What Is a Solar Garden and How Is One Properly Engineered?

A solar garden is a small shared solar array (tens to hundreds of kW) for a defined subscriber group. Engineering covers the array's structural, electrical, and civil design at commercial scale, plus the metering that allocates production among subscribers — structured around either the state community solar tariff or a private behind-the-meter arrangement, whichever fits the scale. The design philosophy for solar gardens is commercial rigor at community scale. The array is engineered like the commercial project it is — structural verification, electrical code compliance, utility interconnection — while the program side stays as simple as the arrangement allows. Over-engineering the program kills small gardens; under-engineering the array kills them differently. The balance point is a physically robust project with the simplest subscriber structure that the tariff and the group allow.

The array engineering follows the project type: rooftop gardens get the full rooftop structural treatment — existing structure analysis, attachment design, warranty coordination — and ground-mount gardens get the geotech, grading, foundations, and racking design at their scale. The electrical design is commercial: proper one-lines, code-compliant wiring methods, inverter selection for the scale, and utility interconnection. Nothing about the shared ownership relaxes the electrical code. Interconnection deserves special attention at garden scale because the costs don't scale down proportionally. A utility study and any required upgrades cost roughly the same whether the array is 100 kW or 1 MW, which means interconnection can be a larger fraction of a garden's budget. The feasibility stage includes the utility pre-application process — hosting capacity maps, pre-application reports where the utility offers them — so the interconnection cost is known before the group commits. A garden sited on a constrained feeder is a garden with a budget problem. Metering is designed for the allocation method. Tariff-based gardens need the utility-accepted production metering and the data feeds for bill crediting; private gardens need metering accurate enough for the group's internal accounting and transparent enough that subscribers trust it. Either way, the metering is in the electrical drawings, not added later — retrofitting metering into an operating array is always more expensive.

Solar gardens live or die on total project cost versus subscriber value, and the engineering scope is sized to protect that equation. Small projects can't absorb the overhead that large ones can. The viability checklist for a solar garden.

• Interconnection cost established early via pre-application — it doesn't scale down with project size
• Site selected for buildability and grid capacity, not just subscriber convenience
• Simplest workable subscriber structure: tariff-based where the tariff fits, private where it doesn't
• Metering designed for the allocation method from the start — accuracy the subscribers can trust
• Full cost picture including agreements and subscriber management, presented before commitments