I am interested in what you are doing to add a solar canopy and trailer.
Me too.
I am moving slowly. Unfortunately, I have retired to an area that is indifferent-to-hostile towards ebikes. It is quite hilly, and also there is a very sparse economy so that there are only small towns connected by two-lane roads - one in each direction, and the roads have no accommodation for bicycles, let alone trikes (see my signature). The local economies here rely on people towing camping trailers on holidays. This means large vehicles piloted by city people at high speed on narrow roads often with no shoulder, let alone bike lanes.
I have some reasons to be here for a while. I'm investigating whether the next state over (Victoria) might be better for a bicycle life. Also, current world events may change circumstances in ways that make the situation more accommodating for me, but the possibility of widespread electric cars would not necessarily help - they still travel at high speed and don't increase the IQ or the integrity of the operator.
My trike has a footprint of approximately 2 meters by 0.8 meters, which matches two gleaf solar panels I have, each at 160W nominal, when mounted together. I'm thinking of making the frame to mount them like that, and then separately make a frame that holds that as a roof for the trike, or the top of a trailer. The rest of the trailer could then be low to only carry cargo beneath the panels, or higher to permit sleeping inside.
I have a Wike trailer kit which relies on me buying square tubing rails locally to define it's size. It may not be strong enough for what I arrive at, but does let me do the experiments before welding something up if needed for strength.
I also have one of the last 170W SunPower panels Grin sold before they became unavailable. If I'd bought a second, I wouldn't have also bought the gleaf panels, but this gives me options. I might mount the SunPower as the sun/rain shade for the trike, while pulling the gleaf panels on the trailer.
Local laws (Australia) don't permit me to use a motor rated for more than 250W continuous. I could manage this with a mid-drive motor using the gears, or the scheme I'm using now with a hub motor and a step-down ratio to the rear wheel (again, see my signature). My set up is simplified this way - only one motor, only one battery at a time.