Solar questions

Our friend Ray sent me a few questions on my solar installation. I've decided to post them here, just so that everyone get's to read the answers, just in case they had them as well.

"If your meter is running backwards, and I'm certainly not doubting that, then it should mean that your system is supplying some of its power into the central grid, and therefore, you are in effect acting as a source of private generation for the electric company."

You are absolutely correct on this. We are supplying any that we don't use out onto the grid. I think it's great when I hear my neigobors air conditioner running and I know that I'm creating the electricity being sold to them...

"And they also ought to have installed some special devices to prevent your system from energizing theirs during those times when they may need to perform maintenance on those lines, because if a crew works on their lines and they haven't got a means of isolating you from it, then your system could theoretically re-energize a portion of their system that they might be assuming was "dead" and therefore safe to touch, and that could be tragic."

Yes, the inverters that create the AC power from the DC voltage on the panels are designed to be grid-tied. They constantly monitor the incoming utility power and if it goes down, the inverters instantly shut themselves off. When the grid power is restored, they in turn turn themselves back on. This is required for the very reason you mention.

"I assume, however, that all of that was included in the planning of it, and therefore isn't a problem - but that meter running backwards has me a little concerned, because the only way that usually happens is if the power is flowing in the opposite direction - meaning from you back to them. And if they can't see negative readings, or don't want to recognize that there really are some, then they're throwing the rule book out the window, and leaving themselves wide open to a possibly serious accident."

Electricity is flowing back onto the grid. If there's a demand locally, I'll supply it. It's the path of least resistance. As far as their not being able to read negative numbers, I need to correct that slightly. When I said that, I was referring to their accounting/billing system completely. As I said above, the inverters take care of the safety concerns. There are also manual disconnect switches that can be thrown to the off position.

Hopefully that clears it up a bit. Any other questions, please feel free to post and I'll try and get you an answer. In another post I'll explain how the system is financed.