How do I power a roadside ITS site with no mains connection?
A solar-hybrid DC system: PV array sized to the worst-month resource, LiFePOâ‚„ or gel storage sized to the required support time at the coldest expected temperature, MPPT charge control, and a thermally managed cabinet meeting the internal temperature range. Two things determine whether it works. The physical fit, cabinet and base footprint kills more roadside retrofits than any electrical parameter, so measure before you specify. And the thermal design, per I3. A solar ITS site is not a smaller version of an off-grid house; it is a temperature-controlled enclosure that happens to have a solar array on it.