Knowledge and working practice for solar installation contractors
Solar jobs chain sales, site work, serial-tracked stock and accounting. What installer software must cover, and how to pick one you won't outgrow.
Thailand's rooftop solar tax deduction (Royal Decree 805) for installers: which systems qualify, what to collect and how to issue the e-Tax Invoice.
What a winning solar quotation must show: equipment, savings, warranties and payment terms, plus how to price without losing money and manage revisions.
Four ways to sell solar compared: who owns the system, when the installer is paid, the risks and the accounting, and how to match the model to the customer.
Control panel, inverter and battery stock so warranty claims succeed and job profits are right: serial tracking, stores by condition and FIFO lot costing.
How on-grid, off-grid and hybrid solar systems differ: power flow, behaviour in a blackout, grid approval and the customers each one suits.
LFP, NMC and lead-acid solar batteries compared on cycle life, usable capacity, safety and lifetime cost per kWh, plus what to check in the data sheet.
Size a solar battery step by step: energy used without sun, depth of discharge, efficiency and ageing, then check the solar surplus and the power rating.
A step-by-step solar payback formula with a worked 5 kWp example, the factors that speed it up or slow it down, and how to present it credibly.
