Solar Electricity

Generating Clean Solar Electricity for your Home in Maine

With no moving parts anywhere in the entire system, grid-tied photovoltaic (PV) systems are the most reliable renewable energy technology available. This is why PV manufacturers warranty their panels for 25 years, while the expected useful lifespan of PV panels is closer to 40 years. Producing your own clean, renewable solar electricity for decades is a great way to lock in your electricity rate and transition away from the massive CO2 emissions that come from America’s coal and gas-fired power plants. PV technology has been in use for more than 60 years, which means that today’s systems are highly evolved, reliable and efficient. Locally produced solar electricity eliminates the huge amounts of energy wasted through inefficient long-distance transmission of electricity over the utility grid.

What does Grid-Tied mean?

Battery-based solar electric systems were common until the grid-tied inverter was developed. Modern inverter technology eliminates the cost, complexity and toxicity associated with lead-acid battery storage systems. Rather than connecting solar panels to a battery bank, the panels are connected directly to the inverter, which feeds clean electricity into the building’s electrical system and/or the local utility grid. The inverter allows your solar electric system to feed surplus solar power to the grid, or seamlessly draw electricity from the grid when there is not enough sunshine to meet your demand. During the summer months, when you are likely to be producing more than you need, the surplus feeds your neighbor’s demand and you get a credit on your bill from the utility.

Under Maine’s net-metering law, your local utility is required to install a second electric meter at your home or business, free of charge, when we install your solar electric system. The new meter records electricity that you export to the grid while the existing meter records imported electricity. Each month the utility will reconcile the two meters and either bill your account or credit your account accordingly. Credits can carry forward for a maximum of 13 months. At no time will the utility ‘pay’ you for surplus electricity produced by a grid-tied solar electric system.

How it Works

Solar electric panels are typically mounted on a south-facing roof section, but we also have plenty of experience ground-mounting systems when the roof is not a viable option. Major system components include the PV panels, wire and conduit, and the inverter.

When sunshine falls on the PV panels, direct current (DC) electricity is generated and flows through a wire to the inverter. The inverter converts the DC electricity to alternating current (AC), which is the type required by your home appliances. The AC electricity flows from the inverter through a wire into your electric panel. The solar electricity will then flow through your electric panel and satisfy any household demand. If your solar electric system is producing more than the demand in your home, the surplus will then flow out through your ‘export’ electric meter and travel against the normal flow of electricity through the utility line serving your home and back out onto the grid, looking for the next closest demand.