Grid Tie Inverters

When installing a solar photovoltaic (PV) system, you will almost undoubtedly want to use an inverter of some sort to convert the direct current to the more commonly used 120VAC, or alternating current. In your home built system, a grid tie inverter can save you significant cost and fuss by replacing the expensive batteries with the entire existing electrical grid.

Though a simple plug-in type of inverter is useful in low power situations or if only a single device needs powering, grid tie inverters are the most useful type for the most common residential applications – especially those that provide more than 100W or so.

Modern grid tie solar inverters differ also by being able to handle a great deal of power – about 8,000W being the contemporary maximum, though 2-3000 watts is far more common in residential applications. Most companies provide a selection of voltages that it will accommodate from the panels themselves. The most useful types of inverters are those capable of expanding, one panel at a time as you gradually expand your system. Since it’s the most expensive part of a grid-tie PV system, you’ll want to choose a model that leaves you room to expand, even if you don’t have the money for all the panels at once. As the price of the panels continues to drop all the time, it is likely that you’ll be able to add more as the technology continues to become more refined.

There are kits available for those who wish to build a grid tie inverter, though they are still quite expensive, still costing thousands of dollars. Indeed, most people find themselves spending quite a bit of their PV system budget on an inverter. It is not uncommon for even kits to cost between 10 and $20,000. Purchased kits should come with all the mounting hardware you’ll need, as well as detailed instructions and wiring diagrams.

It is also possible to save some money by finding a refurbished unit. The grid tie inverter you choose should be able to handle the maximum amount of current you’ll be capable of producing and have protection to prevent short circuits and other damaging releases of current. If this comes from a reputable company there should be a warranty on the unit, though it is usually shorter than the warranty on a brand new device.

When choosing a new grid-tie inverter, be sure you get one that has a lengthy parts and labour warranty. There should also be a guarantee of output efficiency for at least 20 years. Sometimes the decline in output can be quite unexpected and sharp; if your grid tie inverter does this, don’t delay in contacting the company and requesting warranty service.