The size of an off-grid solar electric system depends on the amount of power that is required (watts), the amount of time it is used (hours) and the amount of energy available from the sun in a particular area (sun-hours per day). The user has control of the first two variables, while the third depends on the location.
Iron Edison is here to help you find the Nickel-Iron battery system that is perfect for your specific needs. Because Nickel-Iron has a completely different set of operational characteristics, it is important for us to learn more about your system, your application, etc.
The size of the battery bank required depends on the storage capacity required, the maximum charge and discharge rates, and the minimum temperature at which the batteries will be used.
Temperature has a significant effect on most types of batteries. At 40°F they will have 75% of rated capacity. At 0°F the capacity drops to about 50%
A battery in a PV power system should have sufficient amp-hour capacity to supply power needed during the longest period of cloudy weather. If there is a source of backup power, such as a generator with a battery charger, the battery system does not have to be sized for worst-case weather conditions.
Lead-Acid battery system cannot be discharged below 50% without causing irreversible damage. The Iron Edison battery has a recommended 80% depth of discharge, and can be discharged 95% without any damage whatsoever.
When designing a power system all these factors are compared and the one requiring the largest capacity will dictate battery size.
The 12 Volt system is comprised of ten individual cells that are connected in series with each cell producing about 1.2 Volts at maximum capacity. 12 Volt battery systems are generally constrained to about 2500 Watts of input power, so sizing becomes very important. Also, there are more accessories designed for 12 V systems than for any other DC voltage.
The 24 Volt system is comprised of twenty cells, and allows you to gather energy from a mid-size solar array. These systems are great for off-grid applications where total space is limited. The 24 V system can also be used with an AC / DC inverter to power your normal 110v / 220v appliances and electronics.
The 48 Volt system is modern and efficient. Lower cable amperages translate into thinner and cheaper wire and there are fewer concerns with over-current protection devices. We recommend the 48 Volt system for any new off-grid installation.
|Operational Life||30+ Years||5 - 7 Years|
|High-rate Discharge Performance||Good||Poor|
|Thermal Danger if Shorted||No||Yes|