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I'm a college student, and recently got a return of some extra scholarship money from my university.
Thinking about what to spend with it, I realized that I don't actually have the time to watch much tv anymore, so that ruled out a new flat panel. So, I started researching hydroponics and decided to build a hydroponic garden. But grow lights would run the electricity bill up way too high, so I need to build it outside, on the patio. Running power cords everywhere isn't my idea of fun, so I think I need a solar powered solution.
First I would require two 5 watt aquarium air pumps. I'll also need a small water pump. Looking at other solar powered pumps on Amazon most of them use 5 watts to go about half a meter high, so I figure to go 3 feet high will be about 10 watts. But I'm not sure about that.
Anyways, that's a total of 20W. Reading through these forums I've learned I need panels that produce about twice as much as what I need, due to loses from the inverter, battery, etc. So running my system 7 hours a day (using a timer) should be 140W and I should need 280W of power to do that.
Living in Florida I should have no problem getting 5 hours of sunlight a day. A 60 watt panel would produce 300W of power in that time, more than enough. But, I'll have the panels behind a screen enclosure. I don't know if that will affect panel output.
For my battery I believe I need 3 days of backup power, incase a day is cloudy. I live in Florida, so its either blinding sunlight or rain, but usually never the same two days in a row (minus the hour long daily thunderstorms in summer, but those are only an hour long, then its back to blinding sun). 300W * 3 days is 900W. 900W / 12V battery = 75 amp hours. Are my calculations correct?
Also, for battery charging purposes, the panels I'm looking at (link at the bottom) say they produce power even in the shade / in cloudy conditions, because they are "amorphous." That should help for rainy summer days.
Now, my problem. I currently have a 3W fish tank air pump. I've plugged it into a Kill-a-Watt and it correctly shows the 3W's it's using. But when I hit the current button about 0.17 amps is shown. 120V * 0.17 is way more than 3W. If I remember my physics correctly its 20.4VA, which is some kinda weird watt with the power factor calculated (I don't really remember). Does any of this matter, or is a watt a watt no matter what the power factor VA-thingy is? 3W from the wall is 3W from an inverter?
Also, I'll be putting everything outside, in the hot Florida sun. The panels I'm looking at say they are good up to 176 degrees Fahrenheit, but I'm a little concerned about the inverter, charge controller, and battery. I'll be putting everything in a plastic storage bin to prevent water damage, but I know that box will get really hot. I'll drill some holes in the side for air flow, but I'm not sure if that will be enough. If anybody has any experience with this and could help me I would be grateful.
The solar panels I'm thinking about getting:
Thank you for all the help! Here is to hydroponically grown corn, turning into home made Tostitos! Well ... hopefully, anyways.
Thinking about what to spend with it, I realized that I don't actually have the time to watch much tv anymore, so that ruled out a new flat panel. So, I started researching hydroponics and decided to build a hydroponic garden. But grow lights would run the electricity bill up way too high, so I need to build it outside, on the patio. Running power cords everywhere isn't my idea of fun, so I think I need a solar powered solution.
First I would require two 5 watt aquarium air pumps. I'll also need a small water pump. Looking at other solar powered pumps on Amazon most of them use 5 watts to go about half a meter high, so I figure to go 3 feet high will be about 10 watts. But I'm not sure about that.
Anyways, that's a total of 20W. Reading through these forums I've learned I need panels that produce about twice as much as what I need, due to loses from the inverter, battery, etc. So running my system 7 hours a day (using a timer) should be 140W and I should need 280W of power to do that.
Living in Florida I should have no problem getting 5 hours of sunlight a day. A 60 watt panel would produce 300W of power in that time, more than enough. But, I'll have the panels behind a screen enclosure. I don't know if that will affect panel output.
For my battery I believe I need 3 days of backup power, incase a day is cloudy. I live in Florida, so its either blinding sunlight or rain, but usually never the same two days in a row (minus the hour long daily thunderstorms in summer, but those are only an hour long, then its back to blinding sun). 300W * 3 days is 900W. 900W / 12V battery = 75 amp hours. Are my calculations correct?
Also, for battery charging purposes, the panels I'm looking at (link at the bottom) say they produce power even in the shade / in cloudy conditions, because they are "amorphous." That should help for rainy summer days.
Now, my problem. I currently have a 3W fish tank air pump. I've plugged it into a Kill-a-Watt and it correctly shows the 3W's it's using. But when I hit the current button about 0.17 amps is shown. 120V * 0.17 is way more than 3W. If I remember my physics correctly its 20.4VA, which is some kinda weird watt with the power factor calculated (I don't really remember). Does any of this matter, or is a watt a watt no matter what the power factor VA-thingy is? 3W from the wall is 3W from an inverter?
Also, I'll be putting everything outside, in the hot Florida sun. The panels I'm looking at say they are good up to 176 degrees Fahrenheit, but I'm a little concerned about the inverter, charge controller, and battery. I'll be putting everything in a plastic storage bin to prevent water damage, but I know that box will get really hot. I'll drill some holes in the side for air flow, but I'm not sure if that will be enough. If anybody has any experience with this and could help me I would be grateful.
The solar panels I'm thinking about getting:
Thank you for all the help! Here is to hydroponically grown corn, turning into home made Tostitos! Well ... hopefully, anyways.