Solar scene: single battery chip, reworked chip cluster

- Merge the battery power and SoC chips into one: the SoC drives the
  battery level icon (like the energy distribution card), the value is
  the battery power, and the chip colour shows charge vs discharge.
- Battery flows: no battery -> home line while charging; bead from PV
  or grid (whichever feeds the charge) into the battery; static home
  link when idle.
- Chip cluster: the home chip sits over the house, grid and battery
  flank it halfway up to the PV chip.
- Drop the low-carbon chip and its now-unused plumbing.
- Add the card without a default title in the Now view strategy.

src/panels/energy/strategies/energy-cards.ts

@@ -4,6 +4,7 @@ import type {
   GridSourceTypeEnergyPreference,
 } from "../../../data/energy";
 import type { LovelaceStrategyConfig } from "../../../data/lovelace/config/strategy";
+import type { HomeAssistant } from "../../../types";
 
 /** Strategy config shared by the per-view energy strategies. */
 export interface EnergyViewStrategyConfig extends LovelaceStrategyConfig {
@@ -36,6 +37,22 @@ export const hasReturn = (prefs: EnergyPreferences): boolean =>
 export const hasSolar = (prefs: EnergyPreferences): boolean =>
   prefs.energy_sources.some((source) => source.type === "solar");
 
+/** Solar source with a live power sensor (`stat_rate`); the "now" scene card shows live power only. */
+export const hasSolarPower = (prefs: EnergyPreferences): boolean =>
+  prefs.energy_sources.some(
+    (source) => source.type === "solar" && !!source.stat_rate
+  );
+
+/** A home location is configured when both coordinates are finite and not the meaningless (0, 0) origin. */
+export const hasLocation = (hass: HomeAssistant): boolean => {
+  const { latitude, longitude } = hass.config;
+  return (
+    Number.isFinite(latitude) &&
+    Number.isFinite(longitude) &&
+    !(latitude === 0 && longitude === 0)
+  );
+};
+
 export const hasBattery = (prefs: EnergyPreferences): boolean =>
   prefs.energy_sources.some((source) => source.type === "battery");
 
@@ -262,6 +279,12 @@ export const ENERGY_CARD_CATALOG: readonly EnergyCardCatalogEntry[] = [
   ),
 
   // --- Now (power) ---
+  entry(
+    "now",
+    "energy-solar-scene-now",
+    "ui.panel.energy.cards.energy_solar_scene_title",
+    (p) => hasSolarPower(p)
+  ),
   entry(
     "now",
     "power-sources-graph",

src/panels/energy/strategies/power-view-strategy.ts

@@ -9,6 +9,7 @@ import type { HomeAssistant } from "../../../types";
 import type { EnergyViewStrategyConfig } from "./energy-cards";
 import {
   hasGasRateSource,
+  hasLocation,
   hasPowerDevices,
   hasPowerSources,
   hasWaterRateDevices,
@@ -71,6 +72,21 @@ export class PowerViewStrategy extends ReactiveElement {
       return view;
     }
 
+    // Solar scene (snapshot): a live, present-instant 3D view, pinned to the top of the Now tab. Needs a home
+    // location to place the house, so it is skipped entirely when none is configured.
+    if (
+      hasLocation(hass) &&
+      isEnergyCardVisible("now", "energy-solar-scene-now", prefs, hidden)
+    ) {
+      chartsSection.cards!.push({
+        type: "energy-solar-scene-now",
+        collection_key: collectionKey,
+        grid_options: {
+          columns: 36,
+        },
+      });
+    }
+
     if (hasPowerSrc) {
       badges.push({
         type: "power-total",

src/panels/lovelace/create-element/create-card-element.ts

@@ -50,6 +50,8 @@ const LAZY_LOAD_TYPES = {
     import("../cards/energy/hui-energy-devices-detail-graph-card"),
   "energy-distribution": () =>
     import("../cards/energy/hui-energy-distribution-card"),
+  "energy-solar-scene-now": () =>
+    import("../cards/energy/hui-energy-solar-scene-now-card"),
   "energy-gas-graph": () => import("../cards/energy/hui-energy-gas-graph-card"),
   "energy-water-graph": () =>
     import("../cards/energy/hui-energy-water-graph-card"),

src/translations/en.json

@@ -11297,6 +11297,16 @@
           "energy_gas_graph_title": "Gas consumption",
           "energy_water_graph_title": "Water consumption",
           "energy_distribution_title": "Energy distribution",
+          "energy_solar_scene_title": "Solar scene",
+          "energy_solar_scene_a11y": {
+            "solar": "solar production {value}",
+            "home": "home consumption {value}",
+            "grid_import": "grid import {value}",
+            "grid_export": "grid export {value}",
+            "battery_charge": "battery charging {value}",
+            "battery_discharge": "battery discharging {value}",
+            "battery_soc": "battery charge {value}"
+          },
           "energy_sources_table_title": "Sources",
           "energy_devices_graph_title": "Individual devices total usage",
           "energy_devices_detail_graph_title": "Individual devices detail usage",

test/panels/energy/strategies/energy-cards.test.ts

@@ -3,12 +3,15 @@ import type {
   EnergyPreferences,
   EnergySource,
 } from "../../../../src/data/energy";
+import type { HomeAssistant } from "../../../../src/types";
 import {
   applicableEnergyCardKeys,
   ENERGY_CARD_CATALOG,
   energyCardKey,
   hasEnergySource,
   hasGasRateSource,
+  hasLocation,
+  hasSolarPower,
   hasWaterRateSource,
   isEnergyCardHidden,
   isEnergyCardVisible,
@@ -225,3 +228,42 @@ describe("isEnergyCardVisible", () => {
     }
   });
 });
+
+describe("hasSolarPower", () => {
+  const SOLAR_RATE = source({
+    type: "solar",
+    stat_energy_from: "sensor.solar",
+    stat_rate: "sensor.solar_power",
+  });
+
+  it("requires a solar source with a live rate sensor", () => {
+    expect(hasSolarPower(makePrefs({ energy_sources: [SOLAR_RATE] }))).toBe(
+      true
+    );
+    // Solar configured for energy only (no stat_rate) -> nothing live for the "now" card.
+    expect(hasSolarPower(makePrefs({ energy_sources: [SOLAR] }))).toBe(false);
+    // No solar source at all.
+    expect(hasSolarPower(makePrefs({ energy_sources: [GRID_RETURN] }))).toBe(
+      false
+    );
+  });
+});
+
+describe("hasLocation", () => {
+  const hassAt = (latitude: number, longitude: number): HomeAssistant =>
+    ({ config: { latitude, longitude } }) as unknown as HomeAssistant;
+
+  it("is true for real coordinates, including negative ones", () => {
+    expect(hasLocation(hassAt(52.37, 4.9))).toBe(true);
+    expect(hasLocation(hassAt(-33.87, -70.66))).toBe(true);
+  });
+
+  it("is false at the meaningless (0, 0) origin", () => {
+    expect(hasLocation(hassAt(0, 0))).toBe(false);
+  });
+
+  it("is false when a coordinate is not finite", () => {
+    expect(hasLocation(hassAt(NaN, 4.9))).toBe(false);
+    expect(hasLocation(hassAt(52.37, Infinity))).toBe(false);
+  });
+});