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Question: How to design a solar energy system?

(Posted by: mu86neer on 2009-05-03 05:35:01)

Concerning the calsulation: 1- system nominal voltage is 12 v DC 2- system nominal current is 2 A DC 3- days of autonomy are 4 days 4- daily energy consumption is 288 Watt. Hour 5- daily anticipated peak sunshine hours are 4 hours 6- cable and circuit operation losses are 0.25 ohms 7- PV panel power is 18.75Watts 8- 100 A rechargable battery. i have done some calculation but i still need to get from you. Thank You for answering

Posted by: Hecate on 2009-05-03, 05:50:55

That is a complicated issue. You can use passive solar construction by positioning your windows and solid structures to pick up the most heat at the right times. Water containers painted black hold heat. You can lay pipes in yard that pick up heat during the day. You can use solar panels, but there are still issues with that. There are some very smart guys on youtube who can give you more details. It also depends on where you live. You don't seem to be gettting much sun shine with only four hours a day. Good Luck on your efforts. Hecate

Posted by: occularis infernum on 2009-05-03, 07:16:29

I used a single 80 watt, 5 amp, 17.9 volt pv. it charged 3 1000 amp deep cycles during the day which ran a 3kw inverter. on that i ran a microwave an air conditioner and a tv individually with no probs. if you use inductance inverters and a couple of fat 80 volt 1 farad caps and a hefty diode to go to the batterys, then you can run directly of the pv and charge your batterys at the same time for usage at night.

Posted by: Dave S. on 2009-05-04, 08:38:17

There are website that can help you total up you usage, autonomy, etc. This will help you calculate the size system you need.

Posted by: Chris on 2009-05-04, 18:53:39

Can be used to decrease or eliminate energy costs, reducing our impact on the environment and saving people money in the process. If you wish to design your own solar electric system, it pays to be prepared. Step 1-Determine whether you will need to tie your solar electric system into the existing power grid or you wish to design it for use off the grid. This will depend on your precise location and how near you are to a power line. Step 2-Calculate how much sun your area gets, and whether there are any obstructions which may cast shadows on your solar panels. Step 3-Perform a power load analysis to determine what your electric needs will be. The table provided at SolarSense.com can help you calculate your requirements (see Resources below.) Step 4-Determine the output of the panels you wish to use (based on their capacity and how much sun they will receive), the battery you have in mind, and the inverter your home will require. Step 5-Compare your expected panel output with the amount of space your solar panels will require, and then compare that to the amount of space you have available. This will determine how much energy you can reasonably produce with your solar electric system, and should be incorporated into your design. Step 6-Prepare a contingency for those times when the sun does not shine enough to produce adequate power. If you are on the grid, it will mean paying for electricity through the power company. If you are off the grid, it will mean using alternate forms of electric power such as generators. Step 7-Choose your components based on what you require. These will vary widely depending upon your circumstances, but will include the solar panels themselves, mountings and means of securing the panels, conduits and wiring, an appropriate battery or generator, and an inverter to convert the panel's DC power to AC use.