What is a Grid Tie Inverter?
If you’re generating excess electricity with your solar panels or wind turbines, a grid tie inverter will let you sell this power to the power company.
The 1978 Federal Public Utilities Regulatory Policies Act (PURPA) states that everyone in the US has the right to sell renewable energy to their local power company. This law came about after the 1973 Arab oil embargo and is just as welcome today.
The function of an ordinary power inverter is to convert DC electricity to AC, which can then be used in the home. Inverters also convert the 12 or 24 volt electricity your installation is generating to 120 volts. Many users of renewable energy systems are missing out on the benefits of another, particular type of inverter, though. The AC power that comes from an inverter, at 120 volts and 60 cycles per second, is basically the same as power that comes right from the grid. The problem, in terms of compatibility, is that it’s unlikely that both sources are in phase with each other. If your inverter’s electricity is cycling up when the grid’s is cycling down, transferring your electricity there won’t work. The answer to this problem is a grid tie inverter. This type of inverter makes sure that your inverter is in sync with the grid.
A grid tie inverter is helpful in other ways as well. In a way, electricity always goes downhill: it flows from higher voltage to lower voltage. This is what makes it possible to charge a battery. The electricity flows from the charger, which outputs at high voltage, to the battery, at lower voltage. This is why a 12 volt battery needs a charger of over 12 volts.
This means that, if you want to send your electricity back to the grid, you’ll need it to be at a higher voltage than the electricity on the grid. A grid tie inverter will also keep track of the voltage levels to make sure that this happens. Your excess higher voltage electricity will go out to the grid, and your power meter will run in reverse.
Grid tie inverters are more expensive than regular inverters because of their expanded functionality. However, a grid tie inverter will give you the chance to actually make money using your renewable energy system, so it will justify the investment. Anyone using renewable energy should strongly consider investing in a grid tie inverter.
The idea of off grid living appeals to many people. If you are interested, take a look at Off Grid Living.
To learn more about how the solar power system works, you can check out Solar How To.
If you are looking for the best DIY charger plans, go to DIY Solar Charger.