful roof area, 45 to 55 square metres depending on panel efficiency. That means usable area on suitable orientations, not total roof area, and vents, skylights, chimneys and hips all reduce what is actually available. Complicated roofs frequently cannot accommodate a full 10kW on the best facing planes. An honest installer will say so instead of scattering panels across poor orientations to hit a number.

Assess the roof condition before any panels go up. Panels last 25 years and a roof needing replacement within ten creates an expensive removal and reinstallation, so addressing roof condition first is far cheaper than dealing with it later. This is particularly relevant on older tile roofs. Ask the installer to comment on roof condition during the site assessment. Households that electrify progressively often find the system that looked oversized in year one is comfortably matched by year four.

Roof material changes both method and cost. Tile needs careful handling and the right tile hooks, metal roofs use clamps that are generally faster and cheaper, and slate or heritage roofing needs specialist attention. Each has its own mounting method and using the wrong one causes leaks. Confirm the installer has worked on your roof type before.

Switchboards on older homes commonly need work. Ceramic fuses, no residual current device protection or simply no spare capacity all require rectification before a solar circuit can be added safely, and that cost belongs in the quote rather than appearing as a variation on installation day. An installer who has not inspected the switchboard cannot know. Push for that inspection before accepting a fixed price. Roof replacement while panels are installed costs far more than doing the roof first, so the sequencing question is worth settling early.

Battery Readiness

A 10kW system generates enough surplus to make a battery genuinely useful, which is not true of smaller arrays. Storing 10 to 15 kilowatt-hours of afternoon surplus for evening use converts exported power earning a low tariff into avoided purchases at the retail rate. Whether that arithmetic works depends on battery cost, tariff rates and your evening consumption. Run the numbers on your own bills, since generic cases rarely resemble anyone's actual household.

Battery ready is a phrase worth pinning down. It sometimes means a hybrid inverter capable of accepting a battery directly, sometimes only that space and cabling have been allowed for, and the two involve quite different costs when the battery eventually arrives. Ask precisely what is meant when an installer uses the term. Get the answer written into the quote. On a complicated roof it is worth asking whether a slightly smaller array on good orientations would outperform a nominal 10kW spread across poor ones.

A hybrid inverter costs more upfront and saves money later. If a battery is likely within a few years, specifying a hybrid inverter now avoids replacing a perfectly good string inverter at battery installation. If a battery is genuinely unlikely, the premium is wasted. Answer that honestly rather than optimistically, and current pricing sits at solar battery storage costs.

Backup during outages is a separate feature from storage. Many batteries do not supply the house during a grid outage unless specifically configured with backup capability, which requires additional hardware and wiring. Households buying a battery primarily for outage protection need to specify that explicitly. Confirm it in writing, since it does not come as standard. Battery pricing has moved considerably in recent years, so figures more than a year old are worth rechecking before deciding.

Comparing System Sizes

A 6.6kW system remains the most common residential size in New South Wales and suits typical household consumption well. It costs substantially less, fits comfortably on most roofs and rarely encounters export limit complications. For households without a pool, ducted cooling or an electric vehicle it is frequently the better financial choice. Comparative pricing is set out at 6.6kW solar system costs.

The cost per kilowatt falls as system size rises. A 10kW system costs less per kilowatt installed than a 6.6kW one because labour, scaffolding, cabling and the network application are largely fixed regardless of panel count. That efficiency is the argument for going larger where consumption justifies it. It is not an argument for oversizing a system that will export most of its output at a low tariff. Retrofitting backup capability after the fact is possible but costs considerably more than specifying it at installation.

Going beyond 10kW moves a residential installation toward commercial territory. Larger systems face different network requirements, sometimes need different metering and may cross thresholds that change the approval process entirely. That step up is worth understanding before assuming bigger is simply better. Larger installations are covered at commercial solar installation.

Oversizing the array relative to the inverter is standard practice, not a trick. Panel capacity slightly above inverter capacity captures more energy across the year because panels rarely produce at their rated output, and the practice is permitted within defined limits. A quote showing 13kW of panels on a 10kW inverter is normal. Ask the installer to explain the ratio if it is not clear. Distributors assess inverter capacity, which is what puts that ratio on the approval paperwork.

Installation Process

Installation of a 10kW system takes one to two days on site. A crew installs mounting rails, lays and secures panels, runs cabling to the inverter location, mounts the inverter and connects to the switchboard, with commissioning and testing at the end. A larger crew compresses that timeline without changing the work itself. Weather and roof complexity are the usual reasons a job runs longer.

Most of the elapsed time sits in that preparation, well before anyone arrives with panels. Site assessment, system design, network application, approval and equipment ordering all happen first, and the elapsed time from signing to installation is commonly several weeks. Approval is usually the longest element. Ask for expected timing at each stage instead of one completion date. For most households the practical question is not whether bigger is better but whether the additional capacity will actually be consumed.

Work at height on a roof carries genuine safety obligations. Fall protection, edge protection and proper access are all mandatory, and an installer working from a ladder alone on a two storey roof is not complying. Work at height requirements in this state are administered by safework.nsw.gov.au. A crew that takes safety seriously generally takes the rest of the work seriously too.

