Two posts ago, when showing how to do d3 charts, I mentioned that in the graphic presented smart charging was already visible in action. I will present another example from the last weekend where I had the chance to gather more data with the implemented algorithm. The inverter data summary is also updated and looks better. It includes a new chart I thought out to visualize the different parts of energy consumption and production.
This chart shows energy consumption (in red) and production (yellow). The bar chart on top shows the total energy consumed and produced over that day (x = 0 to 22.97 kWh). I wanted to include also the values for what energy came from the grid (red without yellow overlapping), the energy used from own production (yellow until the overlapping of red ends) and the energy feedback to the grid (last, only yellow part). The relation consumed (18.54 kWh) to the part that needed to come from the grid (3.18 kWh) gives the negative autonomy percentage. The autonomy is with almost 83% very good for that day. The detailed chart below shows when that was achieved. The consumed energy is again presented in red (dots and lines) while the produced energy is shown yellow (vertical bars). These values are the hourly Watt output presented in five minute batches, since that is the rough summary smartics saves. This also means that the values of the y coordinate would have to be divided by 12 to show the real output over each five minute summary. For the relation on the chart it does not make a difference. It is easier to understand like shown though, as the output at any given time is presented that way.
But what is there to actually see? The option smart charging was activated the whole day, except for a time between 11:30 and 12:00 where I tested something in the application until 15:00 where I stopped it for further tests. Apart from that about 13 kWh of the overall consumption were used for charging. As soon as there was enough excess energy at roughly 9.30 the parameters on the charger were automatically set accordingly to hand over excess energy to the car. This worked quite exact as it can be seen by the overlapping of the red dots and the top of the yellow bars in the chart. One exception was where cooking before lunch around 11:30 was involved which produced some additional spikes.
All in all I can say that this, simple form of smart charging, works very well. Even though the energy to charge the car in this example is not expensive, it still saved 20% of the cost since it came directly from the energy produced by own solar panels (2.6 of 13 kWh). Nevertheless, this was an exceptional nice day for the winter season and perfect conditions since the car was at home basically the whole day. This way about 80-90 km can be driven powered purely by the sun and smart code.
Btw. I already added some more features for version 0.1.4 of the application including the saving of charging data, a current energy chart that refreshes automatically (showing energy consumption, production and feedback in realtime) and smaller responsive improvments!
— Raphael
Beta solutions e.U. 