Solar Trailer
This is an experiment, stimulated by the COVID-19 pandemic, for exploring a more independent and sustainable lifestyle. The trailer has its own electrical energy source (solar) for induction stovetop cooking and for charging computers and phones, and stores enough food and water for about one person-month. In an emergency (with sufficent sunshine) it will add a few miles of range per day to the plug-in hybrid tow vehicle. It also has a sink with a cold-water tap for washing clothes, dishes, and even people.
Details
The electrical system consists of a single 330-watt solar panel, an MPPT charge controller, two small AGM batteries, a 1000W (continuous rating) pure sine wave inverter, DC and AC circuit breaker boxes, five pairs of GFCI-protected AC outlets, one pair of non-GFCI AC outlets, two Bluetooth-controlled LED interior lights, a local WiFi router, and a tiny Raspberry Pi computer for solar data acquistion.
Performance
The current system is capable of charging the tow vehicle, but only at the car’s 120V/8A setting and only for about 15-20 minutes at a time (since the trailer's battery bank is only 24V and 35Ah = 840Wh, or 420Wh usable). This is mainly for emergencies, until the system is scaled up with larger batteries and/or additional solar panels.
Upgrade
In July of 2023, the trailer's batteries were upgraded to 55Ah, for a new energy storage capacity of 24V * 55Ah = 1,320Wh, or 660Wh usable.
Future
In the midday sun on cool spring or fall days, three 415W panels should be sufficient to charge the vehicle for several hours, without draining the trailer batteries at all. In ideal conditions a larger system like this could conceivably give the car a maximum of 6kWh per day (assuming adjustable, tilting panel mounts), which should be good for about 14+ miles with the trailer and 25+ miles without. These distances, particularly the one with the trailer, would require driving at 55 mph or less.
