Best Batteries for Solar Power Inverter and Wind Powered Home Generators

What are the best batteries for solar power inverter and wind powered home generators?

We look at the gel cell battery as best batteries in series or parallel renewable energy systems and why affordable deep cycle marine batteries could be a good option.

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Just as important as your choice of wind or solar power inverter for your solar energy photovoltaic or residential wind mills is your choice of battery for energy storage.

WHY DO YOU NEED BATTERIES?

Solar or wind powered home generators produce energy intermittently – either when the sun shines or when the wind blows, depending on the system. Often you will need to use the energy they produce when there is none being generated by your system.

This is why you need batteries – they act to store the energy from your alternative power system ready for use whenever you need it. While the wind is blowing or the sun is shining your renewable energy system will serve as a battery trickle charger, topping up your battery bank with energy – hopefully enough to compensate for the power you draw out of the system as electricity.

However, after more than a few days of low wind or feeble sunlight your batteries are likely to run flat. Obviously these sort of conditions could occur several times a year. That is why choosing the best batteries is so important!

Of course none of this is any good to you at all unless you are able to convert the 12 or 24 volt storage of your battery bank into mains voltage by choosing the best power inverter for your situation – whether it be a
wind or solar power inverter.

WHAT ARE THE BEST BATTERIES?

Best Batteries Type

There are generally two types of heavy battery on the market: the normal car or truck batteries, and the gel cell battery.

The main difference? Your automobile battery has acid and water in it as a solution, whereas in the gel cell battery the acid is immobile and resides in special gelified webbing.

Unlike a traditional wet-cell lead-acid battery, the gel batteries do not need to be kept upright (though they cannot be charged inverted), there is no electrolyte evaporation or spillage (and subsequent corrosion issues) common to the wet-cell battery, and they have greater resistance to extreme temperatures, shock, and vibration.

The implications of this are that your automobile battery or truck batteries are easily damaged by being repeatedly run flat.

The gel cell battery however is designed to be run flat repeatedly and recharged to their full capacity – over and over again, as often as required.

Your normal car or truck batteries would have a very much reduced life if used in this way so are not suited to renewable energy systems. However, deep cycle batteries have a lifespan of approximately 10 or 15 years under these conditions.

Gel cell battery systems sold for alternative energy arrays are often very expensive. You might save a lot of dollars by buying deep cycle marine batteries which are also a gel cell battery and are for this reason among the best batteries for renewable energy systems.

Best Batteries Capacity

Batteries storage capacity is rated in amp-hours (AH). For example, a car battery might be 35 or 50 amp hours, while a deep cycle gel cell battery used for alternative energy systems should have a minimum of 150 amp hours and possibly up to 500 amp hours.

Take a 150 AH battery as an example: it will allow you to draw 1 Amp from this battery for 150 hours, or 150 Amps for 1 hour, or 30 Amps for 5 hours… Get the picture?

To increase the storage capacity of our solar energy photovoltaic or residential wind mills systems we create banks of batteries. Simply put, the more batteries you have connected in parallel (ie positive to positive, negative to negative), the greater your energy storage capacity. All these batteries must be the same voltage!

For example:

Two 150 AH batteries connected in parallel will give you 300 AH – that is 150 AH plus 150 AH. If you connected 3 of these same batteries in parallel you would have 450 AH etc etc. This is how you can increase your storage capacity at any time – just add more batteries in parallel.

So as your energy requirements grow and the generating capacity from turbine or solar is not keeping up with your demand, you can store excess energy in your battery bank for when you need it.

Best Batteries Voltage

Either 12 volt or 24 volt batteries may be suitable for all sizes of solar energy photovoltaic panels arrays, selected to match the particular specifications of the system in question.

In this respect, wind powered home generators vary according to size. For residential wind mills elec up to 500 W output capacity, 12 or 24 volt batteries may suffice.

Larger wind powered home generators however may put out 120 V which would need 10 x 12v batteries connected in series. Connecting batteries in series increases the voltage by the number of batteries x the voltage of the batteries.