For example, if you used 9,000 watts of energy in a month, dividing it by 30 would show you that you used approximately 300 watts per day.
For example, if you use 300 watts of energy a day, 300 multiplied by 24 hours gives you 7,200 watt-hours (Wh). That’s how much electricity you need your small solar power generator to be able to provide on an average day. For this example, 7,200 Wh can also be looked at as 7. 2 kilowatt-hours (kWh). It’s the same thing.
For example, if you’re going to use 330 W panels and you need 7,200 Wh of power a day, divide 7,200 by 1,500 to get 4. 8 solar panels. This means that you could generate more than enough power by using 5 330-watt solar panels. You can get a 330-W solar panel for about $250-$350 USD. They are available to order online from various solar supply companies. The panels should come with cables and hardware.
For example, if you determined you need 7. 2 kWh of power a day, you should get a battery system with a capacity of 14. 4 kWh. A 12-V battery supplies 1,200 Wh of power. If you need 14,400 watt-hours of capacity, use a battery system with 6 12-V batteries. It’s recommended to use 12-V batteries for a solar power generator, but you could also use bigger or smaller batteries if you want. For example, you could wire 2 6-V batteries together in sequence to make the equivalent of 1 12-V battery or use a single 24-V battery instead of 2 12-V batteries. You can use any deep cycle lead-acid battery for your solar battery. For example, there are batteries specifically made for solar systems. You can’t use a car battery because they are not deep cycle, which means they are not meant to be used until empty and recharged constantly, so they will wear out quickly. You can order 12-V solar batteries online for anywhere from $50-$200 USD. You may have to buy battery cables separately, which cost around $10 USD.
For example, if you’re going to use 6 12-V batteries, you would need a charge controller rated for 72 volts. The voltage rating is listed on the packaging or in the product description online of solar charge controllers. You can buy a solar charge controller rated for up to 72 V online for about $50 USD. You don’t need any cables or anything for it because the items you plug into it will have their own cables.
You can add up the watt-hour ratings of all the electrical appliances you think you might use at once, such as lights, a fridge, and a microwave, for example, to estimate how big your inverter needs to be.
The Wh rating of an inverter will be listed on the packaging or in the product description online. Keep in mind that using 7,200 Wh of power per day doesn’t necessarily mean you need an inverter that can convert all that power at once. You just need an inverter that can convert the most power you would use at any one time. You can find a 1000- to 2000-W solar inverter online for under $200 USD. It should come with the cables you need to connect it. The basic calculation for power is volts(V) x amps(A) = watts(W) = power(VA). If you are only going to separate a few circuits dedicated to emergency needs, they will have to be in a dedicated emergency subpanel. The size of the subpanel depends on the number of circuits and power requirements.
Full sunlight for solar panels is considered to be about 5 hours of direct sunlight a day. Solar power generator solar panels are smaller and more portable than on-grid solar system panels, so you can move them around later on fairly easily if you need to.
The batteries should be located nearby to the charge controller. For example, you could mount the charge controller to a basement wall and have the batteries on the floor right below it. Your solar charge controller will have clearly labeled outlets for all the cables and may have them numbered in the order you should connect things.
Your charge controller can be attached to a wall or other surface anywhere inside your home, such as in the basement, inside a closet, or under a bench.
You can also connect 12-V loads directly to the controller, in addition to using an inverter. For example, you could wire a 12-V light bulb directly to the controller to run your lights and keep your inverter completely free to plug other things into. Your controller will have 2 slots for positive and negative DC load wires that you can just plug positive and negative wires connected to something like a light bulb directly into.
