This project is a simple and cheap way to integrate renewable energy into your home by turning your appliances into solar electric hybrids. Here is how it works. A solar panel (or any other renewable power source) charges a storage battery. A control circuit continuously monitors the battery's voltage. When the battery is fully charged, the circuit automatically turns on a power inverter and switches the appliance from running on grid power to running on the energy stored in the battery. Then when the battery's voltage drops too low, the circuit automatically switches the appliance back to grid power until the battery is recharged.
This design doesn't require any modification to the appliance or your home's electrical system. It can work with any power source that is capable of charging a 12V battery (examples: wind turbines, bike generators, etc.). But most importantly the system is scalable. This design is set up for outputs of up to 75 watts, but by swapping out parts for ones with higher power ratings you can power larger appliances or multiple smaller appliances at the same time. This lets you build a system that fits your energy needs and your budget.
I am still trying to make improvements to the design. So if you have any questions, problems or suggestions please leave a comment. I would really appreciate the feedback.
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Signing UpStep 1: System Overview
Here are the five basic parts of this system:
1. 12V Solar Panel (or other renewable power source)
2. 12V Rechargeable Battery
3. Control Circuit
4. 12V Power Inverter
5. Automatic Switching Circuit
When assembled, the solar panel, battery, and inverter plug into the control circuit. The automatic switching circuit plugs into the inverter and the wall outlet. Then the appliance plugs into the automatic switching circuit.
The solar panel, battery, and inverter may be purchased off-the-shelf from a variety of locations. The last two parts of the system (the control circuit and the automatic switching circuit) will need to be constructed. This is detailed in later steps.
1. 12V Solar Panel (or other renewable power source)
2. 12V Rechargeable Battery
3. Control Circuit
4. 12V Power Inverter
5. Automatic Switching Circuit
When assembled, the solar panel, battery, and inverter plug into the control circuit. The automatic switching circuit plugs into the inverter and the wall outlet. Then the appliance plugs into the automatic switching circuit.
The solar panel, battery, and inverter may be purchased off-the-shelf from a variety of locations. The last two parts of the system (the control circuit and the automatic switching circuit) will need to be constructed. This is detailed in later steps.
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If I understand it correctly, it seems like an always "on" setup, meaning that when the batteries are topped off, you'll use battery power. Once the battery reaches "low", it switches to the power on the mains from the electrical company.
The relay switches is what controls the path the electricity takes.
Couldn't the problem that "involves regularly cutting power and switching to a second power source that may be out of phase", be solved by adding a UPS backup after the automatic switching circuit and before the light bulb? (as shown in your diagram)
- U
Every time, I kept trying to test the value of pin 2 while the inverter was on, the relay would click and I could not get an accurate reading of the voltage while the system was under load. It was pretty frustrating. The only way to set the low end, was to use up the battery power until it reaches somewhere near 11V and turn the dial down until it clicked off.
But even then, I still don't know what the voltage reading is coming into pin 2.
In addition, it will be tied to the grid so if the battery is full and the solar pannel is generating electricity, it will feed into the grid, and finally, when the grid is down, use the battery (emergency).
Thanks!
I'm also having a hard time with figuring out the orientation of the relay on the breadboard, thanks so much!
http://www.mouser.com/ProductDetail/TE-Connectivity/OUDH-SS-112D000/?qs=%2fha2pyFadui2QAjXzdmwdlJkRYZqifB3R%252baei18HFruUr665Gub%252bLA%3d%3d
I sourced one a bit different but i have to move things around.
We put one on the back porch and the front porch, and bought a cute, very small Kitchen cabinet. We painted the cabinets to match the house and BOOM, we are off and running!
The cabinet was PERFECT because it had two shelves - one for the inverter, and one for the battery. We were using the existing lights - two came with each kit. We hung one set on the back porch, and one on the front porch. So, the battery started charging, and within hours, had lights on the front and back porch!
Our first set of lights blew out most likely about two months later. We went BACK through the instructions, and could find nothing. We tested the solar panel by charging another small battery. It was charging fine. We found something to plug in one of the other ports on the inverter, no issue. So, I went to the store to find bulbs to fit in there; there is nothing else to fit in there that is the correct voltage. ANYWHERE.
