Solar energy is energy from the sun. Visible light, heat and UV light (sunburns) are the most evident. Solar energy can keep you warm on cold days and when it does away at sundown, then we are reminded of the air temperature and winds.
Batteries can store energy from the sun. An energy battery can be a concrete wall, pond of water, hot water storage tank, dark colored sunlit stones on your floor etc. The most efficienty energy battery for heat is trees. They have large branches and leaves that spread out to collect the sunlight and converty this into chemical energy in the form of wood that people can use for compost (leaves), building small fires (small dead or pruned branches) and large fires (cut main trunk).
Electrical batteries are used for storing electricity. The electrical system must be properly designed, cared for and used. The flooded lead-acid battery is very common and cost-efficient for solar systems. And about 97% of a battery is recyclable. You can take old degraded batteries to a battery store and trade them in towards new or refurbished batteries.
Solar panels are widely available and are common for 12 volt systems. They have outputs of 100 Watts maximum at peak efficiency, about 21 volts open circuit and achieve highest power in full sun when kept about 18 volts. I've purchased many 100 W solar panels from Windy Nation, through ebay and also their store online at windynation.com. For some reason they sell their products cheaper on ebay than on their website.
Solar charge controllers come in many forms. For an entry level solar charge controller, you can get a simple switcher that handles 12 or 24 volt systems and 30 amps for about $50 from Windy Nation at www.windynation.com. For some reason they sell their products cheaper on Ebay than on their website.
With several solar panels, a charge controller with limited connectors and multiple circuits for inverter, lights etc, I found a need for some good electrical connectors.
I've purchased audion equipment connectors. They were heavy and not very flexible if I wanted to change wire size. I've used bus bars, but they expose large surface areas to potential electrical shorts. Then, I was talking with a neighbor about his system and saw he had some plastic electrical connectors that mounted on a rail. It was very clean and professional. So I searched around. I found some electrical connectors on Ebay from Clayton at International Connector INC. His website is intconnetor.com out of Venice, Florida.
I was very happy to find these connectors. They are mountable on a rail, inexpensive and come in a variety of sizes. Also, they are easy to mount and dismount on the rail which provides flexiblity and cost-control as my electrical system changes. I can use larger DK10N connectors, smaller DK5N connectors or smaller yet the DK2.5N connectors. I can insert the stripped end of wire into the connector and use a flat blade screw driver to clamp it down. The internal metal parts are insulated in plastic which makes things safer. I can buy them in boxes of 50 for bulk discount and share them with my neighbor and add/remove parts as needed. They are very handy and a great find. They are even less expensive than use a bus bar! Goes to show that using the right part for the job is most efficient.
For a charge controller of 30 amps, I use 6 AWG (gauge) welding wire which will handle between 30-100 amps depending on how long it is. 30 amps is sufficient to handle current going into my 30 amp charge controller. I have a common anode system with the anode connected to the grounding rod outside. The anodes/positive from the solar panels get connected to several DK10N connectors. The DK10N connectors (two connections plus middle bus per connector) are snapped onto a metal rail that is screwed to a piece of plywood which is in turn screwed to a wall stud. These DK10N connectors are electrically bussed(connected) through a central push-fit bar, part# DSS10N-10. The DSS specifies the push-fit connector. The "10" in the part number specifies the size it matches (it matched the DK5N. So with (4)DK5N connectors, I can connect 4 positive leads from 4 solar panels, connect to the battery through two pieces of 6 awg wire (easily handles the 50 Amps for 1000 Watt inverter on 24 Volt system) and have 2 open connectors left.
For smaller circuits like lighting, I connect from the DK10N connectors to smaller DK5N (200 watt local inverter) or smaller yet DK2.5N connectors (1-5 amp lighting). This is for the positive "rail" or bus. For the negative bus, I use the DK4N-TF connector which holds a 5x20 fuse. Since I'm using a common anode or common positive system, then I fuse the negative wires or negative rail.
For fuses, you can put a high current 25-100 amp fuse between two batteries. This means if you draw in excess of the rated current, then (hopefully) the fuse will blow and keep your wire from getting so hot that it causes a fire.
Wires are to be fused at a lower rating than what the wire can carry. For example, a 1 amp rated wire (say for LED lighting) should have a 1 amp fuse so that if the 1 amp capacity wire is shorted (connect directly to the positive rail) then the fuse will blow and keep the wire from starting a fire or burning someone or something.
For short runs to the battery and inverter, I use flexible welding cable to make my connections. I like the welding cable because it is flexible. I also like the 6 AWG size wire because it is flexible, can carry 30 amps and more. I like the insurance of distributing large current paths over several connectors to avoid dependency on just one connector. This way if one connection is loose, gets corroded, or goes bad for any reason etc then the other connections can carry the current without creating one pointsource of heat for igniting a fire.
Many solar deep-cycle batteries of 210 AH capacity or more have large lead terminals that will accomodate 5/16" bolts. I use a stainless 5/16" bolt about 2 to 2.5 inches long and stainless nut to fasten to the battery terminal. I find the stainless steel bolt is cheaper in the long run because it resists corrosion much better than regular galvanized.
Having tired of stripping wire and crimping on expensive (and quickly corroded) tin-plated copper lugs, I have gone to using an "Mechanical Terminal Lug" made of thick pure copper that fastens to the battery through the 5/16 inch diameter stainless bolt (or #10 bolt) and on the other end to one or more wires through a clamping bolt. I make sure that the holes are at least 5/16" for connecting to the batteries. And since I'm using multiple 6 AWG wires, then I can use a size of #4-3/0 connector. I've found the ones at Home Depot in the electrical department "Burndy" #4-3/0 Offset Terminal Lugs" to be the least expensive at 2 for ~$6<./p>
For multiple wires (like 6 AWG that I use), I strip off 1 inch of insulation and clamp all the wires into the copper lug with the included lug bolt.
For corrosion resistance for connections near the batteries, you can use electrical grease to protect the wire from corrosion from the sulphuric acid coming from flooded lead-acid batteries. The bulky copper lug can then be wrapped with red (positive indication) or black (negative) electrical tape. Obviously the tape doesn't determing the polarity, but is an indication of the polarity of the wire.
The information on this website is for informational purposes only. Use at your own risk. I am not responsible.