How to Choose an Off-Grid System for Container Homes

An off-grid container home system consists of four main components: solar panels, an MPPT charge controller, a battery bank and an off-grid inverter. Selecting these components so that they are compatible with each other and correctly sized is the foundation of a long-lasting, uninterrupted system.

It is especially critical that the charge controller is chosen to suit the open-circuit voltage of the panel array and the nominal voltage of the battery bank; a wrong match can lead to both efficiency loss and a shorter equipment life.

Battery capacity is calculated from the household's average daily energy consumption (kWh), the desired autonomy (number of cloudy days) and the battery's permitted depth of discharge (DoD). Thanks to the high depth of discharge of lithium batteries, the same autonomy can be achieved with a more compact battery bank.

Since space is limited in container homes, our engineering team analyses your consumption profile (lighting, refrigerator, heating-cooling load) and recommends a battery capacity that fits your needs exactly, neither oversized nor costly.

In winter, shorter sunshine hours reduce panel production noticeably compared with summer. For this reason, the panel power in the system design is determined based on the month with the lowest irradiance of the year; otherwise an energy shortfall may occur in winter.

For users who want extra assurance, designing the panel array somewhat larger for winter or planning for a supporting generator integration are approaches recommended by engineering for uninterrupted use in all four seasons.