From c1067111e4870212e47db772360378987d015dde Mon Sep 17 00:00:00 2001
From: Johannes Rudolph <jrudolph@meshcloud.io>
Date: Sun, 23 Aug 2026 13:10:24 +0200
Subject: [PATCH] Loadpoint: don't reserve surplus when paused by feed-in
 priority (#33072)

---
 core/loadpoint.go            |  4 +-
 core/site_prioritize_test.go | 81 ++++++++++++++++++++++++++++++++++++
 2 files changed, 84 insertions(+), 1 deletion(-)

diff --git a/core/loadpoint.go b/core/loadpoint.go
index 6b6b23f3b..db2a1daed 100644
--- a/core/loadpoint.go
+++ b/core/loadpoint.go
@@ -1047,7 +1047,9 @@ func (lp *Loadpoint) charging() bool {
 func (lp *Loadpoint) PvChargeStarting() bool {
 	lp.RLock()
 	enabled := lp.enabled
-	pvTimerRunning := !lp.pvTimer.IsZero()
+	// an elapsed timer means a delay was skipped, e.g. by a feed-in pause, not an
+	// enable pending, hence such a loadpoint claims no surplus
+	pvTimerRunning := !lp.pvTimer.IsZero() && !lp.pvTimer.Equal(elapsed)
 	lp.RUnlock()
 
 	if lp.GetMode() != api.ModePV || !lp.connected() || lp.chargeGoalReached(enabled) {
diff --git a/core/site_prioritize_test.go b/core/site_prioritize_test.go
index aeaae88b8..f3fa115cd 100644
--- a/core/site_prioritize_test.go
+++ b/core/site_prioritize_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 	"time"
 
+	evbus "github.com/asaskevich/EventBus"
 	"github.com/benbjohnson/clock"
 	"github.com/evcc-io/evcc/api"
 	"github.com/evcc-io/evcc/core/loadpoint"
@@ -44,6 +45,8 @@ func TestPvChargeStarting(t *testing.T) {
 		{"disconnected", newPVLoadpoint(0, api.ModePV, api.StatusA, false, now), false},
 		{"not pv mode", newPVLoadpoint(0, api.ModeNow, api.StatusB, false, now), false},
 		{"enable pending but car full", enablePendingFull, false},
+		// elapsed means a delay was skipped, e.g. by a feed-in pause, not an enable pending
+		{"timer elapsed", newPVLoadpoint(0, api.ModePV, api.StatusB, false, elapsed), false},
 	}
 
 	for _, tc := range tc {
@@ -91,4 +94,82 @@ func TestReservedPVPower(t *testing.T) {
 	}
 }
 
+// feedInCharger is a stateful charger, unlike the mocks used elsewhere, since the
+// feed-in pause is asserted across multiple update cycles
+type feedInCharger struct {
+	status  api.ChargeStatus
+	enabled bool
+}
+
+func (c *feedInCharger) Status() (api.ChargeStatus, error) { return c.status, nil }
+func (c *feedInCharger) Enabled() (bool, error)            { return c.enabled, nil }
+func (c *feedInCharger) MaxCurrent(int64) error            { return nil }
+
+func (c *feedInCharger) Enable(v bool) error {
+	c.enabled = v
+	// a disabled charger stops drawing, i.e. reports connected instead of charging
+	if !v && c.status == api.StatusC {
+		c.status = api.StatusB
+	}
+	return nil
+}
+
+// TestReservedPVPowerSmartFeedInPause asserts that a loadpoint paused by its smart feed-in
+// priority limit does not reserve surplus: it is meant to export instead of charge
+func TestReservedPVPowerSmartFeedInPause(t *testing.T) {
+	// the feed-in rate rises above the limit while the loadpoint is idle or charging
+	for _, tc := range []struct {
+		name    string
+		status  api.ChargeStatus
+		enabled bool
+	}{
+		{"idle", api.StatusB, false},
+		{"charging", api.StatusC, true},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			clck := clock.NewMock()
+			limit := 0.05
+
+			car := newPVLoadpoint(1, api.ModePV, tc.status, tc.enabled, time.Time{})
+			car.bus = evbus.New()
+			car.clock = clck
+			car.charger = &feedInCharger{status: tc.status, enabled: tc.enabled}
+			car.chargeMeter = &Null{} // silence nil panics
+			car.chargeRater = &Null{} // silence nil panics
+			car.chargeTimer = &Null{} // silence nil panics
+			car.wakeUpTimer = NewTimer()
+			car.smartFeedInPriorityLimit = &limit
+			car.vehicleSoc = 20
+			car.limitSoc = 80
+			attachListeners(t, car)
+
+			low := newPVLoadpoint(0, api.ModePV, api.StatusB, false, time.Time{})
+
+			site := &Site{
+				log:        util.NewLogger("site"),
+				loadpoints: []*Loadpoint{car, low},
+			}
+
+			// checkSmartLimit looks up rates by wall clock time, not lp.clock
+			now := time.Now()
+			feedin := api.Rates{{Start: now.Add(-time.Hour), End: now.Add(time.Hour), Value: limit + 0.01}}
+
+			// the pause holds across cycles, so must the absence of a reservation
+			for i := range 2 {
+				car.Update(-3500, 0, nil, feedin, false, false, 0, nil, nil, nil)
+
+				if car.enabled {
+					t.Fatalf("cycle %d: car must be paused by the feed-in limit", i)
+				}
+
+				if got := site.reservedPVPower(low); got != 0 {
+					t.Errorf("cycle %d: paused car reserves %.0fW, want 0W (pvTimer %v)", i, got, car.pvTimer)
+				}
+
+				clck.Add(time.Minute)
+			}
+		})
+	}
+}
+
 var _ loadpoint.API = (*Loadpoint)(nil)