Product guide
Start here
The Studio helps you describe the energy demand, choose an appropriate sizing method and understand how a proposed system is likely to behave under representative conditions.
On the start page, open the chevron beside Start solar sizing or Start battery backup to enter known load data directly. Use the main action when you still need to estimate the load from appliances, a bill or generator use.
Choose a workspace
These pages answer different questions. Choosing the right one is more important than entering extra detail into the wrong method.
Sizes a battery and inverter to carry selected loads through a single-day outage without recharging.
Builds an energy-first recommendation from when the load operates and the representative solar resource at the site.
Evaluates an entered or transferred system design without replacing it with the calculated recommendation.
Search for the site's city or the nearest major city. The search prioritizes direct city-name matches so a city search does not look like a complete list of its neighbourhoods. Catalogue results use approximate city reference coordinates from GeoNames (CC BY 4.0); they select a regional solar reference, not a street, neighbourhood or exact project boundary. Choose Custom location when the site needs more precise coordinates. Custom fields accept signed decimal degrees or values with N, S, E or W.
Describe the load
A useful result depends on both how much energy the site uses and when it uses it. Power and energy are related, but they are not interchangeable.
Solar System Sizing and Design Evaluation use one continuous 24-hour schedule. Each block describes the average load during that period. Leave the load at zero for any block that does not apply.
Assign start and end times so each applicable block matches the period it represents. The page keeps shared boundaries together and automatically closes the final block at the next Day load start.
Split a block when its average load changes materially within that period. A split initially keeps the same load on both sides, so edit the new value after adding the boundary. Removing an added block preserves the schedule's daily energy by transferring that energy into the adjoining block.
The schedule can contain up to five blocks in total. Starting from the default three-block schedule, this allows two additional splits. The cap keeps the profile detailed enough to capture meaningful operating changes without turning it into appliance-by-appliance scheduling.
The appliance budget should be the preferred primary method because it captures the demand the client intends to run. A utility bill or Generator + Grid use calculation can provide useful secondary estimates.
A daily total can populate Solar System Sizing, but the calculator will not invent when that energy is used. Allocate the transferred energy across the schedule and review the start and end times before calculating.
Sections are optional labels for organizing appliances by area, floor, function or another useful site grouping. Appliances may also remain in one ungrouped list.
A Section changes presentation only. It does not change appliance energy, Load Period, duty cycle, peak participation or any sizing result. Moving an appliance between Sections therefore keeps its entered values and calculation unchanged.
Removing a populated Section keeps its appliances as ungrouped rows. Use the up and down controls to reorder appliances or move them across a Section boundary without relying on drag-and-drop.
When the Appliance Budget is Backup-focused, Hours/day may remain blank. A blank value supports that appliance for the full requested backup duration; an entered value caps its default Backup runtime. Battery Backup asks for the requested duration after transfer.
Select Add solar timing and complete Hours/day before transferring a Backup-focused budget to Solar System Sizing. Individual Load Periods may still be allocated after transfer. Hiding configured timing later keeps the Solar transfer available.
Day, Off-hours and Deep Night ranges appear above the appliance list. Use Edit periods when the site follows a different schedule. Shared boundaries stay linked; extending Off-hours to the next Day start removes Deep Night after its appliances are reassigned.
Except for a 24-hour appliance, Hours/day must fit its selected period. Use Mixed and split the hours across periods when needed. A 24-hour appliance is automatically distributed across active period durations. Duty cycle reduces energy within the entered operating hours, not peak power.
Missing Load Periods trigger a schedule notice: assign them in Consumption or continue and allocate the remaining energy in Solar System Sizing. Hours that exceed a selected period pause solar transfer until corrected. Neither prevents an otherwise valid Battery Backup transfer.
Applying an Appliance Budget schedule in Solar System Sizing transfers its period boundaries and peak together. Later time changes can change energy if the block averages stay unchanged.
By default, the Appliance Budget peak includes the full rated power of every appliance, multiplied by quantity. Turn on Refine simultaneous peak in Consumption to build the highest-power combination expected to run at one time. Keep a load selected when it is expected to run throughout the requested backup duration because it overlaps every other operating load.
A shorter-runtime load may be excluded only when it will not overlap the highest-demand combination; a short runtime alone does not remove it from peak. When heavy loads are deliberately staggered, select the combination with the higher total power. Excluding an appliance from peak does not remove its energy. When only part of a multi-quantity appliance group runs at peak, split it into meaningful appliance rows. Battery Backup inherits these choices; revise them in Consumption and transfer the plan again.
