Frequently Asked Questions

We manufacture N-type TOPCon (600W, 640W, 730W) and HJT (730W) bifacial solar modules at our own 2GW production facility. We also supply inverters, LiFePO4 batteries, and complete solar systems.

TOPCon offers the best price-performance ratio for most climates. HJT has a superior temperature coefficient (-0.24%/C vs -0.30%/C), making it 6-8% more productive in hot climates above 35C. Both are N-type bifacial technologies with 25+30 year warranties.

Yes. All JUSTSOLAR modules feature dual-glass bifacial construction. TOPCon modules have 80% bifaciality, HJT modules have 85%. Bifacial design captures reflected ground irradiance, boosting total energy yield by 5-25% depending on albedo and mounting height.

TUV Rheinland, IEC 61215, IEC 61730, CE, ISO 9001, MCS (UK). Market-specific certifications available: UL (US), BIS (India), INMETRO (Brazil). All certificates downloadable from our website.

Solar modules are priced in USD per watt ($/W). Prices vary based on module type, order quantity, silicon market conditions, and trade terms (FOB/CFR/CIF). Contact Frank for current pricing.

Standard: 30% deposit + 70% against Bill of Lading copy. Orders under $30,000: 100% prepayment. South America/Africa/India: balance before shipment. Deposit as low as 10% for established repeat buyers.

Yes, we accept Alibaba Trade Assurance for additional buyer protection. Bank wire transfer (T/T) in USD is our standard payment method.

Our MOQ is 1 full container (40HQ): 720 pieces for 600W/640W modules, or 612 pieces for 730W modules. For first-time buyers evaluating our quality, we can discuss smaller trial quantities.

You can mix different module wattages in the same order. However, solar modules fill the entire container — inverters, batteries, and mounting must ship in a separate container.

2-6 weeks depending on order size and stock availability. Stock items can ship within 1-2 weeks. We provide regular production updates and photos.

FOB Shanghai (default), CFR, and CIF. CIF is recommended for new importers — we handle ocean freight and All Risk cargo insurance. You receive modules at your destination port.

600W/640W modules: 720 pieces per 40HQ. 730W modules: 612 pieces per 40HQ. Modules fill the container completely — BOS items must ship separately.

Southeast Asia: 7-15 days. Middle East: 20-30 days. Europe: 25-40 days. Africa: 30-45 days. Latin America: 25-45 days. We provide container tracking numbers.

Yes. All CIF shipments include All Risk marine cargo insurance. Our damage rate is under 1.2% (industry average: 3-5%). If damage occurs, we handle the insurance claim on your behalf.

Yes. 100% EL (electroluminescence) testing on every pallet before shipment. EL testing detects micro-cracks, cold joints, and cell defects invisible to the naked eye.

Yes. Flash test reports with IV curves are included with every container shipment. Reports show actual measured power output under Standard Test Conditions (STC).

Absolutely. We welcome inspection by SGS, TUV SUD, Bureau Veritas, Intertek, or any agency of your choice. Pre-shipment inspection can be arranged at our factory at your discretion.

We are a manufacturer. JUST SOLAR GROUP operates its own 2GW production facility with fully automated lines. We welcome factory tours — video call or in-person. Our TUV-audited factory photos are on our About page.

25-year product warranty + 30-year linear performance warranty. First-year degradation under 1%. Annual degradation under 0.4%/year. Guaranteed output above 87.4% at year 25 and 84.8% at year 30.

Contact Frank via WhatsApp or email with photos of the issue and your order/serial numbers. Our engineering team assesses within 48 hours. Confirmed claims: replacement modules shipped at our cost.

Frank Yang (Director) handles all key accounts personally. Same WhatsApp contact from first inquiry to warranty claim. Direct access, no call center. We never ghost our customers.