In the Design Area description for 4.2, it requests a system that can deliver anything between 3 – 10 kwh per day. When thinking about how this stored power would be used, it is good to refer back to the Bushlight system, and to review what those systems cater for; several lights, fans, basic appliances. However, depending on the amount of stored energy, there are guidelines on how many of these lights/fans/appliances can be utilised simultaneously.
When planning your solution, these are the questions that you should look to answer. For example, if you decide that the trailer can only facilitate a 5kwh storage system, what are the limitations of that system? How long to recharge that battery, and how large will the solar array need to be to accompany that system?
If the system is only 5kwh of stored energy, what activities can the rangers expect to conduct with that power source – just basic lighting, refrigeration, power tools? If there is a solar array that is charging the battery whilst it is in use, what are the implications on use? In your final solution, I’d recommend outlining what usage limitations there are for the system, and providing usage guides, similar to the Bushlight systems.
We’ve just answered another question in this forum that you might find has further useful information – https://ewbchallenge.org/forums/topic/mobile-solar-power-supply/
If you’ve got further questions, please do reach out.