Selection & System Sizing
What Information Is Required Before Quoting a Complete Off-Grid Solar System?
The minimum technical and commercial inputs needed to size PV, battery, inverter, protection and logistics without guessing.
Quick answer
A complete off-grid quotation requires the project location, destination port or city, appliance-by-appliance load list, operating hours, daytime/nighttime split, required autonomy, system mode, quantity, budget, voltage and frequency. Air conditioners, pumps and motors need model or nameplate data. Without these inputs, only a needs-confirmation proposal—not a final configuration or price—is responsible.
1. Location and supply mode
Provide country, city or coordinates and the destination port or delivery city. State whether the site is fully off-grid, grid-backed hybrid, generator-backed or intended mainly for backup. Local solar resource, ambient temperature and grid behavior affect the design.
2. Complete appliance list
For every appliance provide:
| Required field | Why it matters |
|---|---|
| Appliance and quantity | Prevents omitted or duplicated loads |
| Rated and maximum input watts | Determines daily energy and inverter power |
| Operating hours per day | Converts power into kWh/day |
| Daytime vs nighttime hours | Separates direct-solar and battery demand |
| Simultaneous operation | Establishes peak continuous power |
| Starting or surge current | Sizes inverter for motors and compressors |
For air conditioners, include quantity, BTU/h or cooling kW, exact model, rated/maximum electrical input and expected hours. For pumps, compressors, refrigerators and machinery, provide a nameplate photo and starting method.
3. Backup and autonomy requirement
State which loads are critical and how long they must run without sun or grid. “One night” should be converted into hours and a load schedule. If multiple cloudy days must be covered, specify the required autonomy and whether a generator is available.
4. Electrical requirements
Confirm:
- AC output voltage and frequency;
- single-phase or three-phase;
- required DC outputs, if any;
- installation indoor/outdoor conditions;
- maximum ambient temperature and unusual dust, humidity or salt exposure;
- required local standards or approvals.
Do not assume 220 V/50 Hz or 120 V/60 Hz from the country name alone when a project specification is available.
5. Commercial and delivery inputs
Provide order quantity, target delivery timing, destination, budget range and requested Incoterm. State whether the request is for a standard Sharxell-branded system, private label, special enclosure or other customization.
Price, freight, warranty, payment terms and delivery time are commercial outputs that require review after configuration and supplier evidence are confirmed.
What a proper quotation should show
A reviewable proposal should identify the design assumptions, daily load, PV array, nominal and usable battery energy, inverter continuous/surge rating, principal protection, major cable assumptions and excluded installation scope. Alternative configurations should explain the trade-off rather than simply change the price.
If required inputs are missing, Sharxell should issue a needs-confirmation list. A guessed “complete system” can be undersized, overpriced or unsafe.
FAQ
Can Sharxell quote from a monthly electricity bill alone?
A bill can support a grid-tied estimate, but it does not show peak power, critical loads, motor surge or day/night distribution. An off-grid design still needs a load schedule.
Why are city and destination port both required?
The city supports solar and temperature assumptions; the destination and quantity support packing, freight and commercial planning.