Off-Grid solar systems work in much the same way as hybrid systems do except they are not connected to the grid. They are 100% self-sufficient and cannot take grid power occasionally when batteries become fully discharged. For this reason it is better to oversize off-grid systems so that they are able to generate enough energy even during inclement weather. It is also good practice to add more battery storage capacity than usual to ensure you don't run out at night and during inclement weather. Off-Grid solar system are consequently the most expensive of the 3 types.
Special attention also needs to be paid to inductive loads such as water pumps. The current in-rush when the pumps start cannot be absorbed by the grid in an off-grid application; the inverter has to be able to handle the sudden surges on its own. We can power pumps up to 3HP with the use of a special single phase soft-starter device. Single phase off-grid inverters range only between 5 and 6kva so they are suitable for up to around 30kWh of energy consumption per day with less than 5kW of load. We do offer larger off-grid systems from 10 to 100kW but they are 3-phase AC with high-voltage battery banks.
The most important thing to consider though when choosing an off-grid system is the battery chemistry. Most solar installers in the Philippines only offer obsolete lead-acid type batteries which are quite hopeless in off-grid applications. You need very reliable batteries in off-grid applications since you depend on them entirely 24 hours a day. They also need to last for decades with high depth of discharge capability. We offer only the latest generation Lithium-Iron (LiFePO4) batteries from Alpha-ESS for our hybrid and off-grid systems. Click here to learn more.
We specialise in off-grid systems in fact our owners house is completely off-grid and runs the air conditioning 24 hours a day as well as 2HP water pump with water treatment facility; they never run out of power even during typhoons and use around P11,000 worth of energy per month. We have several off-grid customers around Northern Luzon who know enjoy ample, reliable electricity where there was none hitherto.
Please contact us so we can discuss your requirements and design the ultimate system for your self power generation needs. Our product range goes from 5-100kva with 3kWh to 1MWh of lithium battery storage. We can do anything from a small farm to a full scale micro-grid.