Off-grid Power Supply System for a Country House

The off-grid power supply system for a country house is designed to ensure uninterrupted power to equipment and household appliances during planned or emergency power outages. It acts as the final guardian of your devices.

The off-grid power system consists of a range of specialized equipment. The main 'combat' units in the design are uninterruptible power supplies (UPS).

Many users confuse the uninterruptible power supply system with a system using a backup power source. These are not the same. The UPS system is intended solely to keep equipment running until the backup source, such as a diesel generator, is started.

If there is no backup power source in the country house, the system’s runtime must be sufficient to complete data processes and safely shut down all equipment and household appliances. The autonomous operation time is determined by design requirements, but typically does not exceed a few minutes.

Implementing Off-grid Power Supply

To properly set up an off-grid power system in a building, you must assess architectural features, reliability requirements, total load capacity, equipment placement, and other factors determined by the client. Let’s examine two historically established methods for building reliable power systems.

Off-grid Power Supply Options for a Country House

• The first option involves dividing power supply into consumer groups. Each group has its own UPS. Equipment in these groups is grouped by location or function. If one UPS fails, only its group will go offline; the others continue operating. When equipment in a group increases, and thus power demand grows, you only need to replace the UPS. Note that since each UPS is loaded differently, the autonomous runtime for each group will vary.
• The second option is to power the entire country house from one very powerful UPS. This approach allows more efficient use of installed equipment capacity and battery storage. It also enables flexible control over autonomous operation time by disconnecting less critical loads. However, there is a drawback: if the UPS fails, all equipment will be disconnected.

These pure configurations are rarely used in practice. Instead, a two-tiered system is typically implemented, combining both approaches. The main idea is to isolate the most critical power consumers, who will operate on small-capacity UPS units—so-called 'second-level' power sources.

Less critical loads and second-level power sources are combined into a centralized system for the entire country house and connected sequentially to the first-level UPS. As a result, during a power outage, devices in the 'first group' will stop working first, while the most critical equipment in the 'second group' will continue operating for some time.

Protecting Against Equipment Failure

Finally, it should be noted that despite manufacturers’ claims of reliability, failures or malfunctions in UPS and off-grid power systems are not uncommon. And as Murphy’s Law states, it will happen at the most critical moment. Therefore, it’s wise to consider building a redundant off-grid power system. Each main UPS should have a backup unit. While this option is the least cost-effective, it is, according to experience, the most reliable.