Peak represents running load, not startup surge. Check the selected inverter's startup capacity for motors, pumps, compressors and other surge loads.
Battery Backup
Plan the loads that must stay on during an outage. Choose the requested backup duration, then review the energy, battery and inverter results.
Open Adjust backup appliances to exclude appliances that can remain off or change how long each needs power. When source Hours/day is blank, blank Backup runtime uses the full requested duration. When source Hours/day was entered, blank Backup runtime uses the shorter of that value and the requested duration. Mixed-period hours are added together first.
For example, a 1 kW pump normally used for 1 hour contributes 1 kWh to a 4-hour backup plan, not 4 kWh. A 24-hour appliance uses the requested duration, not 24 hours during a shorter outage.
An explicit Backup runtime may range from zero to the requested duration, in quarter-hour steps. It may exceed normal Hours/day if the outage plan requires it. Duty cycle still applies to energy; blank duty cycle means 100%.
Excluding an appliance from backup removes both its energy and its contribution to peak. An appliance excluded only from the source peak combination can still need backup energy. Peak uses full rated power, not runtime or duty-cycle averages.
Reset backup plan restores backup inclusion and runtime defaults. Appliance names, quantity, watts and source peak choices are changed in Consumption, not here. Backup adjustments do not change the source Appliance Budget.
Example: 0.8 kW for 5 hours needs 4 kWh of AC energy. With the default assumptions, the battery is 5.3 kWh, the calculated inverter minimum is 1.04 kW and the nominal suggestion is 1.5 kW.
This is a single-day, no-recharge plan. Requested backup duration and Energy represented over accept 0.25–24 hours in quarter-hour steps. Use Solar System Sizing for solar-array sizing, recharge planning or multi-day autonomy.
Direct load, daily energy and peak must be positive. Backup DoD and inverter efficiency must be greater than zero and no more than 100%. An appliance plan needs at least one included appliance and positive backup energy and peak. Results remain hidden until all required inputs are valid.
Backup calculates implied average load as required AC backup energy divided by requested backup duration. If that average exceeds the stated simultaneous peak by more than the 5% review allowance, Backup retains the stated peak and shows a neutral consistency note. The allowance suppresses small estimation or rounding differences; it does not change the energy, battery or inverter calculation. The separate inverter minimum still uses 30% operating headroom. This comparison does not account for startup surge.
A longer duration or lower Backup DoD can provide explicit contingency. Frequent deep cycling can shorten battery life. Confirm permitted DoD, continuous output and startup capacity against the selected battery and inverter datasheets; this calculation does not certify equipment compatibility.
The transferred plan is a snapshot, not a live connection. Revising Consumption does not silently change the current backup plan. Transfer again to use a revised source.
When a snapshot is already active, confirm replacement to use the entire new plan and reset backup-only adjustments. Cancel keeps the existing snapshot and adjustments. Rows are not matched by name or merged between plans.
The current snapshot and backup adjustments are retained in the session draft when navigating or refreshing the same tab. Start new design clears them along with the other workspace drafts.
Read the system
In Solar System Sizing and Design Evaluation, the array, battery and inverter solve different parts of the design. They should not be scaled together by a fixed ratio.
Rated panel capacity. Solar System Sizing checks the energy needed to serve the load directly and to replace battery energy after storage losses.
Nominal stored-energy capacity. It carries the load when PV is below demand. A larger battery stores more energy.
Continuous AC output capacity. The recommendation follows Peak simultaneous load with planning headroom. Solar charging power is checked separately.
Solar System Sizing calculates what the entered site and load require under the selected planning assumptions. Design Evaluation keeps your proposed capacities unchanged and compares them with that requirement.
A positive margin means the proposal is above the calculated requirement for that check. A negative margin shows the size of the shortfall. A margin does not confirm compatibility between specific products.
Required Solar-to-Battery Charging Power describes how quickly representative PV refill and any selected solar autonomy recovery allowance must move through the charging path within the selected Charge window. It does not increase the inverter AC output recommendation and does not independently set array kWp.
Optional planning input
Routine External Supply Support includes expected grid or generator availability when calculating the solar array and battery recommendation. The result depends on that support being available.
Enter when grid or generator support normally starts and stops, using 15-minute increments. One primary period is required and one additional period may be added. The periods cannot overlap, but they may touch. Each period can use a different source, and each generator period has its own rating. The calculator applies both periods directly to the local-time load and solar profiles. An overnight interval may stop earlier on the clock than it starts.
