Why VoltPlan Diagrams Start with Series Solar Wiring

When you're designing a solar system, the temptation is to wire panels in parallel because it feels safer - if one panel fails, the others keep working, right? That logic makes sense for batteries, but solar panels work differently.

The key insight: Series wiring gives you 4x less power loss with smaller, cheaper wires. At 400W, you'll need 4 AWG wire for parallel but only 12 AWG for series - that's hundreds of dollars saved in copper alone. Plus, series is actually safer with lower current reducing fire risk.

Series Wiring: The Professional Standard

Here's what actually happens in the real world:

Series wiring creates higher voltage, lower current systems. That means smaller wire gauges, fewer connection points, and dramatically reduced power losses over distance. A 400W panel array wired in series at 48V pulls just 8.3 amps versus 33 amps in parallel at 12V.

Solar panels wired in serial in VoltPlan.app

The math is brutal for parallel: Those high-current parallel systems require massive wire gauges and lose significant power to resistance. We're talking about 4 AWG (25 mm²) wire versus 12 AWG (4 mm²) for the same power - that's a huge difference in copper costs alone.

More importantly, series systems are inherently safer. Lower current means less fire risk, and MPPT charge controllers are designed to handle the higher voltages efficiently. Every professional solar installer defaults to series for good reason.

Why We Focus on What Works

Could we add parallel wiring diagrams? Sure. But here's the thing: we'd rather do one thing extremely well than ten things poorly.

Series wiring covers the vast majority of real-world installations - from small RV systems to large off-grid homes. By focusing on the configuration that actually works best, we can provide better wire sizing calculations, more accurate voltage drop analysis, and clearer diagrams that won't steer you wrong.

Parallel Support: Coming When It Makes Sense

We're not anti-parallel forever. There are specific scenarios where parallel wiring makes sense - usually involving shading issues or mixing different panel types. When we add parallel support, it'll include proper current calculations, bypass diode considerations, and safety warnings about the increased fire risk.

But right now? Series wiring will solve your solar design challenges better, cheaper, and safer than parallel. That's why we start there.

Need parallel wiring for a specific application? Contact us - we're always listening to real-world requirements from actual builders.