Solar Panel Installation Guides and Best Practices

A solar installation done right at commissioning pays dividends for decades. Suboptimal panel placement, incorrect string wiring, and missed commissioning checks are the root cause of many performance gaps that monitoring later reveals - but by that point, correction requires costly retrofitting.

This category covers solar installation from site assessment through final commissioning. Topics include tilt and azimuth selection for single and multi-orientation roofs, string sizing and MPPT channel allocation for different inverter models, DC and AC wiring best practices, grounding and bonding requirements, and the commissioning checks that ensure the system is operating as designed from day one.

EC JRC PVGIS simulations for a 5 kWp system show that a fully east- or west-facing array loses 15 - 20% of annual yield compared to due south - but an east-west split array on separate MPPT channels can recover most of that loss. These installation-time decisions are far cheaper to get right than to fix later.

We reference IEC 61215, NEC Article 690, and manufacturer installation manuals where applicable. See NREL's PV system installation resources for additional field guidance and code-compliance references.

A roof assessment before installation should cover five things: remaining roof lifespan (panels last 25 years - a roof with 8 years left needs replacement first), structural load capacity for panel weight plus wind uplift, shading survey across all hours of peak irradiance, compass orientation and pitch of each available surface, and roof penetration type (tile, metal, asphalt shingle each require different mounting hardware). Catching a problem at this stage costs nothing; catching it after installation means uninstalling panels.