What is Involved with Building a Home with a Solar-Powered Electric System

Building a home with a solar-powered electric system is a multi-step process that involves site assessment, system design, equipment selection, permitting, installation, and grid connection. The process requires the expertise of qualified professionals such as architects, engineers, and solar contractors. This guide will help you understand each step along the way and the benefits of integrating solar power into residential construction.

Choosing the Right Site for Solar Panels

To install a solar-powered electric system, you need an unobstructed view of the sky for a significant portion of the day. Panels do not function well if they are even partially in the shade. Generally, the roof is the ideal location for mounting solar panels. On pitched roofs, they can be fixed flat. For flat roofs away from the equator, they can be mounted on a tilted angle, and the direction is not critical as long as the panels can see the sun for a few hours a day.

Since the panels will be in place for many years, it is crucial to mount them on a new, metal roof with a suitable pitch. A 40-degree pitch is ideal for a location at 40 latitude. Steep roofs are beneficial because they shed snow and tree debris better. Panels are mounted on metal rails that are secured to offset brackets on the roof. For specific types of roofs, such as a dual-roof tile or a ridge-shaped metal roof, specific mounting solutions are available.

Energy Storage and System Setup

For both off-grid and grid-tied electrical systems, energy storage is essential. The choice of energy storage and the setup of the solar system depend on the size of the system. For smaller systems, multiple small charge controllers can be used in parallel, one per panel, feeding the system to several deep-cycle batteries. For larger systems, all panels can be connected in series with optimizers, and a large charge controller/inverter is used.

In a grid-tied system, you can use microinverters or a larger string inverter connected to the house breaker panel. For systems below about 10kW, microinverters are typically cheaper. Above 10kW, a large string inverter becomes more cost-effective. Microinverters can be set up with one per two panels, and seven inverters in parallel per circuit. This setup requires specific wiring configurations and meets local code requirements for a safe installation.

Optimal System Design and Installation

The system needs to be grounded, and the microinverters typically do not come with pre-wired ground connections. An appropriately sized ground wire must be run to the roof per the local codes. The system also requires a thorough assessment using a PVWatts Calculator to estimate daily energy output. Even north-facing panels can generate useful power, depending on the location and the calculation of daily energy output.

Conclusion

Building a home with a solar-powered electric system can significantly reduce utility bills and minimize your environmental impact. By carefully planning and working with qualified professionals, you can ensure that your solar system meets all safety regulations and performs optimally. Whether you are building a new home or considering upgrading an existing structure, a well-planned solar installation can be a wise investment.