The source is not preselected. Choose it deliberately for each period: generator schedules are normally operator-controlled, while Grid — regular dependable supply should be used only when a dependable grid interval is a reasonable planning assumption. The standard flow does not accept average hours/day because the same duration can affect solar and battery sizing very differently depending on when it occurs.
The entered schedule is an operating assumption, not a supply forecast. If actual availability is irregular or less reliable than the entered interval, disable routine assistance and use the independent recommendation, or enter a shorter schedule that the project can reasonably depend on.
Extra low-solar autonomy remains an independent resilience target and continues to protect the complete entered load. It may therefore govern the battery or solar-recovery result even when routine external assistance reduces the normal daily recommendation.
While available, each source serves the coincident load first. In Solar Available mode, PV remains available for battery refill and external headroom supplies only the remaining planned refill requirement. In Source Only mode, PV is treated as unavailable during that support period. Each generator is limited by its own available real power. The solar array remains responsible for at least the load energy outside the modeled external-supply periods, so an unspecified charging capability cannot reduce the array to zero.
This is a planning priority, not a prediction of every inverter's internal dispatch. Real priority settings may divide solar and external energy differently between load and battery. That can change actual generator fuel use, grid energy, curtailment and measured energy flows, but it does not change the equipment sizes calculated from this stated planning basis.
Routine battery capacity follows the largest energy draw between recharge opportunities across the cyclic representative day. Daily battery refill requirement is the input energy needed to replace the energy actually discharged, including the selected storage loss. Required external charging power is the rate needed within the available external-supply period. Solar-to-battery charging power also includes the daily autonomy-recovery allowance when solar recovery is selected. A faster compatible charger may complete routine refill sooner, but it does not increase the refill energy or the battery recommendation.
Enter the generator kVA rating and rated power factor. The calculator estimates usable kW, caps assistance at that level and checks it against coincident load plus charging. Prime or standby rating, actual load power factor, temperature, altitude and transient response still need equipment review.
Use grid assistance only for a regular interval the design can reasonably depend on. The standard flow assumes the grid service can carry the connected load and does not invent a physical grid-capacity limit. The displayed load-plus-charging power is a calculated requirement; confirm that the service, inverter/charger and battery can sustain it.
Solar-led establishes the equipment and monthly service baseline. A Reduced option appears only when at least one equipment capacity can be smaller without exceeding the Solar-led PV or battery capacity, worsening any monthly energy shortfall or adding a storage-capacity failure.
A recurring energy deficit means the entered solar and routine supply do not provide enough daily energy, so a larger battery alone cannot fix it. A storage-capacity shortfall means daily energy is available, but the battery cannot carry the longest draw before recharge. Seasonal support reports only genuine monthly energy deficits after routine external contribution.
Battery planning
In Solar System Sizing and Design Evaluation, routine daily operation and an exceptional low-solar period are different planning cases. When autonomy is enabled, the calculator checks both and uses the larger battery requirement.
The battery-sizing allowance for normal representative-day cycling. A lower setting calculates a larger bank with shallower intended cycling. A higher setting may calculate a smaller bank, but allows deeper routine cycling.
This is not the inverter or BMS shutdown setting. The displayed actual routine DoD shows how deeply the selected or proposed battery cycles for the calculated daily duty.
Autonomy days represent a selected low-solar planning scenario, not a promise that the weather will follow that sequence. The calculator considers the reduced PV contribution entered for bad days and sizes the reserve for the remaining energy shortfall.
This is the lowest planned battery state of charge after the complete selected autonomy period. It appears only when extra autonomy days are enabled.
A lower minimum makes more of the nominal bank available during the event and may reduce the calculated autonomy capacity. The configured battery, BMS and inverter must permit the selected floor.
The array may increase so it can restore the depleted autonomy reserve within the selected number of normal worst-month solar days.
The routine array is retained and the external source is responsible for restoring the autonomy reserve.
Interpret performance
The charts show planning relationships based on the entered schedule and long-term solar conditions. They do not predict the output of a specific day.
Select a month to see how the load and PV profile interact through a representative 24-hour day. The chart separates energy supplied directly by PV, energy sent toward the battery and energy supplied from the battery to the load.
Solar covers load shows the periods when PV output meets or exceeds the actual scheduled load. A refined schedule can create more than one coverage period. Times are approximate and rounded to avoid implying minute-level weather precision.
The displayed local UTC offset is the clock basis for both the entered load schedule and the hourly solar profile. The calculator retains the underlying IANA time zone so applicable daylight-saving rules are included.
