Grid Tie Inverter Question

Re: Grid Tie Inverter Question

A pure Grid Tie Inverter system is the least expensive to install, least expensive to maintain, and the most cost effective method to produce solar electric power.

However, you are correct, its main drawback is that it only works when your Electric Utility lines are working.

You can certainly install full off-grid systems (battery/inverter/solar panels/charge controller/generator) for remote sites. And there are hybrid systems that do grid tie for normal operation, but fail over to off-grid operation (sort of like a giant UPS).

Both of these options require batteries--which is where the additional costs really come in (expensive to buy, have to keep clean and watered--if flooded cell, and replace very 5-15 years or so)...

You can make very nice "hybrid" grid tie + off-grid systems... But it is not cheap.

Xantrex (also sold by our host) makes a very nice "XW" system if you want a large system (4-6 kW of inverter support).

Depending on where you live--a Grid Tie system can get your power down to $0.25 per kWhour, or less--without state or federal rebates.

An off-grid system is probably going to cost you $1.00 per kWhr or more (usually no rebates available)...

I don't know what a hybrid system will cost (per kWhr)--but probably somewhat closer to the $1.00 per kWhr.

Where do you want to take this discussion?

-Bill

Re: Grid Tie Inverter Question

Are you planning on installing the system yourself? Generally, the installer makes much of their profits based on the panel/inverter markups--so they usually have a couple inverters and manufacturers they can select from.

But, this is a little bit backwards to select the inverter first. My two cents would be to suggest that you size the system first, then look at the inverters that will support the system and options you are looking for.

From what I have seen, in the ~3-5 kW range, the Xantrex GT series look pretty nice--Has the AC/DC switch and does not have any fans (fans are usually the first things to fail).

Our host stands by their product--so if you end up getting the inverter and panels through your installer--you can still reference back here to see if it is one of Wind-Sun's products and be pretty sure that the product will be reliable and have good support.

Also, make sure you look at the cost per watt ($/watt) for your system components. You don't want to overspend. Some of the smaller systems (1-2 kW inverters) are pretty expensive. The larger ones usually seem to be more cost efficient).

-Bill