So, called HF - and they said, yes, we can send you new replacement bulbs at no charge AND it would take six weeks to get them. What was I going to say but ok. So, new bulbs come, we plug them in - they last two weeks and *poof* they die again. I called again; they said it would take four months this time. They had stopped using those bulbs and that inverter in the kit.
At one point shortly after this, the inverter did die. So we called for a new inverter. Got one after 3.5 months (of course, still waiting on the light bulbs). We hooked up the new inverter. Tested the other parts of it, it seemed to be fine. New bulbs finally came - they worked for less than a day. We gave up on getting more bulbs.
The front porch bulbs lasted nearly a year. Then they died. We never tried to get them replaced. In the meantime, we moved the back panel to our chicken coop, and use a small water pump for emptying out the excess water barrel, if needed, or reuse the water in the yard.
We still use the front porch panel as a trickle charge battery charger for the horse trailer and scooter batteries. But we are not using the inverter.
Is this why you are not buying the kits? Have you ever had similar problems with your inverters? Thanks!!!
Following this rules my 80W inverter works for 4 years... and counting.
On use (nightime) 4 inverters (120+120+80+80 W), sometimes at the same time, but not often.
Only mi first 7Ah battery has been replaced after 8 years duty, because not recharging above 4 VDC. (Similar to the one showed in a picture above).
My battery replacement is mandatory after 10 years duty (that one was a surprise).
An inverter allows you to use a wide range of Energy-Star appliances which are much cheaper than DC appliances, and get more use, and storage, out of your appliances.
With the cost of inverters and the power lost in the process, it seems that eliminating the inverter would be more efficient.
Just thought I would add a little useful info
cheers
Ultra Computers
If it's more than 3 x as expensive, then might as well get three cheaper ones (if space allows)..
it will be cheaper and gives the same output.. or, in other words, it's more cost-efficient...
cheers.. :)
"We have a "be nice" comment policy. Please be positive and constructive with your comments or risk being banned from our site. "
So I'll be nice and ask a constructive question, What is the cost per watt of this system, and what is the power density of the amorphous array? Then there is the matter of the 85 dollar AGM pile that Da Freight is peddling with this thing,, what is the reccomended c/20 rate versus dollar/watt ratio?
These are the real economics of DIY alternative energy.
In regards to your question, I used a 5 watt panel, 75 watt inverter and a 7 Ahr battery and was able to build the system for about $150 using parts from RadioShack. If you order the parts online you should be able build this setup for under $100. As my design lets you select the components that fit your needs, the performance is entirely dependent on the panel battery and inverter that you select.
In Kansas we've been having temperatures of 100 to 105 degrees each day this summer and our utilities bill has gone through the roof. Even if this potential rig cost $400-$500 I would still end up saving money over the course of the summer.
So, then made ââin the design, does not allow a current output over 2A, at the output of the regulator (It's the 1 design, before the all relay switch, that commute the DC and the AC).
Could anyone help me get around this?
Thank you and best regards to all!
So, then made ââin the design, does not allow a current output over 2A, at the output of the regulator (It's the 1 design, before the all relay switch, that commute the DC and the AC).
Could anyone help me get around this?
Thank you and best regards to all!
My only minor quibble is about the power inverter. All the cheap inverters are "modified sine" which is a +180V/0V/-180V/0V wave that delivers the same amount of electrical power. It works fine for CFL's and most switching power supplies that just make the line voltage DC then work from there, or for resistive loads like incandescent bulbs and heaters (or, even direct line-powered LED light strings). But for transformers (e.g. plug-in brick transformers, and many many appliances) and AC induction motors (e.g. fans, pumps), the modified sine is completely inadequate and leads to lots of waste heat and potential damage to the appliance.
I have been recommending that people instead spend the extra money and get a "pure sine" inverter (I have a 300W Samlex brand that works very well). They are a lot more expensive per-watt, but especially for a small starter system, you really can't realistically use more than 75 watts or so for any appreciable time (that 7AH battery would be dead in in an hour at 75 watts, and realistically should only be run for about 30 minutes or so; a 500W coffee maker would kill it before one pot is done). The pure sine inverter will work fine with all appliances including things that people are likely to use like chargers for phones, iPods, or batteries, laptop power supplies, monitors, TV's, and audio amplifiers.