Good evening everybody.
I'm not going to get into a whole lot of detail here because there are far too many variables that will have to be taken into consideration (like line loss, etc), but I am going to give you a link that will help you find what your electrical demands are. It will probably take you a while if you're going to list each and every device you are going to be using, but if you are going to do this right, you have to, otherwise you risk underpowering your items, damaging them and your power source.
You can't just hook a generator or solar bank/invertor to your breaker box and expect everything to be all hunky-dory, although many people do make that mistake.
There are 3 ways to determine how much power a device uses. Since most electrical outlets are ~110v AC that makes it more simple (although your big items like stove and furnace are 220), but other times, a device has a small AC or DC adapter that changes it to a different voltage that you will have to look at.
Nevertheless, the voltage will be listed either on the plug or on the device itself, and usually the amperage (amps) will be listed somewhere on the device or the actual plug adapter.
To make a long story short, you will need to know at least 2 power ratings of the device to get the wattage (which is what most invertors and generators are rated at).
In the link, you input the voltage and the amperage and that will tell you how many watts the device uses.
http://www.supercircuits.com/resources/ ... -Converter
Just for example, I wanted to determine the power rating of my refrigerator.
It is 120 volts input, and pulls 6.5 amps peak, and that equals to using a max of 780 watts of the invertor.
Another example of a power hungry device is my computer setup. Believe it or not, but my particular setup is about 500 watts by the time you add the tower, monitor, modem, and router.
So that just goes to show it doesn't take long before a low powered invertor/generator to meet their max power output. Besides running on their own battery for extended times, laptops rule for long term backup devices over a conventional desktop.
I mostly wanted to provide the link above to help everyone determine just how large of an invertor (or generator) you need for the devices that you can't live without because they are generally rated for how many watts they'll generate and batteries are rated in amp (hours) to know how long they will maintain that power.
And the link above is the easiest/fastest way to determine how big of a generator/invertor you're going to need.
-------------------------------
I am editing this to add how to calculate aH (or amp hours) for how to calculate how long a battery will run a given device. Mostly to help you determine how large (or small) your battery bank should be.
Multiply the number of watts by the number of hours to calculate watt-hours.
If you know your computer uses 30 watts of power and you want a battery to power it for 4 hours, you need 120 watt-hours of stored energy. 30(watts) x 4(hours)=120 watt hours
Divide this figure by the voltage to calculate amp-hours.
For this example, the battery is rated at 12 volts, divide 120 watt-hours by 12 volts. This tells you the computer needs at least 10 amp-hours to run your laptop for four hours.
I hope these math formula's can be of some help to anyone trying to design their solar system/battery size/off grid power needs.
I'm not going to get into a whole lot of detail here because there are far too many variables that will have to be taken into consideration (like line loss, etc), but I am going to give you a link that will help you find what your electrical demands are. It will probably take you a while if you're going to list each and every device you are going to be using, but if you are going to do this right, you have to, otherwise you risk underpowering your items, damaging them and your power source.
You can't just hook a generator or solar bank/invertor to your breaker box and expect everything to be all hunky-dory, although many people do make that mistake.
There are 3 ways to determine how much power a device uses. Since most electrical outlets are ~110v AC that makes it more simple (although your big items like stove and furnace are 220), but other times, a device has a small AC or DC adapter that changes it to a different voltage that you will have to look at.
Nevertheless, the voltage will be listed either on the plug or on the device itself, and usually the amperage (amps) will be listed somewhere on the device or the actual plug adapter.
To make a long story short, you will need to know at least 2 power ratings of the device to get the wattage (which is what most invertors and generators are rated at).
In the link, you input the voltage and the amperage and that will tell you how many watts the device uses.
http://www.supercircuits.com/resources/ ... -Converter
Just for example, I wanted to determine the power rating of my refrigerator.
It is 120 volts input, and pulls 6.5 amps peak, and that equals to using a max of 780 watts of the invertor.
Another example of a power hungry device is my computer setup. Believe it or not, but my particular setup is about 500 watts by the time you add the tower, monitor, modem, and router.
So that just goes to show it doesn't take long before a low powered invertor/generator to meet their max power output. Besides running on their own battery for extended times, laptops rule for long term backup devices over a conventional desktop.
I mostly wanted to provide the link above to help everyone determine just how large of an invertor (or generator) you need for the devices that you can't live without because they are generally rated for how many watts they'll generate and batteries are rated in amp (hours) to know how long they will maintain that power.
And the link above is the easiest/fastest way to determine how big of a generator/invertor you're going to need.
-------------------------------
I am editing this to add how to calculate aH (or amp hours) for how to calculate how long a battery will run a given device. Mostly to help you determine how large (or small) your battery bank should be.
Multiply the number of watts by the number of hours to calculate watt-hours.
If you know your computer uses 30 watts of power and you want a battery to power it for 4 hours, you need 120 watt-hours of stored energy. 30(watts) x 4(hours)=120 watt hours
Divide this figure by the voltage to calculate amp-hours.
For this example, the battery is rated at 12 volts, divide 120 watt-hours by 12 volts. This tells you the computer needs at least 10 amp-hours to run your laptop for four hours.
I hope these math formula's can be of some help to anyone trying to design their solar system/battery size/off grid power needs.