Commissioning and handover are the parts most often rushed. A proper handover includes demonstrating the monitoring platform, explaining what normal output looks like across seasons, providing all warranty documentation and supplying the compliance certificate. Without that certificate you cannot demonstrate a compliant installation. Do not consider a job finished until the paperwork is in your hands. Scaffolding on a two storey installation is a legitimate line item rather than padding, and its absence from a quote is worth querying.

Maintenance and Monitoring

Solar systems need little maintenance but they are not entirely hands off. Rainfall handles most cleaning in New South Wales, though coastal salt, agricultural dust and bird activity all justify periodic attention, and an annual clean and inspection costs $150 to $350. Whether that is worth it depends heavily on your location. Cleaning specifics are covered at solar panel cleaning costs.

Monitoring is the maintenance that actually matters. Every modern system reports output, and checking that data occasionally is how a failed panel, a tripped isolator or a declining inverter gets noticed before it costs months of generation. Systems fail quietly, with nothing to bang or smoke and nothing obvious to notice. Set a reminder to look at the numbers each month. Rain delays are normal in this work, since neither roof work nor electrical connections should proceed in wet conditions.

Inverters are the component most likely to need replacement within the system's life. String inverters commonly carry five to ten year warranties against 25 years on panels, which means a replacement partway through is a realistic expectation and not a sign of failure. Budgeting for it avoids an unwelcome surprise. Extended inverter warranties are sometimes worth the premium.

Comparing output against the same month last year is the simplest diagnostic available. A meaningful drop with no change in shading or weather points to a fault worth investigating, well beyond normal degradation. This takes a few minutes and catches most problems early. Keep the first year of data as your baseline. Salt exposure extends well inland of the beach itself, so coastal specification is relevant across a broader area than people assume.

Sydney Metro Costs

Sydney has the deepest installer market in the state, which keeps 10kW pricing competitive and makes gathering three comparable quotes straightforward. Equipment prices are essentially national since panels and inverters move through national distribution, so the variation across the city sits in labour, access and roof type rather than in hardware. Two storey homes, tile roofs and difficult access are what move a Sydney quote around, far more than the postcode does. Getting three quotes from installers who have each physically assessed the roof is realistic in this market and worth insisting on.

Export limits vary noticeably across the Sydney network area. Different distributors service different parts of the city and their export policies are not identical, so a neighbour's experience in another suburb is not a reliable guide to yours. Established areas with older infrastructure are more likely to be constrained. Get your own address assessed, because anecdote from another suburb is not evidence. Most monitoring platforms will send alerts if configured, which removes the need to remember to check manually.

Coastal suburbs justify closer attention to mounting hardware. Salt exposure accelerates corrosion in fixings and rails, and specifying components rated for a coastal site is a small upfront premium against a large future problem. This applies well inland of the beach itself. Ask what corrosion rating the mounting system carries.

Heritage conservation areas can impose panel placement conditions. Some councils restrict visibility from the street for properties in conservation zones, which occasionally forces panels onto a less productive roof plane. Check with your council before finalising a design if your property is affected. It is far easier to resolve before installation than afterwards. Ask the installer for the figure in writing.

Regional NSW Costs

Regional installations often price slightly above Sydney despite lower overheads, because travel and a thinner installer market work against the usual pattern. Some regional areas also enjoy better solar resource than the coast, producing more per kilowatt installed and improving the return. Ask how travel is charged and whether the installer services your area regularly. An installer based three hours away carries costs that show up somewhere in the price.

Network constraints are frequently tighter in regional areas. Rural networks were not built for widespread export and distributors sometimes apply lower limits or additional conditions, which affects larger systems disproportionately. Establish this first, before anything else in the process. A 10kW system on a heavily constrained rural connection may not be the right choice. That number decides more than the panel brand does.

After sales support deserves weight in a regional decision. An installer who cannot easily return for a warranty call leaves you with a system and no practical service path, and the cheapest quote from a distant operator can prove expensive when something fails. Ask directly how warranty callouts are handled in your area. A local installer at a modest premium is often the better purchase.

Properties with weak or unreliable grid supply have different priorities entirely. Where outages are common, storage and backup capability matter more than optimising export revenue, and the system design should reflect that. Standalone arrangements are covered at off-grid solar system costs. Design for the problem you actually have. Worth confirming before you compare quotes.

Choosing an Installer

Clean Energy Council accreditation is the baseline, not a distinguishing feature, and it is worth checking the register directly. Accreditation is required both to claim the federal rebate and to produce a compliant installation, so an unaccredited installer costs you the rebate as well as the compliance. The number is public and takes a minute to check. Any installer reluctant to provide it has answered the question.

Ask who will physically be on your roof. A number of companies sell under one brand and subcontract installation to crews trading under another, which is not automatically a problem but does change who carries the workmanship warranty and who returns for a service call. The answer should come back directly, without deflection. Where subcontracting is involved, get the warranty obligations documented in the contract. Get the distributor position established first.

