How do Batteries Work?
Why is a battery bank necessary? Because an off-grid system does not allow you to store electricity easily and economically. There are other ways to store electricity but they are more expensive.
Why is a battery bank necessary? Because an off-grid system does not allow you to store electricity easily and economically. There are other ways to store electricity but they are more expensive.
The more energy you consume, the bigger the storage facility you need. Buckets are measured in liters or gallons; battery capacity is measured in watt- or amp-hours. If the battery uses a higher voltage source for charging (like a full-strength PV array), you will enjoy a higher voltage recharge – a battery bank of 24V can record a 30V voltage when it goes through equalization charging.
An electrical load is normally required all the time to work a wind or hydro turbine. The energy generated from these sources needs to be redirected elsewhere when the batteries are fully charged. This is where the diversion load steps in.
CAUTION!
Sealed or "maintenance-free" batteries need no equalization charging.
Equalizing these batteries can cause fire or explosion.
The equalization process can be visualized as batteries being buckets with electricity being the water filling the buckets. One bucket is one battery cell.
Inverter capacity is the amount of power which can be supplied continuously by the unit. The inverter rating must be at least 25% more than the total power required by all connected appliances operating simultaneously. Multiple inverters can be series-wired or parallel-wired for the required capacity.
An inverter's surge capacity indicates how it handles short-term overload before "tripping". Surge capacity is essential to start up some large loads, especially motors that need 2-3 times their running power to get going. The start period may be very short – a fraction of a second – but it still needs to be considered.
Grounding is used to dissipate electrical energy safely when faults occur. This is the third pin on your extension cord plug which allows electricity to flow when system insulation fails.
When purchasing an inverter, important considerations are the unit's electrical rating and the option of a "sine wave" or "modified square wave" model.
Here's what to check when selecting an inverter:
As you cannot see electricity, it is hard to confirm the exact amount of energy available in a battery bank.
The vast majority of solar thermal installations are based around solar collectors which use a fluid for thermal transfer. However, there are some designs which use air as the transfer medium.
Air collectors are just like their liquid counterpart flat plate collectors: they come in a frame that's insulated on three sides and glazed on the fourth, they have a flat absorber plate, they're of similar size to liquid-based collectors and they work in a similar fashion.