I apologize for the delay in this post, got busy this week.

My last post covered the basics of how the solar panels work at a nuclear and chemical level. This post will cover the equipment needed to interconnect the panels with your electrical system.

There are a couple of different ways to tie in your solar arrays with the utility grid. The first is referred to as Direct Grid-Tie or Intertie, this is the most simple and inexpensive way to utilize solar energy, there is no battery back-up. It starts with your solar array on your roof, these panels are connected in series and/or series-parallel depending on the need. From here it would run through a DC Disconnect and then to a Grid-Tie Inverter. The Inverter takes the DC electricity that is produced in the arrays and converts it to AC electricity. After the electricity is converted to AC, it runs through another disconnect that attaches to your main electrical panel. The electrical panel then ties to the utility company’s meter and into the utility system. If you were to produce enough power to sustain your home the utility meter would not spin at all. One major issue with this type of set-up is that if you were to lose utility power your solar arrays would no longer work, this leads us to our next Grid-tie system.

The Battery-Based system is very similar to the Intertie system except with battery back-up capabilities. With this system you would see a combiner box between the solar array and your battery bank along with a charge controller, this combiner box would be a collecting point for all of the solar array wiring. From the battery bank you would then run the DC through an inverter like in the Intertie system. From the inverter you would more than likely have a small emergency electrical panel just with critical loads (like a furnace and fridge) if you lost power. The inverter and battery bank would then power these crucial loads for your home during power loss. The inverter would also run through an AC disconnect and feed directly into your electrical panel and out through the utility meter. This type of installation is more expensive than the Intertie method, but you have some peace of mind during power outages.

Another thing to remember about battery systems is that wet-cell batteries do not last forever and typically require general maintenance 3 to 4 times a year. Unless you go with sealed batteries which do not need maintenance, but the convenience will cost ya!

There is also an off-grid solar option which relays completely on non-utility power for those that want to be “Off the Grid.”

Home Power Magazine This is a great site for some general information. If you want more in depth information you can buy a subscription. If you are serious about sustainable power I recommend getting one, I have one and have learned a lot from it.

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