Comment by RainforestCx

Great question, and one that’s of particular importance in our design. Many IoT-type systems make use of on-device data analysis in order to minimize the most energy intensive process: data transfer. Our hardware focuses instead on getting full audio streams up into the cloud in near-real time, continuously, 24 hrs a day. This requires an exceptional amount of energy, as well as the ability to pool energy to continue operating at night and during poor weather. That said, we’ve really overcompensated on energy capture and storage—we operate under the assumption that we should be able to support 1.5 watts of continuous power draw 24hrs a day (normally it’s closer to 50% of this). But that means we try to be able to generate 35-40 watt-hours of solar energy for each day (on average). This is further complicated by the shady/infrequently lit conditions of the tree canopy. So, when direct light shows up (sometimes for moments or minutes only) we want to be able today capture as much as possible (high charging amperage and ample solar panels). Our batteries (LiFePO4) must be able to support this, and not decline over 1-2 years of use being fully discharged and recharged each day). We also designed a type of solar array that is specifically intended for the tree canopies. If this is interesting I’d be more than happy to elaborate more!