Pretty much everyone around the world stores power in batteries.
The battery industry is a large and growing industry.
So, the batteries must have evolved so well that they are super efficient at storing and discharging power, correct?
Well, not exactly!
Storing and discharging power using batteries can result in a loss of up to 30% of the energy supplied to them.
This is because of the energy loss that happens when you convert energy from one form to another. In the case of batteries, we convert electrical energy to chemical energy during charging, and convert chemical energy back to electrical energy during discharge.
There are hence two stages when energy conversions take place, each contributing to energy loss.
The highest loss usually happens during battery charging – a significant amount of energy is lost as heat during charging, which in fact warms up the battery!
30% is a significant amount of loss. Thus, unless you really need to store electricity in a battery, it might not be an economically smart thing to do. Even when you need to store electricity in batteries for emergency back-ups, it will be a good idea to choose an optimum sized battery back-up.
I have seen so many of rooftop solar prospects keen on having batteries. Once I explain to them the total cost of storing the solar power in batteries, only very few of them eventually opt for them!