Solar batteries are considered expensive.
But, to be honest, that all depends on how you calculate the answer. Is the upfront cost expensive? Sure. Most solar batteries are expensive on the front end, but in the long run, the money you save is worth it and makes the whole initial expense somewhat forgettable.
Investing in a good solar battery means that you will be getting off the grid with your solar system. Why have you not done this already? If you’ve got the panels on the roof, then you’re halfway there. Instead of running off-grid during the day and going back to the grid at night because the sun has gone down, store your excess power during daylight hours instead of selling it back to the utility and make use of it yourself at night.
Capacity, power and depth of discharge are all terms we hear when talking about solar batteries. You should become familiar with each so that you have an idea of what to ask for when shopping your solar batteries. Capacity is how much electricity the battery can hold, i.e. liken it to how many millilitres a glass can hold. Power is how much output the battery can supply at one time. High output power ratings mean it can power a lot of items at once. Lower capacity ratings mean less time running those appliances.
The depth of discharge has to do with the battery itself. Solar batteries keep part of their charge at all times due to the materials they are made from. So the depth of discharge is how much you can run it down or how much of the power in that battery, you can use.
Much like cell phone batteries, solar batteries are guaranteed by cycles (charge, use, recharge). Eventually, they lose their ability to hold a charge but that takes a long time, so when shopping batteries, look at it this way, small capacity, large power rating equals running everything but not for very long. Large capacity but lower power rating means you can run a few things a for a long time. Figure out where your priorities lie and go forth from there.
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