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Hi, Here is a stripped down LUA port of the SunCalc JavaScript library by Vladimir Agafonkin (@mourner) https://github.com/mourner/suncalc I've done some minor modifications to the code, mainly due to the fact that the original functions returned the result in radians. Also, the result was negative or positive relative to the South direction, so I converted it to heading in degrees: 0 - North, 90 - East, 180 - South, 270 - West. I've ported just the azimuth and elevation computation (for now). The scene updates 2 simple global variables (must be created first, names can be changed), and based on these variables, scenes can be triggered, or a VD can display the data. Tested by entering Vladimir's data (see test.js) and by knowing that today at 13:26 was solar noon at my location (180° azimuth at that time - see attached picture). I use this scene to drive my sunshades through the day when is hot outside --[[ %% autostart %% properties %% events %% globals --]] --[[ Scene for computing solar azimuth and elevation, based on SunCalc project https://github.com/mourner/suncalc Copyright (c) 2014, Vladimir Agafonkin All rights reserved. --]] local refreshRate = 60 -- update rate in seconds local azimuthVar = 'solarAzimuth' local elevationVar = 'solarElevation' local debug = true local locationInfo = api.get('/settings/location') print('Location: ' .. locationInfo.city) print('Latitude: ' .. locationInfo.latitude) print('Longitude: ' .. locationInfo.longitude) print() local PI = math.pi local sin = math.sin local cos = math.cos local tan = math.tan local asin = math.asin local atan = math.atan2 local acos = math.acos local rad = PI / 180 local dayMs = 1000 * 60 * 60 * 24 local J1970 = 2440588 local J2000 = 2451545 local e = rad * 23.4397 -- obliquity of the Earth function toJulian(timestamp) return timestamp / dayMs - 0.5 + J1970 end function fromJulian(j) return (j + 0.5 - J1970) * dayMs end function toDays(timestamp) return toJulian(timestamp) - J2000 end function rightAscension(l, b) return atan(sin(l) * cos(e) - tan(b) * sin(e), cos(l)) end function declination(l, b) return asin(sin(b) * cos(e) + cos(b) * sin(e) * sin(l)) end function azimuth(H, phi, dec) return atan(sin(H), cos(H) * sin(phi) - tan(dec) * cos(phi)) end function elevation(H, phi, dec) return asin(sin(phi) * sin(dec) + cos(phi) * cos(dec) * cos(H)) end function siderealTime(d, lw) return rad * (280.16 + 360.9856235 * d) - lw end function solarMeanAnomaly(d) return rad * (357.5291 + 0.98560028 * d) end function eclipticLongitude(M) local C = rad * (1.9148 * sin(M) + 0.02 * sin(2 * M) + 0.0003 * sin(3 * M)) -- equation of center local P = rad * 102.9372 -- perihelion of the Earth return M + C + P + PI end function sunCoords(d) local M = solarMeanAnomaly(d) local L = eclipticLongitude(M) return { dec = declination(L, 0), ra = rightAscension(L, 0) } end local SunCalc = {} SunCalc.getPosition = function (timestamp, lat, lng) local lw = rad * -lng local phi = rad * lat local d = toDays(timestamp) local c = sunCoords(d) local H = siderealTime(d, lw) - c.ra return { azimuth = azimuth(H, phi, c.dec) * 180 / PI, elevation = elevation(H, phi, c.dec) * 180 / PI } end local pos = {} while true do pos = SunCalc.getPosition(os.time() * 1000, locationInfo.latitude, locationInfo.longitude) fibaro:setGlobal(azimuthVar, string.format('%.2f', pos.azimuth + 180)) fibaro:setGlobal(elevationVar, string.format('%.2f', pos.elevation)) if (debug) then print('Azimuth: ' .. string.format('%.2f', pos.azimuth + 180) .. '°') print('Elevation: ' .. string.format('%.2f', pos.elevation) .. '°') end fibaro:sleep(refreshRate * 1000) end