How Solar Works
A basic solar system is comprised of:
- Solar Modules (Solar Panels): When sunlight hits the panels an electrical charge is produced within the very thin silicon wafers and flow of electricity occurs. Solar panels make direct current (DC) electricity.
- Inverter(s): The inverter converts the panels’ DC electricity to grid-compatible alternating current (AC) electricity for use in the building. Two main types of inverters for homes include string inverter or micro inverter. String inverters can be paired with optimizers and the combination works similarly to micro inverters. A commercial building with three-phase power requires a three-phase inverter.
- Balance of System (BOS): BOS components include roof racking and roof attachments, conduit and wiring, power safety disconnect (manual shutdown), meter, and monitoring unit for online monitoring.
Flow of Electricity
In the Grid-Tied Solar System diagram above, the solar array produces DC electricity that is converted to AC by and then flows through a production meter on its way into the house. The production meter measures all of the solar electricity in kWh. (Production meter readings are used to determine the Production incentive if there is such an incentive.) The solar electricity then flows into the building breaker panel where it merges with utility-supplied electricity to run lights, heat, appliances or any other uses.
As daytime turns to night, solar generates less and the grid takes over seamlessly. During bright sunny days, oftentimes solar generates more electricity than the building needs and the excess power automatically flows to the utility. When you go solar, you get a new utility meter that measures electricity in two directions, power from the utility as well as the power sent to the utility. You pay for the difference which is called net metering.
Battery Backup: Without batteries, a basic solar system automatically shuts down during a power outage; it is not a source of backup power when the grid goes down. When battery backup is added to a basic system, then battery power is used during a power outage. The backup battery is a reliable, quiet, clean-energy alternative to a noisy, gas-fired, air-polluting generator. When a Tesla Powerwall battery system is added to your solar array, not only do you have reliable back-up power but your solar array will continue to generate electricity during a power outage, and both the batteries and the solar system are eligible for the income tax credit.
System Design: Designing the best solar system to match your power needs and your roof configuration is our job. NWES goal is to generate as much power as you need, install an aesthetically good-looking and technologically efficient array, stay within the parameters of any incentive programs as well as your budget, and be fully compliant with electrical and fire safety codes. We will recommend options to you using equipment we know and trust.
Residential Size Solar System
The typical home size solar system consists of 10 to 40 solar panels installed on the house or garage roof, or on a ground mount. Depending on the amount of direct sunshine, the system will generate 50% to 100% of the electricity the home needs.
Commercial Size Solar System
Commercial size systems range from small to medium size businesses such as the Eye Care Center above to large warehouse roofs with rows and rows of solar modules below.