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1. Goals and system type

This guide walks you through designing a rooftop solar system — with or without a battery — in the order a real job needs the decisions. Work through it step by step and you will finish ready for installation: a documented design to brief a qualified installer, or to continue in Photonik Pro. This is a design and planning guide, not an installation or wiring guide.

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Test yourself with the quiz. After the theory on each step, a short quiz lets you check the trade-offs with real numbers — system type, orientation, battery sizing, economics, and more. You can also work through every step quiz in order from the quiz hub.

What you will finish with

This guide prepares you for installation. It is not an installation or wiring guide — qualified electrical work and on-site procedures still apply.

Who this is for

Photonik Pro is software for solar businesses: proposals, system design, pricing, and documentation. This guide follows the same workflow.

It is not a “should I get solar?” guide. For payback, quotes, and choosing an installer, see the buying guide.

Solar-only, hybrid, or off-grid?

One choice shapes everything that follows — how your system relates to the utility grid. Pick your starting broad path on this step; later steps fill in the detail.

Three solar system types: solar-only on-grid uses panels and the grid with no battery; hybrid combines solar, battery, and grid; off-grid is independent with solar and battery only.

Which path fits your site?

Local factors still matter — what you are paid to export, what you pay to import, and how often the grid drops out. The quiz below is an early taste of how tariffs change the answer; it is not your final battery decision.

In Photonik Pro, open Project Details when you create a proposal. Set On-Grid or Off-Grid first. On-grid jobs use Energy Profile for usage and tariffs; off-grid opens the load-table path.

Project Details in Photonik with On-Grid selected, customer name, and site address fields.
Project Details — grid vs off-grid and site address.

When is a battery worth it for grid-connected systems?

On-grid sites do not need a battery decision yet — solar-only and hybrid are paths you can keep open until Step 8, once usage, tariffs, and system size are known. The quiz below helps you start to understand the trade-off between extra battery cost and greater self-sufficiency.

Step 8 — Battery storage is where this guide runs the full financial check: whether a battery pays off on your design, how many kWh to target, and how it connects to the inverter you chose in Step 6 — Choosing an inverter. If the answer is no, you can continue solar-only to Step 10 — Design and proposal review.

Local rules

Rules vary by country and region. Some places require a fully licensed electrician for any wiring; others need inspector sign-off before connection; others allow more DIY. Check what applies where you are before you build.

Goals and system type quiz

Solar-only vs adding a battery — when hybrid pays off on 25-year savings, and when a larger solar-only array beats a smaller hybrid on annual bills.

Prefer a full-screen view? Open this quiz on its own page.

Tariffs are illustrative only, in USD, not local currency.

Frequently asked questions

When do I know for sure if a battery pays off?
Step 8 — Battery storage — once you have worked through daily use (Step 3 — Energy Profile), system size (Step 4 — System size), and inverter choice (Step 6 — Choosing an inverter). The Step 1 quiz shows the idea early; Step 8 tests it on your sized design.
Can I add a battery later if I start solar-only?
Often yes, but planning upfront is cheaper and simpler. A hybrid inverter from the start avoids a costly retrofit later. Step 6 covers hybrid inverters and AC-coupled batteries; whichever inverter you choose may limit which battery brands you can add — check compatibility before you buy.
Continue to Step 2: Site assessment

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