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Start Big - Residential PV Stand Alone Systems
Actually, I do want a divorce
Now let’s look at our other option. We loathe the power company so deeply, we want a divorce. Or perhaps, there is no power company handily by to soak up our loathing so we’re on our own anyway. In this instance, all the above about making every watt count still applies. What changes is that one extra item is added to the system, and that is battery back-up (needed for when the sun is not
shining… like at night.) In the Queen’s opinion, this is still the weak point in a PV stand-alone system. Batteries are improving every day, but are still like little prima donnas. Always needing encouragement and attention and pampering. If you like fiddling with technical stuff (many people do), then these batteries are for you! Needless to say, the batteries add considerable expense to any system (about $2 per watt.) However, the Queen knows folks who happily get along with a stand alone PV system AND live at peace with their batteries. In some cases because they do the work themselves, or more easily, sign a maintenance contract with their solar professional.
We’re getting towards the end of this section, so time to bring up a point which merits attention. So far we’ve looked at a grid tied system, and a stand alone system. In a grid tied system, we are essentially using the grid as our battery. We make our own energy during the day, but pull from the grid at night, when sunlight is in scarce supply. There is one rather large disadvantage to this system: if the grid goes down, generally speaking, so does your system! Let’s say a hurricane passes through and the power goes out. The next day the sun comes out and your PV system is chugging away. Alas, you might not get anything from it. Why does the power company insist on this? The short answer is, they don’t want their linemen getting electrocuted from a house pouring electricity back into the grid. Fortunately, there is a way around this difficulty. Let’s say you have a generator. There are two ways it can be used. You can run a cord directly from the generator through a window and into the house where it powers a specific appliance. Or you can have your house set up with a separate
panel for emergency use. In this case, when the power goes out, you fire up your generator, plug it into the side of the house and then flip a large switch which cuts the house off from the grid and onto the emergency panel. This concept of a separate panel could also be used with a PV system. With it, linemen are safe, and while there is sunlight, you can power part of your house. The Queen’s house has a rather complex electrical system, so she can vouch for the fact that not all electricians are created equal. Some revel in complex mind boggling jobs, and some run the other way. Needless to say, a system such as this requires some extra work and expense. If your power rarely goes out, don’t bother.
There we go. We also mentioned Wind Turbines. ‘Tis a fabulous technology which - at the moment - is suitable in certain circumstances, but not all. Live out in the country, away from or at the tail end of the grid, with plenty of land, good wind and an easy to get along with local government? A hybrid system with PV for the sunny days and a wind turbine for the windy days would be perfect! There are many hybrid systems in operation, and their owners love them. See Start Medium for more information.
In the meantime, we hope this has sharpened your appetite for taking charge of your energy future. Think about it, would you rather do something now from a place of empowerment? Or … we could all wait till it becomes a matter of panic. True enough, maybe that will never happen. Even if it doesn’t wouldn’t it be nice to have the lowest power bill on the block?
If you are contemplating a PV system, click on the possibilities link and contact the Queen. She’ll help you get things going in the proper direction.
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