How to run a scheduled event at Solar Noon?

[sgraystar]

With solar panels installed there is an advantage to schedule events when solar generation is likely at a maximimum.

There are advanced approaches using solar forecasts, but a simple approach is to use a scheduler event to run at SolarNoon +/- offset, similar to current run at Sunrise +/- offset.

I realise this can be done wholly by scripting but would prefer to retain the ability to use the scheduler gui.

If an event is configured to run at Sunrise +/- offset via the GUI, is it possible to script an replacement of the start time with some other value such as a simplified solarNoon = (sunrise + sunset)/2?

Any ideas?

This is a little clumsy, but using event name is one way of adding solarNoon by the existing gui.
What would be the equivalent of ' io.writefile('/tmp/lm-scheduler-clear', '')' for the clipsal/schneider firmware?

Code:

local name = 'solarNoon%'
local maxOffsetHours = 6    -- avoid 24hr boundaries

for _, evt in ipairs(db:getall('SELECT * FROM scheduler_events WHERE name LIKE ?', name)) do
  if evt then 
    local _, _, plusMinus, offsetHour, offsetMin = string.find(evt.name, "^solarNoon%s*([+-])%s*(0[0-"..maxOffsetHours.."])([0-5]%d)%D*")

    if plusMinus and offsetHour and offsetMin and evt.type == '' then
      local sunrise, sunset = rscalc(latitudeMel, longitudeMel)
      local solarNoon = math.floor(((sunset + sunrise) / 2) + 0.5)

      local offsetMinutes = (offsetHour * 60) + offsetMin
      local eventMinutes
      if plusMinus == '+' then
        eventMinutes = solarNoon + offsetMinutes
      else
        eventMinutes = solarNoon - offsetMinutes
      end

      local eventStartHour = math.floor(eventMinutes / 60)
      local eventStartMin = math.floor(eventMinutes % 60)
     
      db:update('scheduler_events', {
        start_hour = eventStartHour,
        start_min = eventStartMin
      }, { id = evt.id })
     
      -- io.writefile('/tmp/lm-scheduler-clear', '')

    else
      log("Error. '"..evt.name.."' event name must begin with 'solarNoon[+-]HHMM ...' where max HH = 0"..maxOffsetHours..", and event setting 'Run at:' = 'Specific time'")
    end
  end
end