From 8ab2a78e684e1c4f088c0f7cd6fcd06f76943892 Mon Sep 17 00:00:00 2001
From: andig <andi@evcc.io>
Date: Mon, 10 Mar 2025 11:08:36 +0100
Subject: [PATCH] Solar forecast: reset inconsistent metrics (#19605)

---
 core/site.go         | 22 ++++++++++++++++++----
 core/site_tariffs.go |  4 ++--
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/core/site.go b/core/site.go
index 5149d0b20..04f0ce293 100644
--- a/core/site.go
+++ b/core/site.go
@@ -323,14 +323,28 @@ func (site *Site) restoreSettings() error {
 	fcstEnergy, err := settings.Float(keys.SolarAccForecast)
 
 	if err == nil && settings.Json(keys.SolarAccYield, &pvEnergy) == nil {
-		site.fcstEnergy.Accumulated = fcstEnergy
-
+		var nok bool
 		for _, name := range site.Meters.PVMetersRef {
 			if fcst, ok := pvEnergy[name]; ok {
 				site.pvEnergy[name].Accumulated = fcst
 			} else {
-				// TODO decide auto-reset?
-				site.log.WARN.Printf("cannot restore accumulated solar yield for: %s (may need to reset solar statistics)", name)
+				nok = true
+				site.log.WARN.Printf("accumulated solar yield: cannot restore %s", name)
+			}
+		}
+
+		if !nok {
+			site.fcstEnergy.Accumulated = fcstEnergy
+			site.log.DEBUG.Printf("accumulated solar yield: restored %.3fkWh forecasted, %+v produced", fcstEnergy, pvEnergy)
+		} else {
+			// reset metrics
+			site.log.WARN.Printf("accumulated solar yield: metrics reset")
+
+			settings.Delete(keys.SolarAccForecast)
+			settings.Delete(keys.SolarAccYield)
+
+			for _, pe := range site.pvEnergy {
+				pe.Accumulated = 0
 			}
 		}
 	}
diff --git a/core/site_tariffs.go b/core/site_tariffs.go
index 6b58d6d58..bd5d8dae7 100644
--- a/core/site_tariffs.go
+++ b/core/site_tariffs.go
@@ -157,8 +157,8 @@ func (site *Site) solarDetails(solar timeseries) solarDetails {
 		scale := produced / fcst
 		site.log.DEBUG.Printf("solar forecast: accumulated %.3fkWh, produced %.3fkWh, scale %.3f", fcst, produced, scale)
 
-		const minEnergy = 0.1
-		if produced > minEnergy && fcst > minEnergy { /*kWh*/
+		const minEnergy = 0.5 // kWh
+		if produced+fcst > minEnergy {
 			res.Scale = lo.ToPtr(scale)
 		}
 	}