This project goes over the build of a Homemade medium sized and moderately priced portable solar power generator that is designed to be powered by 100W Polycrystalline Solar Panel.
The case for this portable system is from Plano sportsman, quite sturdy and rugged that a typical container. Costs about $25 . It has a nice top with handles that latch it down.
On the back of the system, we have two pin SAE port that allows the energy from the solar panel to come into the system. It directly goes into a 30A solar charge controller. The negative from the charge controller is connected to the negative of the batteries. The positive is connected via a switch to positive of the battery. The negatives and positives of the batteries are connected to each other. The negative of the inverter is connected to the negative of the battery. The positive is connected to a battery switch off circuit that is further connected to battery positive through a switch. The USB ports,12V DC outlet, DC meter all are connected to the respective terminals of the batteries.
To connect to the AC outlet from the inverter, we take a 3 wire extension cord which can be bought from the local hardware store . The negative end of this wire is connected to the negative of the shallow box AC outlet and the positive is connected via an 15A inline fuse and a current transformer. The ammeter is connected to current transformer and the 110V outlet.
On the front of the system, we have the accessory ports including a 12V power indicator , 2 USB ports with 5V one amp and 5V 2.1amp, 12V outlet, AC Voltmeter and ammeter. Amp meter tells how many amps we drawing out of the system using various appliances. This can help us understand how much solar power is being generated during the day versus solar power being utilized from the system.
The whole system is turned on a 12V master key switch that activates inverter, case temperature sensor, cooling fans , AC power outlets. We install a key and power up the AC side of the system. There is two fans on the back that push air in and draw air out of the case to keep the AC DC inverter cool.
Inside we have a deck tray made from backboard material available at Home Depot. We have installed a 400W pure sine wave inverter, a 30A MPPT solar charge controller and a 12V emergency LED light on them, also has four vents that allow air to circulate through the top portion of the case as well as through the bottom. The vents keep the batteries cool and allow any off-gas build up from the batteries to pass it through.
Here the inverter has a built in automatic shutdown feature that ensures that the batteries are not discharged to a significant level. So it is safely connected to the batteries.
Once the deck tray is taken apart, we have 2 55AH AGM sealed batteries that are wired in parallel to a 2 AWG cables to transfer the power back and forth between the batteries. These type of batteries require less maintenance. Also installed a wooden frame with exact dimension of inside of the case to keep the batteries in place and keep them from moving around.
To protect all the components we have fuses ranging from ANL 50amp fuses between the inverter and the battery , inline 30amp fuse between the solar charge controller and the batteries.
To attach jumper cables we have an option for external heavy duty battery terminals. To connect to an AC float charger we have added a SAE 2 pin port.
- How to build your own DIY off grid / grid down Solar Power Back up system from scratchThis project goes over the build of a Solar Power Grid Down Backup System to generate your own alternative power.A great way to utilize renewable energy as a backup source of power. Whatever may be the reason , may be to offset electricity bills or for self reliance to provide when the grid goes down, a solar backup system is simply a great way to provide alternative power to maintain a lifestyle of reasonable convenience. If the grid should go down, I can have a freezer, power lighting, pump water, maintain communications, use tools, and charge every little device I have from flashlights to kindles. This Off grid Solar Power System is composed of 5 components. Solar panels to generate the power, a charge controller to charge the batteries, the batteries to store the energy, the inverter to provide AC to the household items you wish to power. Also you need a Kilowatt meter. The kilowatt meter measures two things you have to know how much energy your devices draw at any given moment, and how much power they consume over time. Here we use 100 watt monocrystalline panels, a 40 amp MPPT charge controller, a 1000 watt pure sine wave inverter and to store the energy, 446 volt golf cart batteries totaling 470 amp hours. First you need to size your system by figuring out how many devices you are going to want to run at the same time. This will determine the size of your inverter, the inverters function is to take DC power from the batteries and converted to AC power for use with household appliances. If I have 1000 watt inverter, this means I can run up to 1000 watts worth of devices at the same time. Once you have evaluated every device that you feel that you are going to need, should the grid go down, you are gonna have a good idea of how much power you need to generate each day. The battery bank consists of four, six volt, Duracell SLIGC 125, golf cart batteries connected in series. Golf cart batteries are designed to deliver a lower amount of power over a longer period of time and then recharge quickly. When picking a spot to locate your panels, you have to consider that the sun will be lower towards the horizon in the winter, and closer to directly overhead in the summer. Building a system that actually tracks the sun would be best as the panels are always pointed directly at the sun. Also mount your panels as close as possible to the batteries. This is because the longer your wire run, the more energy is wasted due to resistance. You also need to select the proper gauge wire to transmit the power from the solar panels to the batteries. Between the panels and the batteries is the charge controller ,it controls the charge of the batteries and make sure that the batteries get the proper voltage that they need and that they don't get overcharged. Here we use an MPPT Solar Charge controller. If your solar panels are wired in series and connected to an MPPT charge controller, the voltage adds up ,thus giving us enough voltage to charge the batteries. An MPPT charge controller can charge your batteries nearly the entire time The sun is out. If your panels are far away and you want to save money and wiring, then the MPPT charge controller is way more efficient than PWM. The first step in making your solar system safe is making sure that there's an automatic and a manual way to disconnect power in each segment of the system. Starting right here at the battery box we have a 300 amp manual switch to kill the power from the batteries to the inverter as well as a 200 amp fuse that will blow automatically. Another component to the safety is the grounding. Grounding your system is quite easy to do. So get an eight foot grounding rod and drive it into the ground. Then pick up some copper grounding wire, some lugs and connect the frames have all the panels in any metal components in the system including the charge controller and the inverter.
