Back me up! (With Batteries)
You get two types of batteries that can be used in a solar/power-backup solution, Lead Acid, and Lithium-Ion
Lead-acid batteries are the most common type of batteries in use today since they are relatively inexpensive, with can be found anywhere. These batteries are an easy entry point for people who want to build a solar system but don’t have much experience. They have 2 main disadvantages which are that you can only use 50% of their capacity and they have a short lifespan compared to lithium batteries
Flooded and Sealed Batteries
Flooded and sealed batteries are the most common and cheapest types of lead-acid batteries. These batteries come with a low life cycle count which can be anywhere from 150 to 300 cycles before they lose too much life span where they would then need to be replaced.
AGM and Gel
AGM and Gel batteries are particularly good for solar installations. These batteries have a much longer life cycle compared to flooded and sealed batteries and are recommended for power backup and loadshedding systems. Before Lithium-Ion batteries became cheaper for normal consumers to install, these were the de-facto batteries that you needed to use for solar installations.
Lithium batteries are your main type of battery that should be used with any solar system as they can manage all types of abuse, from being drained to nearly 0 to high discharge rates, all while maintaining a high cycle count, usually over 3000 cycles and even going as high at 6000 cycles while remaining within warranty.
What brands do we recommend?
- PylonTech - PylonTech is a manufacturer of lithium battery energy storage systems in China. The product portfolio of the company includes an Energy storage battery system, a Portable power bank, Communication backup power system, Batteries, and Others.
- Dyness - Dyness is a Battery Management System (BMS) which can monitor and balance the modules of lithium batteries in real-time. In addition, it can protect the battery from overcharge, over-discharge, short circuits, etc.
- Hubble Lithium - Hubble Lithium battery is a high-performance lithium battery and is used for Solar inverters, and UPS backup systems. Compatible with a large range of solar inverter systems. The integrated BMS manages the cells and takes care of the battery pack. Delivers 4800Watts continuously per battery.
- Freedom Won - Freedom Won offers cutting-edge lithium storage with a quantum increase in service life and operational efficiency, at a fraction of the lifecycle cost compared to other energy storage solutions.
- Omnipower - The OMNI POWER CT is an electronic CT with zero-moving parts. This technology provides not only significant cost savings but also improves the safety of the product for end-users and installers.
How do I calculate the size of my battery bank?
Before you start sizing up a battery bank, one of the most important activities to do is determine how long you want the battery to last and what kind of load it will be under.
An easy way to calculate your load is to look at the appliances that will be running when there’s no power and see what their power draw is, an approximate to each appliance is listed below:
- TV – 100W
- Soundbar – 100W
- Fridge/freezer – 150-200W
- Router/modem – 25W
- Laptop – 50W
- LED Light bulb – 10W
- Desktop PC – 200-500W (depends on your configuration and what you are doing with it)
These are just estimates - your power draws may differ from these examples.
You would then need to add up your power draw and that will tell you how much power you will draw for an hour and multiply that number by how many hours you want the system to run for e.g., look at the following example
Tim wants to have power during loadshedding at his home, which means needs power for 2 and half hours. Tim wants his TV, 4 LED light bulbs, fridge, laptop, and router powered during loadshedding. So, his calculation would look like this:
TV – 100W
Router/modem – 25W
4 x LED Light bulb – 10W
Total = 365W Per Hour.
Tim would therefore need a battery bank of at least 912.5-Watt Hours. We will round this figure up to 1000-Watt hours to build our battery bank
What about the warranty?
Battery warranties are more finicky because each manufacturer has a different warranty method on how they will evaluate their product. Such as Pylon will warranty their battery for 6000 cycles or 10 years, whichever comes first. They also guarantee that the battery capacity will not be less than 80%. There are many more factors influencing a battery’s warranty, but these are the main points to focus on when choosing a battery.