Grid-Tie solar power is the most widely installed form of solar energy. The economics of grid-tie solar power packages afford the purchaser the quickest return on their investment and the most immediate visible effects on their energy bills. Because grid-tie systems are the most widely installed, and utilize the most affordable equipment, they can be set-up and commissioned in the shortest time period. These systems include solar panels, roof or ground mounts, an inverter system, and an outdoor power disconnect. Once these systems are installed they are connected to your breaker panel.
Hooking a grid-tie solar power package into your buildings electrical breaker panel means that the solar power is also connected to your power companies power grid. Because of this, when you experience a power outage the inverter system detects this and automatically shuts the power off from the solar panels. This means that your building will not receive solar power in the event of a power outage and cannot be used. UL-1741 is the specification that power companies have adopted for grid-tie power inverters for the safety of electrical workers. When the power goes out, electrical workers may need to service the lines that connect to your solar power system. If your solar power system were to send electricity through the lines they are servicing then it can put these workers’ lives at risk. Power companies also require owners of a solar power system to install an outdoor disconnect between the solar power system and your building. The power company will also require you to go through an application process to make sure your system is safe to connect to their electrical grid and inform them of where the outdoor electrical disconnect is located. Electrical line workers need to know how to safely disconnect your solar panels if they need to service the electrical lines in your area.
Advantages of a grid-tie system include: affordability, ease of installation, less maintenance, and a quicker return period. The return period is based on your electric rate and the size of your solar power package. It will also depend if you can utilize the entire 30% tax credit available on your federal tax return. You can use our Solar Power Generation Calculator – for Grid-Tie to determine how much your system will most likely generate in a month. If you use the kWh (killowatt hour) number it generates then you can multiply that number by your electric rate. The $ amount this calculation generates tells you how much you can save per month. Multiply that by the 12 months in a year and you have your annual $ savings. The formula is illustrated below:
(Electric Rate x Solar kWh production) x 12 = annual savings
ROI Years (return on investment) = [$Solar Power Package – ($Solar Power Package x 0.3)] / annual savings
We plan on releasing a calculator in the future that can help you make these calculations. In Oklahoma you can expect a payback period for a residence of about 6-8 years depending on your power rate and if you can utilize the full 30% Federal Investment Tax Credit.
