YOUR POWER. PROPERLY PLANNED.A clearer path to
A clearer path to
dependable power.
Build your load list. Set your backup needs. Get an explained sizing estimate to review with your installer.
DETOPSY / PLANNING TOOL 02Every assumption.
Out in the open.
Out in the open.
Equipment-led sizing for homes, offices and small businesses.
01 / EQUIPMENT
What needs to stay on?
Preset ratings are starting estimates. Replace them with nameplate or measured input ratings.
02 / BACKUP & SOLAR
Plan for your outage.
Set the backup period, then choose the hours for each appliance. Your battery and solar plan update from those individual times.
This is the length of the outage you want to cover. Set each appliance’s own operating time below.
How long will each appliance run?
Edit the hours next to each appliance. For a 6-hour outage, you could run your lights for 6 hours, TV for 2 hours and kettle for 0.2 hours (12 minutes). Each value is independent.
For fridges and other cycling equipment, enter total time drawing the listed watts, or keep the full period if unsure. Quantities share the same hours; use separate custom entries if identical appliances have different schedules.
Choose managed startup only if equipment starts are deliberately staggered, including after power returns.
Applied to continuous power, startup demand and battery energy.
Size for one reserved backup cycle recharged in one solar day, plus any extra daytime load entered below.
Battery & conversion assumptions
Defaults assume a lithium battery. Use the battery maker’s permitted discharge depth and an efficiency appropriate to your load. Idle draw is added separately; do not include it again in the efficiency allowance.
03 / YOUR POWER PLAN
Your requirements, explained.
Planning estimate · installer verification required
This is a sizing brief, not a certified design or a promise of runtime. Match both power ratings and verify battery output, startup duration, protections and site conditions before choosing equipment.
FROM YOUR NEEDS TO A PRODUCT
Choose a power setup.
Start with the highlighted setup, or choose the alternative. We prioritise the solar input screen, then published startup watts, fewer extra batteries and smaller storage. This is a sizing shortlist, not a price or brand-quality ranking.
Prefer another brand? Get your supplier brief
How these suggestions are checked
Normal watts and total battery capacity must meet your plan. A published peak-watt rating must also meet the estimate; unknown startup ratings stay flagged. We do not substitute watts for VA and do not use X-Boost or Power Lifting ratings. Missing VA ratings, startup duration, temperature limits and actual operating losses need supplier confirmation. Extra batteries increase storage, not normal output.
The solar screen compares the planned array nameplate with the unit’s maximum PV input as a conservative first check. Passing it does not confirm panel voltage/current compatibility or recharge time. A failed screen is shown explicitly; do not connect oversized arrays without manufacturer approval.
This is a curated shortlist, not the entire market. Regional models and stock differ. No prices or availability are assumed.
See your calculated power and battery requirements
Minimum nominal storage
DC energy, reserve included
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One-day recharge estimate
TURN SOLAR CAPACITY INTO A PANEL COUNT
How many solar panels do I need?
Choose a panel wattage to see a practical quantity. Larger-wattage panels usually mean fewer panels, not less total solar capacity.
Compare other panel sizes
| Each panel | Number of panels | Total array |
|---|
These are alternative complete arrays, not panels to mix together. Panel dimensions and required roof area depend on the model you choose.
Panel count is not a wiring diagram. Your installer must check cold-weather open-circuit voltage, operating voltage, current and each solar-input port’s limits. A suitable total wattage alone does not confirm compatibility.
Equipment and calculation breakdown
| Equipment | Qty | W each | PF | Startup × | Hours | kWh |
|---|
How the estimate works
Continuous power: sum of watts × quantity. Apparent power is the sum of watts × quantity ÷ each appliance’s power factor. Both receive the design reserve and round up to the next 0.1 kW / kVA.
Startup: either all units start together, or the largest additional single-unit startup demand is added to the running load. Startup VA uses the same power factor as running VA; actual motor startup may differ. Confirm measured/nameplate starting current and the inverter’s overload duration.
Battery: equipment kWh ÷ inverter efficiency + inverter idle energy. Apply reserve for required usable DC storage, then divide by permitted discharge depth for nominal capacity. Nominal capacity rounds up to 0.1 kWh. Battery age, temperature and discharge-current limits require installer review.
Solar: (reserved usable battery energy ÷ charging efficiency + extra daytime AC energy ÷ inverter efficiency) ÷ (peak sun hours × PV yield factor). Array size rounds up to 0.1 kWp. This daily energy balance does not model weather sequences, shading geometry, charging schedules or controller limits.
Reference concepts: Victron inverter rating guide and PVWatts solar resource estimates. Detopsy uses its own simplified model, not the PVWatts calculation engine.
TAKE THE NEXT STEP
Bring a better brief to your installer.
Export the complete load schedule, assumptions and sizing requirements.
WhatsApp opens a prepared summary. Review it before sending. Your full plan stays in this browser unless you choose to share it.