Off-Grid Solar Systems
As it stands, the installation of a home solar system is not sufficient to allow most home owners to satisfy all of their daily energy demands. Instead, solar power is used as a means of reducing their dependency on existing power from their electricity provider. Going ‘off-grid’ would mean relinquishing the ability for you to call upon mains electricity when your solar system is unable to generate the required power, such as at night. In order for going off-grid to be feasible, it’s necessary to install solar batteries to store your excess solar energy.
Using solar batteries to store energy
With off-grid systems, you don’t have the luxury of being able to rely on mains power when your solar energy reserves run out. This is where solar batteries come into play. With solar batteries, it’s now possible to store the excess solar energy generated by your system and utilise these stored energy reserves when needed.
Which solar batteries are the best?
There are two major types of solar battery:
- Lead acid
Lead acid batteries have been used in off-grid systems for years and are a cost-effective solution for those seeking to install large quantities of energy. Lithium-ion batteries are smaller and lighter than lead acid batteries, last longer and also possess a greater depth of discharge. While lithium-ion batteries are substantially more expensive to buy than lead acid ones, research shows that they can provide up to 6 times more cycles than a lead acid battery.
How long do solar batteries last for?
Solar batteries typically last between five and fifteen years. Like solar panels, solar battery longevity continues to improve at a rapid pace. Learning to take proper care of your solar batteries can have a marked effect on their shelf life. Aside from proper maintenance, environmental factors can play a role in determining the lifespan of your batteries; temperatures above 32°C can cause the battery to overheat, making it necessary to reduce the charge of the battery, while temperatures below 0°C will necessitate the need for additional voltage in order for the batteries to reach their optimal charge.
High quality brands will have temperature regulation already built in, but cheaper models may not, in which case you may need to consider storing the battery in a special below-ground shelter.
Determining the size of your off-grid solar system
To determine how much energy you will need to have stored in the batteries to cover your demands, you will first need to calculate your total energy use. This is done by tallying up the energy consumption of all electrical devices that you are going to be using.
To calculate the requirements for a single device, find out its power rating (in Watts) which will be labelled on the device and multiply it by the approximate number of hours you expect to use it on a given day. This value (measured in watt-hours) gives you an idea of how much energy is required to operate it each day. Now go ahead and calculate the energy values for every other appliance and get the total. This final value gives you an insight into the output requirements of your off-grid solar system.
The greater your power needs, the larger and costlier your off-grid solar system will become. For this reason, it’s essential to use energy efficient items, conserve power in any way you can and ask yourself whether or not you really need to use a particular appliance or not.
In order to operate some devices, a power inverter may be required to convert 12V DC to 240V AC (or to 120V if living in the US or Canada). Off-grid systems require their own specific type of power inverters and their price depends on their output capacity. More powerful inverters are expensive so it’s wise to consider using DC devices where possible.
Even if you don’t go off-grid, PV solar systems will still save you money
Even if you discover that a solar energy based system is unable to support your daily household energy requirements, PV solar systems are still an excellent way to save money on your power bills. With many companies now offering no deposit solar finance packages, you can start enjoying the financial benefits of solar installations for your home or business without having to pay the full sum upfront. Many countries offer generous solar rebates and feed-in tariffs, which further enhance the appeal of getting a PV solar installation.