Longevity matters more in solar than in most trades because the warranties run for decades. A panel performance warranty lasting 25 years is only as useful as the entity honouring it, and the installer's own workmanship warranty depends entirely on that business still trading when you need it. Established local operators with a service history are worth a premium over a company with no local track record. Ask how long they have been installing in your area specifically.

High pressure sales tactics remain common in this industry and are a reliable warning sign. Deals expiring at midnight, prices available only if you sign today and reluctance to leave a written quote for consideration all point to a business model built on pressure. A quote you cannot take away and compare is not a quote. Consumer guarantees that apply regardless of what is said verbally are explained at accc.gov.au. A site visit beats a phone estimate every time.

Ask what the installer would specify for your roof and why. An operator who asks about your consumption pattern, your future plans and your roof condition before naming a system size is designing for the household instead of selling a package. That order of conversation is a useful signal about the rest of the engagement. Listen for the questions before the recommendation arrives.

Get the full document set before final payment. The compliance certificate, the network approval, all four warranty documents and the monitoring credentials should be in your hands at handover. Chasing paperwork from an installer who has already been paid is considerably harder than requesting it beforehand. Treat the handover pack as part of what you are buying. Check the accreditation number rather than the logo.

Tariffs and Retailer Plans

Your electricity plan affects the return on a 10kW system almost as much as the system itself does. Feed-in tariffs vary between retailers and have generally declined as rooftop solar has become widespread, while the retail rate you pay for imported power has moved in the opposite direction. That widening gap is precisely why self consumption matters more each year. Review your plan once the system is running, since the one that suited you before solar rarely suits you after.

A high feed-in tariff is not automatically the better plan. Retailers offering headline feed-in rates frequently charge higher daily supply charges or higher usage rates to fund them, and for a household consuming most of its generation the higher import rate costs more than the better export rate returns. Model the whole bill, because a single number tells you nothing on its own. The right plan depends on your export ratio. Shifting usage into daylight hours costs nothing.

Time of use tariffs interact with solar in ways that can help or hurt. Where peak periods fall in the late afternoon and evening, a solar system without storage is generating little during exactly the expensive window, which can leave a household worse off than on a flat rate. Where peak periods extend across the middle of the day, the opposite applies. Check when your peak windows actually fall before switching.

Demand tariffs are increasingly common and are worth understanding before you accept one. These charge based on your highest usage in a short interval during a defined period, which means a single burst of consumption can set a charge for the whole billing cycle regardless of total usage. Solar does not necessarily protect you from a demand charge set on a winter evening. Read the tariff structure itself, since the marketing summary rarely mentions how the charge is calculated. Ask what the export limit is on your street.

Retailers change their solar offerings regularly and existing customers are rarely moved onto better terms automatically. A plan that was competitive when the system was installed may be well behind the market two years later, and switching is generally straightforward. Set a reminder to compare annually. This costs nothing and frequently recovers more than a cleaning service would.

Feed-in arrangements also differ in how they treat larger systems. Some retailers cap the volume eligible for the headline rate or apply a lower rate above a threshold, which affects a 10kW system far more than a small one. Read the fine print on export volume, since the advertised rate may not apply to everything you send. Current tariff detail is covered at solar feed-in tariff guidance. The gross figure and the net figure are different numbers.

What to Look Out For

Confirm the export limit before comparing prices. Network distributors cap how much a property can send to the grid based on area and supply type, and single phase properties are commonly limited well below system capacity, which means a 10kW array may have a substantial portion of its surplus curtailed rather than sold. Get the approved capacity and export limit in writing from the installer before signing anything. Where a three phase upgrade at $2,000 to $4,500 would lift that limit, have the installer model the return both ways rather than assuming the upgrade pays for itself.

Verify Clean Energy Council accreditation independently. Accreditation is required both for the federal rebate and for a compliant installation, and a logo on a brochure is not verification, so check the installer's accreditation number against the register directly. Ask who will physically be on your roof, since some companies sell under one name and subcontract the installation to another. Licensing and complaint history can be checked through fairtrading.nsw.gov.au. Confirm what happens if approval comes back capped.

Be careful comparing quotes that are not on the same basis. Some are net of the federal rebate and some are gross, some include a switchboard upgrade and some exclude it as a likely variation, and some specify mounting hardware while others say nothing about it. Ask every installer for the same scope with exclusions stated explicitly. A quote that is dramatically cheaper is usually cheaper for a reason that is written down somewhere or not written down at all.

Treat payback claims with scepticism. Three to five year payback is achievable for a household with a pool, ducted cooling or an electric vehicle charging during daylight, and considerably longer for a household that is empty on weekdays and exports most of its generation at a low feed-in rate. Ask the installer to model payback against your actual bills and consumption pattern. The difference between those two calculations is often several years. Ask which components carry a coastal rating.

Get the four warranties in writing and understand which is which. Panel product warranty, panel performance warranty, inverter warranty and the installer's own workmanship warranty are separate instruments with different terms and different durations. The workmanship warranty is the one that matters most in practice and the one most dependent on the installer still trading in five years. Financing arrangements that affect who holds those obligations are covered at solar financing options.