Skip to main content

How to size a Solar Panel & Battery

Having developed small led lights I wanted to set up my own home lighting with some of these. From that experience I want to put this information up here for someone who wishes to use slar pv for his home.
  1. Start with the load - How many lights will you use - In my case each Light is either 1.5 watts or 2.5 watts. Let us take the total load in watts as X.
  2. You may want to use this load for Y hours a day.
  3. Calculate the Solar Panel required with a simple formula: Panel required = 2*(X*Y/6) for regions between the two tropics and = 2*(X*Y/5) for regions away from the two tropics. Notice that the difference is the figure 5 in place of 6 - you may take anything in between for regions closer to the tropics.
  4. The Panel size that you arrive at in step 3 is to be rounded off to the nearest available Panel. Remember we are talking here of 12 Volts Panels which usually have 36 cells in series. Let us say you arrive at Panel size of A watts. This is the size you will use.
  5. Now about the Battery: Your Panel size is A watts. Minimum Battery capacity required will be = A*12/17. The unit for this is AH. It is always preferable to use a higher battery capacity; hence round this figure to the nearest HIGHER capacity commercially available.
  6. One important point - I sometimes prefer to work back ward starting from battery capacity, since some capacities are very common and I prefer to use these - They turn out to be the most cost effective & they are likely to be fresh from factory (rather than ones that have remained on the shelf of the dealer - which is not good for the battery).

Popular posts from this blog

Multimeter - Learn to use for Voltage measurements

 https://youtu.be/k-Ib9f8CTGA

USB Meter - For Measuring Capacity of a USB Power Bank & Other 5V Devices

You have bought a power bank and are wondering if it really measures up to the advertised Capacity? Check with this Power Meter. You can connect it to any USB Power Source like your Power Bank. It will Show you the Output Voltage of the Power Bank - This should be 5V On the USB Female side you connect your Load. You can then see the Current that the Device Consumes. Leave it on for a while and it can give you an indication of the Power Consumed.  This is also the Power delivered by the source (Could be your Power Bank) It measures Voltage & Current - Power = Voltage x Current (For DC Voltages like this one) The Total Energy that can be delivered by your Power Bank = The Capacity of your Power Bank. Energy (Or Capacity) is the ability for the Power Bank to give X Watts for T Time before it runs out of juice. Hence TIME is the factor that comes into play to measure the Total Energy that can be delivered by your Power Bank or The Capacity of your Power Bank Capa...

Annunciator

Design & Development of Annunciator . For a California based Company redesigned their annunciators around modern technology. The annunciators could handle 1 to 128 input modules with inputs to display from 8 to 1024 zones. The original full analog design was simplified with a single main PCB with a powerful microcontroller and multiple smaller PCBs with smaller microcontrollers, Analog & Digital inputs and outputs. PC based Software was developed to configure the system for multiple parameters. The duration of the project was 8 months.Test jigs were replicated at both places (USA & Goa, India).