Battery for your solar PV rooftop plant
We all know that solar is an emerging market specially in the Asian countries. Most of the nations in Asia region are developing nations. In these countries, you can easily find rural places where electrification is really poor. Solar, now days, is the potential and may be the only solutions to habitants of these areas. But solar don’t generates electricity in night. To fulfill their needs in night, storage is very much required. In this article, we will share some information about the various battery options available in market and their pros and cons. There are many types of batteries are available in market, however in this article we will only talk about the some potential or commonly used batteries.
Three types of batteries may be used for the storage solar power namely Lead Acid, Nickel Cadmium (NiCad) and Nickel Iron (NiFe). Lead Acid type batteries are the first choice of most of the users. Obviously there are sufficient reasons behind its popularity. These batteries have reasonable long life. Standard deep cycle golf car battery last for around 3-5 years. Intermediate quality batteries life span is around 7-12 years. Industrial batteries can last as long as 20 years with moderate care. Even the cost of ownership of lead acid batteries is low.
Nickel Cadmium batteries are alkaline based where positive part is Nickel and negative part is Cadmium. These batteries generally have efficiency of the order of 65-80%. The cost of these batteries is very high and also disposal of these batteries are costly as Cadmium is considered as very hazardous material. These batteries have long life in ‘chronological term’ but these cannot with stand many charge discharge cycles. Hence, there are good for the backup or emergency purposes.
Nickel Iron batteries probably have longest life span. Cathode of this battery is made of Nickel and anode is made of Iron. Potassium hydroxide is used as the electrolyte. In spite of a big positive fact of very long life, there are some crucial negative facts too. The efficiency of this type of battery is very low (nearly 60%), self discharge rate is quite high, there is high internal resistance leads to large voltage drop and some more. These batteries cannot be used where system depends on stable voltage.
In nut shell, considering the factors like life span, cost, maintenance and environmental friendliness, the best choice of battery for renewable energy sources is Deep Cycle Lead Acid batteries.
Written By: Gaurav K. Sharma