Solar Power System 3D Designer — PV, BESS & EV

Free split-screen designer for a residential solar + storage + EV system. Explore a 3D PV array, hybrid inverter, BESS, and EV charger linked to a one-line per NEC 690 and 705.

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About the Solar Power System 3D Designer

This free interactive 3D model walks you through a complete solar-plus-storage system — the PV array, inverters, combiner, battery storage (BESS), EV charging, and the grid connection. Click any component to see what it does and how energy flows from the panels to the loads, the battery, and the utility. It's a visual learning tool for solar designers, electrical engineers, installers, and students learning how PV systems are wired per NEC 690 and 705.

What the model shows

The viewer covers the full DC-to-AC path of a residential solar system:

• PV array — the solar panels that convert sunlight to DC electricity. • Inverters — string inverters or microinverters that convert DC to usable AC. • Combiner — where multiple PV strings are joined and protected before the inverter. • Battery storage (BESS) — stores excess energy for use at night or during outages. • EV charging — an electric-vehicle charger served by the system. • Net metering / grid tie — the utility connection that exports surplus and imports when needed.

How a solar PV system works

Solar panels generate DC electricity from sunlight. An inverter converts that DC into AC that powers the home and ties to the grid — either one central string inverter for the whole array, or microinverters mounted at each panel. Surplus energy can charge a battery (BESS) for use after sunset or during outages, or be exported to the utility through net metering, which credits the customer for energy sent back. When the panels can't meet demand, the system draws from the battery and then the grid. NEC Articles 690 and 705 govern the PV wiring, overcurrent protection, and how the system interconnects with the utility.

How to use the viewer

1. Drag to orbit the system, scroll to zoom, and pan to move around. 2. Click the PV array, inverter, combiner, battery, or EV charger to read what each does. 3. Follow the energy path (panels → inverter → loads → battery/grid) to see how power is generated, stored, and exported.

Frequently asked questions

How does solar PV work?

Photovoltaic (PV) panels use semiconductor cells that release electrons when struck by sunlight, producing direct current (DC). An inverter converts that DC into alternating current (AC) to power the building and synchronize with the grid. The amount of energy produced depends on panel size, sunlight, orientation, and temperature.

What is the difference between a string inverter and a microinverter?

A string inverter is a single central unit that converts the DC from a series-connected string of panels into AC. Microinverters are small inverters mounted at each panel, converting DC to AC right there. Microinverters offer per-panel optimization and better performance under shading, while string inverters are typically cheaper for unshaded arrays.

What is BESS (battery energy storage)?

BESS stands for battery energy storage system — the batteries and controls that store electrical energy for later use. In a solar system, a BESS stores surplus daytime production to power the home at night, provide backup during outages, and shift energy use to avoid expensive grid hours.

What is the difference between AC and DC coupling?

In a DC-coupled system the battery connects on the DC side and shares the inverter with the PV array, which is efficient for new installs. In an AC-coupled system the battery has its own inverter and connects on the AC side, which is flexible for adding storage to an existing solar system. Each has trade-offs in cost and round-trip efficiency.

What is net metering?

Net metering is a utility billing arrangement that credits a solar customer for surplus energy exported to the grid. When the panels produce more than the home uses, the meter effectively runs backward; when the home draws from the grid, it runs forward. The customer is billed on the net difference, making the grid act like a virtual battery.

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