DIY ESS - Solar & Energy Storage under Grey Sky ...

We always see pictures and videos of Solar panels under a great sunshine, but to tell the truth, it is not always like this ...

Here are Energy Monitors, Graphs, Pictures and Video of the bare reality of what happens when the sun is hiding

Sometimes the solar generation is rather low - with my 1000W solar install - but still something is coming out of it steadily during the day; Now fall is here, sun starts producing around 9AM instead of 7AM, but around 200-250W all day long when the sky is grey

Fo rnow, no heating is required yet, and the ESS I built is doing the job: Capturing any excess/surplus of power into the Battery pack for later use and always keep the Net Usage (= Usage - Generation) as close to 0W as possible

Whenever a washing machine water heating cycle comes on, the ESS stops charging the Battery pack and uses the Energy saved in it to push it back into our home grid, reducing the usage from the utility company. It is really a Peak Shaving device  

As you can see, the ESS keeps the Net Usage around 0W; That's the yellow line on these graphs

Here we can see that the early morning consumption is not covered by the ESS anymore like it used to be during summer : The Battery pack voltage is too low and no Power will be drawn from it until it reaches a certain level with Solar; Also, at night, the sun setting earlier, I often see the SMA inverter quit around 6PM now especially when grey, and the ESS quicks in right away to supply all the household Power for lights, TV, computer, etc ... until the Battery is back to low and the ESS then quits too - If sunny the whole evening usage can usually be covered - 

When Power is required, the ESS switches from Charge Mode to Grid Tie Inverter Mode to help supply this additional Watts to our home

This video shows an example of power pushed by the ESS into our home while cooking lunch

As we go deeper into fall and heating will soon be on during the day, I think I will use the Forced Charge Mode on the ESS to start charging during off peak hours (TOU), at night, and start the day with a Fully charged Battery pack, ready to crush it !  :-)