Here is an overview of my Grid-Support Solar setup. It blends the benefits of an off-grid and an on-grid setup. I designed and installed this system myself on my house in Tegucigalpa, Honduras.
Click on the diagram to pan or zoom. Click the camera icons for photos of that part of the system.
|How it works||Your panels connect to your inverter and batteries. You have no connection to a grid. You do not need an electricity meter.||You select part (or all) of your house to be fed by a solar system. Generally, you include a transfer switch so that if the inverter cannot supply power, you will fall back to the grid power. You do not need a special meter as you will not feed power back to the grid.||With a special meter, you can sell your excess power back to the grid. It is possible to completely offset your consumption by selling this power. Special permits and equipment will always be needed.|
|When do you have power?||As long as the sun is up or your batteries are full enough to power your inverter.||As long as the sun is up, your batteries are full, or the grid has power. Almost always.||As long as the grid has power. If there is a power outage and you have no batteries, generally your system will disengage to prevent backfeeding to the grid|
|Storage||You generally need to size your batteries for how many consecutively cloudy days you experience. Could be 4 or more days.||Batteries can be quite small, or large if you want to survive power outages. You get to decide the balance.||Generally no storage. When the power goes out, you lose power too.|
|Money Savings||Every kWh of power you use is free||With smaller batteries, you will really only offset the power you use during the day. If you run appliances or AC at night, this will still be power you buy from the grid. You cannot sell power back to the grid, so you should only generate what you need.||Probably the most cost effective option. You can vastly oversize your panels because you can sell energy back to the grid.|