Project Log #4: Finally, Some Progress...

A project log for The Scooterbine

Renewable energy from unwanted, unloved motors, and a mean scooter.

Sam GriffenSam Griffen 08/09/2020 at 10:460 Comments

So, I haven't updated here in a while. I haven't really had any spare time, so this log will cover all the progress I have made in about a month.

First up, I put together a PCB for mounting all the anemomenter components. This is shown below, and the circuit for wind speed measurement is yet to be tested, hopefully I can test that in the next couple of weeks.

I have uploaded the KiCAD project for this board to the project files. Essentially a TC4056A LiPo charger module is used to take power from a small solar panel, and manage the charging of a small LiPo cell. This is obviously not optimal, as no maximum power point tracking will be performed, so likely output will be abysmal. However, this is an easy initial testing stage. Battery voltage is then converted to 3.3v for an ESP32 module. Below this is the circuit for interfacing with the anemometer that I detailed in my last log.

My plan was to test the power system for the anemometer, but I realised that my setup as it is won't cut it. I have a small 1s LiPo that I want to use (For ease of charging), however what I failed to realise was that the only buck converter I have on hand requires a minimum input of 4.5v when stepping down to 3.3v. As a single cell LiPo can supply 4.2v at it's best, this didn't seem like such a good solution anymore. I have ordered a small buck/boost converter that should be able to be dropped into the PCB I have made. 

I believe that once I can get 3.3v out from the battery, regardless of the battery voltage, I should be good to start designing a housing. Before then, I need to complete testing on the actual windspeed sensing capabilities. Externally powering the module, and writing up some code to read the anemometer should be enough for a proof of concept.

Secondly, I have done some thinking, and based on the area around my house, a horizontal axis wind turbine may be better than the vertical axis I had in mind initially. I have started sketching up some designs for a gearing system to mount to the scooter motors, and done some sketches for how I might setup my nacelle.

Based on this, I will probably need to add some form of windvane to the anemometer setup. This can be a next step after getting the wind speed data logging working.

Overall, a pretty useless progress update really. I have a university holiday coming up soon, so I am hoping to get stuck in and finish some things here.