Solar Offgrid Rumah Kebun Tengah Hutan

DIY Off-Grid Solar System for a Garden House

Rusydi Bahar presents a DIY off-grid solar system for a garden house in a forest. Extending the utility grid (TNB) from the main road would cost more than RM40,000. The system is designed to provide basic home comforts, including refrigeration, fans, and reliable water pressure. The stated cost of the setup is about RM8,000.

System Components

• Solar panels: Three 550 W Jinko panels, for a total capacity of 1,650 W. They are wired in series to keep current lower and allow the use of 4 mm² cable. The panels are mounted on a frame suited to the house’s hillside location.
• Inverter: An MPP Solar 3024 GW all-in-one unit that can operate off-grid or in a hybrid setup, but cannot export electricity to the grid. It provides up to 3,000 W continuously and has powered tools such as a welder and grinder. The speaker describes it as an efficient high-frequency inverter, but cautions against running loads above its rated output for extended periods. Built-in Wi-Fi provides energy-generation data, though the app refreshes about every five minutes rather than showing real-time readings. The AC input can switch to TNB power when the battery is low.
• Battery: A 24 V, 280 Ah LiFePO₄ (lithium iron phosphate) battery, mounted close to the inverter to reduce the cost of thick battery cables. The speaker gives a theoretical lifespan of around 3,000 full cycles. He recommends a battery-management system (BMS) with active balancing and protection against voltage faults and cell imbalance. He contrasts LiFePO₄ batteries with gel batteries, which he says have fewer cycles at full depth of discharge.

Safety and Installation

The speaker stresses that DIY installations still need electrical protection. He recommends:

• A breaker and surge-protection device (SPD) on the wiring between the panels and inverter.
• A large breaker between the battery and inverter.
• Breakers and isolators between the inverter and distribution board.
• Grounding.

He also cautions that inexpensive inverters may have current-leakage issues.

Solar-System Sizing

The speaker demonstrates an Excel solar calculator he developed, with options for 12 V, 24 V, and 48 V systems. Users enter appliances, their wattage, and hours of use. The sheet estimates battery capacity, solar-panel capacity, inverter size, cable sizes, and breakers.

His example includes fans, lights, a water pump, Wi-Fi equipment, a refrigerator, and a phone charger. It estimates approximately 311 Ah of battery capacity, 1,867 W of panels, and a 972 W inverter. He recommends using an MPPT charge controller rather than PWM.

The speaker says accurate load calculations help prevent undersizing the battery, panels, or inverter. He reports that the garden house has not run out of power and says he has helped followers install systems themselves through WhatsApp guidance.

Speaker and Source

Rusydi Bahar, the video’s host, explains his own installation and demonstrates his solar-sizing spreadsheet. He also refers to installation experiences shared by followers.