- How to build a DIY Passive Solar Thermal Water Heater. Simple and Efficient!!This project goes into the build of a passive solar thermal water heater using pex pipes and 4 X 8 plywood piece. The pex pipes are sturdy and tough , doesn't easily leak. This passive solar heater can reach upto 120 - 150 F on a typical sunny day. Instead of pex pipes, you can use cheap irrigation pipe for this project. The pex pipes are more stronger and durable . The heater can be used for heating your domestic water, space or room heating or just heating a swimming pool. The box that contains the pipes are made of 4 X 4 plywood . Four pieces of 2 X 4 pressure treated lumber are joined along the sides using screws to make the frame. We staple in some bubble insulation along the dimensions of the box . Since the insulation material is silver, it will reflect heat. To avoid this ,we coat it with a flat black paint to attract the solar heat. Two holes are drilled on the sides of the frame for the inlet end of the pipe where the cold water comes in and outlet end where the hot water comes out. The inside and the outside of the heater is painted flat back using rust-oleum high heat paint to absorb maximum heat from the sun. The first layer of half inch pex tubes or irrigation pipes are secured inside the solar heater box using half inch pex talon clamps. The clamps are installed on four sides of the box securing each loop of the pipe. The second or upper layer of pipes are secured in using zip ties. The total length of the pipe is 200ft. The pipe comes in through the inlet hole and goes to the outside on the first layer , all the way around and work itself inside .It then goes through the top layer and all the way to the outside and then exit through the outlet hole. The bottom layer pipes aren't going to be exposed to the sun as much but they still will be warmed up because the whole box is covered with lexan polycarbonate sheet. The top layer with the pipe that goes outside through the outlet hole will have the highest thermal BTU. A very inexpensive reed thermometer with a 4 inch stem is installed on the side of the heater using a half inch to three eighths bushing reducer . A 4 X 8 Makrolon Polycarbonate Sheet is placed on top of the heater box and secured down in place using a No 8 One and one fourth sheet metal screws ,finishing washers and rubber grommets. Silicon adhesives are used to seal the gap formed between the sheet and the box frame. The Solar thermal heater is placed at an angle of 20 degrees. This is done with the help of leg supports with dimensions 16 and 8 inches 2 X 4 pieces at both the sides. A 50 watt Renogy Solar Panel is also installed adjacent to the heater. This Solar Panel is for powering the bilge water pump. A 500GPH 12V bilge pump is used to pump the cold water through the pipes into the heater . In order to control the flow of water through the pump , it is connected to an speed control electric circuit box which has a relay, a buck boost converter,a motor pump speed controller, potentiometer and a switch. The pump is powered by a 50W Solar Panel .The negative connection from the panel is connected to the relay, the positive goes to the switch. The relay determines the voltage for the buck boost converter .It activates on a certain voltage we set and then powers the buck boost converter. The buck boost converter will keep a constant voltage no matter what the voltage the solar panel is putting out. It is then connected to a 15 amp motor pump speed controller and a potentiometer which is used to control the voltage of the bilge pump motor. The 12V 500GPH bilge pump is connected to the motor pump speed controller. In order to test the unit, we place the heater near a pool to heat it. The bilge pump is submerged into the pool which is then connected to the heater with help of a PVC hose. The output pvc hose is returned with heated water back to the pool. The water reaches upto 140 F based on our test. https://www.youtube.com/playlist?list=PLbzeOtpXZbGiesna9w4eLuGzWvCQah1-h
- How to turn Dirty-water/Salt-water to a clean fresh drinking water by building a simple Water distillation systemThis project goes into the build a simple Survival water purifier that can turn salt water /sea water into fresh drinkable water .This purifier is portable, easy to make and is very inexpensive. It works by the principle of desalination .When sea water/ salt water is heated to its boiling point, the water turns into steam which leaves the salt behind. Condensing the steam back into water ,it is purified. The materials you need to build this desalination unit are a simple non insulated stainless steel bottle with a steel lid , copper tubing , stove or heating source, bottle for collecting the condensed water, soldering unit, right angle compression fiting. The condenser of this desalination unit is made from one quarter inch copper tubing. Remove the lid and the gasket from the bottle . A hole is drilled using a drill press at the top of the lid to accommodate the quarter inch copper tubing . Before soldering the copper tubing , clean the surface of both copper and the stainless steel lid with the help of a sandpaper. The copper tubing is pushed through the hole just enough to stick half an inch from both side. It is then soldered securely in place. Once this is completed , the silicon gasket is then re-installed in the lid and lid is screwed back on to the bottle. A right angle compression fitting is pressed into the lid at the copper tubing opening . The extension tube at the other end of the compression fitting is removed and replaced with a rubber gasket for better seal for the lock nut. The copper coil for the re-condensing the steam when the water is boiling is made by wrapping the copper tube up tightly against the stainless bottle . Eight or nine turns of the tubing is ideal. The ends of the coil are bend outwards so that when one end is pressed into the fitting on the bottle, the other side will be sticking straight out. The salt or sea water is added to the bottle and reattached to the lid which is hanging over a heat source such as a wood stove or camp fire. The other end of the coil is placed near a collection container to collect the distilled water. To produce more condensed water out of the copper tubing ,we need to cool it down. Otherwise the production of steam will outweigh the production of the condensed water. To cool the copper tubing , wet put a wet piece of cloth soaked in cold water and wrap it around the coil or dip the whole bottom half of the copper coil into a vessel filled with cold water. https://www.youtube.com/watch?v=PT6cjp_zThw