When only monthly solar data is available, the calculator estimates the hourly daylight shape from the site coordinates, time zone and month, then normalizes it to preserve the monthly sun-hours. This is a planning profile, not measured hourly weather.
Energy Demand includes the load plus the energy needed to replace routine battery use after storage losses. PV energy shows the representative daily production for each month.
A month is in shortfall when PV energy cannot meet that full requirement. The bar height shows the energy gap, while the colour distinguishes a shortfall month from one that meets demand.
Seasonal support expected is a planning notice for an annual-average design. It identifies seasonal months when grid or generator energy may be needed after routine battery charging. It does not mean the overall recommendation has failed, and a larger battery alone cannot replace solar energy that is not available.
You can move to Design Evaluation and increase the proposed solar array to explore covering these seasonal shortfalls. But bear in mind that the additional solar capacity will produce more PV energy than the load and battery can use during the other solar periods. This unused energy is reported as estimated curtailment.
In Design Evaluation, expected seasonal support appears in its own Seasonal energy context card and does not count against Overall design status. The notice is labelled as a hybrid operating plan for a standard design and an autonomy operating plan when extra autonomy days are selected. If the proposed array is below the calculated requirement, the notice states the array shortfall directly.
Panels and roof
Panel quantity translates the total array rating into an approximate module count. Roof capacity asks whether that quantity is likely to fit within a broad mounting-area allowance.
Pitched-roof planning reserves part of the roof for non-panel use. Flat-roof planning uses the selected Ground coverage ratio to allow for spacing and access between rows.
If the roof holds less than the required array, Solar System Sizing lets you compare the Roof-only installation with the Required capacity scenario. The latter assumes another mounting area, such as a carport or ground mount. Design Evaluation keeps the proposed array unchanged and flags the roof margin.
Refine and compare
Start with a Solar System Sizing recommendation or enter a design you already have. Adjust the design to explore different options, priorities and constraints.
The proposal meets that active representative check. It is not a blanket equipment approval.
An enabled target or active constraint needs review.
The proposal does not meet a calculated capacity target or an enabled equipment limit.
An expected operating tradeoff, such as seasonal grid or generator support, that does not represent a failed requirement.
Assumptions and limits
The Studio aims for a defensible planning representation. The results are only as reliable as the entered load and assumptions, and they should not be presented as exact operating predictions.
Optional battery charge and discharge kW ratings, C-rates and inverter battery-port limits belong only in Design Evaluation. They screen representative continuous hourly-average power. When several applicable limits are entered, the lowest becomes the bottleneck.
Passing these checks does not confirm surge performance, thermal behaviour, communications compatibility, protection coordination or manufacturer approval.
Keep the work
Session drafts retain inputs while you work. Solar System Sizing also offers named saved designs and exports for a longer-lived record.
Consumption, Battery Backup, Solar System Sizing and Design Evaluation retain their entered inputs when you move between pages or refresh the current tab. Use Clear all on Consumption to reset that calculator, or Start new design in the navigation to clear every workspace draft. Named saved designs remain available.
Consumption can populate Battery Backup or Solar System Sizing. Review an Appliance Budget schedule and choose Apply schedule to apply its periods and peak in Solar System Sizing; discard keeps the existing schedule. Battery Backup uses a snapshot with separate outage adjustments: see Battery Backup transfer guidance. Solar System Sizing can populate Design Evaluation through Tweak design.
In the Consumption Appliance Budget, download the sample and use the Appliance name, Qty, Watts and Hours/day headings. Hours/day cells may remain blank for a Backup-focused budget; complete them before Solar System Sizing. Load Periods and Duty cycle (%) are optional. The workbook is checked in your browser and is not uploaded. After you confirm, the imported appliances replace every existing Appliance Budget row.
Source period boundaries transfer with an Appliance Budget schedule into Solar System Sizing. Review period allocation and peak guidance before transferring. Battery Backup uses appliance runtime rather than the source clock schedule.
Named Solar System Sizing designs are stored in the current browser. They are not cloud records and will not automatically appear on another device or browser profile.
Solar System Sizing JSON provides a detailed customer-facing planning record with the entered load and assumptions, selected scenario, recommended capacities, key outcomes, monthly summaries, warnings and limitations. The one-page PDF keeps the result concise. Neither export includes coordinates or internal hourly calculations. Battery Backup currently has session drafts, not named saved designs or result exports.
Quick reference
These definitions describe how terms are used inside Solar Sizing Studio.