Deep Cycle Batteries

Deep cycle batteries are the center of every off-grid renewable energy system. Most renewable energy sources produce electricity instantaneously - but intermittently. The sun sets, the wind stops, the stream dries up - but a deep cycle battery bank stores what went unused of that instantaneous power so you can have it for later. Batteries provide the consistency needed for comfortable off-grid living.

Everything comes and goes from the deep cycle battery bank, so your batteries will be working hard. You can help protect your batteries by regulating their charge with a charge controller and overcurrent protection and keeping tabs on them with a system monitor, but they do wear out over time. Real Goods has built renewable energy systems since 1978 using all kinds of batteries, and today we carry what we consider the industry's best for deep-cycle, off-grid use.

"Batteries are like the muscles of your body - they need some exercise to stay healthy, but not too much or they get worn out at an early age. We've found it’s best to aim for 3-5 days' worth of battery storage. Less than three and your system will be cycling the battery deeply too frequently, which will shorten the batteries' life."

Solar Living Sourcebook 14th Edition
Chapter 4: From Panel to Plug