Roger Haug lives on the island of Bonaire, a sunny and remote Dutch territory in the Caribbean. As the Dive Operations Manager of a large local dive resort, Roger brings both hands-on technical experience and certified electrical knowledge to the table.
Roger reconfigured his home, previously powered by a three-phase 220V/110V grid, to operate solely on solar energy. To accommodate both 220V and 110V household devices, he designed a setup where the inverter outputs 220V AC, part of which is stepped down to 110V using two dedicated transformers.
Compared to 110V inverters, 220V solar inverters are generally slightly more economical. Especially, for regions where both 220V and 110V devices are in use, Roger’s setup serves as a highly practical and cost-effective diy solar reference.
Power Source from Solar, Generator and Battery storage
Roger’s off-grid energy system is powered by solar panels, a large battery bank, and a backup generator. At the center is the POW-HVM11KW-48V inverter, which delivers 220VAC and coordinates all power flow.
His 24 JA Solar 450W panels generate up to 10.8 kW, powering household loads and charging a 30kWh battery bank built from twelve 200Ah LiFePO₄ batteries arranged in three parallel strings of four in series. This configuration delivers a nominal 52.4V, perfectly matched to the inverter.
As an additional layer of resilience, Roger has installed a 5kw backup generator that can provide temporary support during extended cloudy periods. However, thanks to the strong solar and battery combination, generator use is minimal and only required as a last resort.
Related Article:
Step Down Transformer 220V to 110V and Load Distribution
Roger’s solar inverter delivers a stable 220V AC output, which passes through a 60A fuse before reaching a power rail consisting of L1 and neutral. Then, the power is partially distributed directly to 220V loads and partially routed to a pair of step-down transformers 220v to 110V.
From there, one circuit supplies direct 220V loads, and another feeds a 40A branch into two 5kW step-down transformers, which convert 220V to 110V AC, each protected by 60A fuses, and supply two separate 110V circuits.
To ensure safety and proper current capacity, Roger replaced all key conductors during the installation process. Main connections from the inverter to the fuse box were upgraded from 2mm² to 10mm², while 6mm² cables were used for lines connecting distribution rails to individual circuits.
Additionally, the power of the generator has a Y switch, either to invertor input, or cut the invertor output and connect straight on the 220v rail. From there it powers 220 groups and the 220v input of the 2 110v coils.
💡Improvement tips:
Replacing the 220V fuses on the power rail side with an ATS (Automatic Transfer Switch) can prevent potential reverse current from the generator flowing back to the inverter circuit when the generator is connected directly to the power rail.
Appliance Loads and Energy Usage
Roger’s energy consumption is well-balanced between 220V and 110V loads, optimized to match his solar generation and battery storage capacity.
On the 220V side, the loads include a pool pump, four air conditioning units, two water heaters, and a refrigerator that consumes approximately 140Wh per hour. Typically, two air conditioners operate simultaneously to maintain comfort in the tropical climate. For hot water, a 3kW water heater runs for approximately 10 minutes per shower session. The pool pump is controlled by a timer, running twice daily for one hour each time.
On the 110V side, the step-down transformers supply power for LED lighting and occasional use of appliances like a vacuum cleaner or washing machine. When active, 110V loads range from 0.6 to 1.6 kilowatts.
Thanks to the seamless integration of solar, a backup generator, and a 220V to 110V transformer, Roger’s 100% off-grid system has been operating reliably since April 21, consistently covering his daily energy consumption of 24–28 kWh, totaling around 800 kWh per month, and saving approximately $400 per month on electricity costs.
