Measuring daily insolation and efficiency

Questions
#1

I am now a donor (yay).

I have set up my weather station which also provides insolation. I really want to track insolation / harvesting efficiency over the course of the year i.e. against temperature and light levels. Unfortunately while I weather station seems to report Watts/M2 it doesn’t report total daily insolation in watt hours. Maybe there’s a way to work that out but it reports to both WeatherCloud and WeatherUndergroun and it’s own Ecowitt service.

I think I also set the ‘extended’ V7-11 channels to everything available including insolation.

Test output is the following so it seems to be working fine but I don’t see it in my output graph yet.

stationID “ID”
obsTimeUtc “2020-02-22T00:25:45Z”
obsTimeLocal “2020-02-22 11:25:45”
softwareType “EasyWeatherV1.4.4”
country “AU”
solarRadiation 796
lon 149
realtimeFrequency null
epoch 1582331145
lat -35
uv 7
winddir 223
humidity 53
qcStatus 0
metric
temp 22
heatIndex 22
dewpt 12
windChill 22
windSpeed 1
windGust 4
pressure 1023.03
precipRate 0
precipTotal 0
elev 655
#2
  1. Under the wunderground config assign ‘Solar Radiation’ to one of the extended parameters v7 - v12

image

  1. Configure the extended parameter label and units -

image

#4

To convert your Solar Radiance from your weather station to kilowatthours you need to know several things.

  1. The total area of your array in square meters
  2. The Energy efficiency of your panels
  3. The orientation of your panels both direction and tilt (if split orientations you need each orientation calculated separately then summed)
    I have done this for my system with two orientations here:
    Calculating panel efficiency
1 Like
#5

If you just want to know the Watt Hours of insolation you received, you can use another extended variable and calculate the “energy” of the variable you’re using for insolation as I do in v8 and v9 below.

image

1 Like
#6

Thanks - changed user account to my donor account (accidentally had two accounts). Yes calculating efficiency would be fantastic and I have all that data available. I will look at your post and see if I can replicate it. I am particularly interested in efficiency changes across seasons and long term changes.

#7

Just graphing watt hours received over time would be a simple start because I could rig up a simple calculation to track changes over time, until I can implement the more accurate “actual” efficiency measure from lwsmiser.