Just a quick blog about charge / discharge times.
Battery is 28V 4KWh LifePO4.
Inverters are 2 x 500W and 1 x 1KW. (500W inverters seem to supply about 350W, 1KW supplies about 700W, so all together they can supply roughly 1.4KW, although the power they supply does drop when they get warm/hot)
Had bright sunshine in the mornings the past few days, charging the battery up fully in ~5 hours.
System switches to discharge mode when the output from solar panels stops, ~7pm.
With a full battery the system can supply the house (upto 1.4KW demand) from 7pm to ~2am, so runtime is ~7 hours.
Usual demand during that time:-
* 7pm to 10.30pm: 1KW : 3.5KWh
* 10.30pm to 11.30pm: 750W : 0.75KWh
* 11.30pm onwards: 500W : (KWh upto 2am) 1.5KWh
Total KWh: 5.75KWh
Which is interesting.
My guess is the inverters drop down to about half their rated power when they're hot, or the Wattson is overreading consumed power quite a bit.
I'll know which when I add the extra bits to monitor the power going into and out of the solar storage system, and the code to log the readings (from everything) to a file on an SD card.
Right, the battery is full again, time for me to pull the two little breadboards to bits and rebuild them on a bigger one so I can add the third current sensor and an RTC.
No comments:
Post a Comment