diff --git a/custom_components/xiaomi_miot/core/device.py b/custom_components/xiaomi_miot/core/device.py
index 15f1fe039..2d20f1b4a 100644
--- a/custom_components/xiaomi_miot/core/device.py
+++ b/custom_components/xiaomi_miot/core/device.py
@@ -38,6 +38,8 @@
     get_value,
     DeviceException,
     is_offline_exception,
+    normalize_power_cost_value,
+    power_cost_period,
     update_attrs_with_suffix,
 )
 from .templates import template
@@ -1214,6 +1216,7 @@ async def update_cloud_statistics(self, commands=None):
                 attrs[anm] = rls
             elif isinstance(rls, dict):
                 update_attrs_with_suffix(attrs, rls)
+        attrs = self._filter_power_cost_statistics(attrs, dt.now())
         if attrs:
             self.available = True
             self.props.update(attrs)
@@ -1221,6 +1224,37 @@ async def update_cloud_statistics(self, commands=None):
             self.dispatch(self.decode_attrs(attrs))
         return attrs
 
+    def _filter_power_cost_statistics(self, attrs, now):
+        """Filter invalid and decreasing power cost statistics."""
+        result = dict(attrs)
+        periods = self.data.setdefault('_power_cost_periods', {})
+        for key in list(result):
+            period = power_cost_period(key, now)
+            if not period:
+                continue
+            value = normalize_power_cost_value(result[key])
+            if value is None:
+                result.pop(key)
+                continue
+            previous = normalize_power_cost_value(self.props.get(key))
+            if (
+                periods.get(key) == period
+                and previous is not None
+                and value < previous
+            ):
+                self.log.warning(
+                    'Ignore decreasing power cost in the same period: '
+                    '%s: %s -> %s, period=%s',
+                    key,
+                    previous,
+                    value,
+                    period,
+                )
+                result.pop(key)
+                continue
+            periods[key] = period
+        return result
+
     @cached_property
     def miio_cloud_records(self):
         return self.custom_config_list('miio_cloud_records') or []
diff --git a/custom_components/xiaomi_miot/core/templates.py b/custom_components/xiaomi_miot/core/templates.py
index ab3dfa8ed..5557f596b 100644
--- a/custom_components/xiaomi_miot/core/templates.py
+++ b/custom_components/xiaomi_miot/core/templates.py
@@ -104,7 +104,7 @@
                                   "'target_temperature': state[6:8] | int(0,16),"
                                   "'load_power': results[2] | default(0) | float | round(2),"
                                   "} }}",
-    'micloud_statistics_power_cost': "{%- set dat = namespace(today=0,month=0) %}"
+    'micloud_statistics_power_cost': "{%- set dat = namespace(today=none,month=none) %}"
                                      "{%- set tim = now() %}"
                                      "{%- set stm = tim - timedelta(minutes=tim.minute,seconds=tim.second) %}"
                                      "{%- set tod = stm - timedelta(hours=tim.hour) %}"
@@ -114,17 +114,19 @@
                                      "{%- for d in (result or []) %}"
                                      "{%-   set t = d.time | default(0) | int(0) %}"
                                      "{%-   if t >= stm %}"
-                                     "{%-     set v = (d.value | default('[]') | string | from_json) or [] %}"
-                                     "{%-     set n = v[0] | default(0) %}"
-                                     "{%-     if t >= tod %}"
-                                     "{%-       set dat.today = n %}"
+                                     "{%-     set v = (d.value | default('[]', true) | string | from_json) or [] %}"
+                                     "{%-     set n = v[0] | default(none) %}"
+                                     "{%-     if n is number and n is not boolean and n >= 0 %}"
+                                     "{%-       if t >= tod %}"
+                                     "{%-         set dat.today = n %}"
+                                     "{%-       endif %}"
+                                     "{%-       set dat.month = (dat.month or 0) + n %}"
                                      "{%-     endif %}"
-                                     "{%-     set dat.month = dat.month + n %}"
                                      "{%-   endif %}"
                                      "{%- endfor %}"
                                      "{{ {"
-                                     "'power_cost_today': dat.today | round(3),"
-                                     "'power_cost_month': dat.month | round(3),"
+                                     "'power_cost_today': dat.today | round(3) if dat.today is number else none,"
+                                     "'power_cost_month': dat.month | round(3) if dat.month is number else none,"
                                      "} }}",
     'midr_rv_mirror_cloud_props': "{%- set sta = props.get('prop.Status',0) | int %}"
                                   "{%- set pos = props.get('prop.Position','{}') | from_json %}"
diff --git a/custom_components/xiaomi_miot/core/utils.py b/custom_components/xiaomi_miot/core/utils.py
index d7bff47ba..73a6574a4 100644
--- a/custom_components/xiaomi_miot/core/utils.py
+++ b/custom_components/xiaomi_miot/core/utils.py
@@ -1,6 +1,7 @@
 import os
 import re
 import json
+import math
 import locale
 import aiohttp
 import asyncio
@@ -8,6 +9,7 @@
 import logging
 import fnmatch
 import voluptuous as vol
+from datetime import datetime
 from typing import Type, Tuple, Optional, Callable, Set
 from functools import wraps
 from homeassistant.core import HomeAssistant, split_entity_id  # noqa
@@ -20,6 +22,30 @@
 from .const import DOMAIN, DEVICE_CUSTOMIZES, DATA_CUSTOMIZE
 from .translation_languages import TRANSLATION_LANGUAGES
 
+POWER_COST_PATTERN = re.compile(
+    r'(?:^|\.)(power_cost_(today|month)(?:_\d+)?)$'
+)
+
+
+def power_cost_period(attribute: str, timestamp: datetime) -> str | None:
+    """Return the local reset period for a power cost attribute."""
+    if match := POWER_COST_PATTERN.search(attribute):
+        return timestamp.strftime(
+            '%Y-%m-%d' if match.group(2) == 'today' else '%Y-%m'
+        )
+    return None
+
+
+def normalize_power_cost_value(value) -> float | None:
+    """Return a finite non-negative power cost value."""
+    if isinstance(value, bool):
+        return None
+    try:
+        value = float(value)
+    except (TypeError, ValueError):
+        return None
+    return value if math.isfinite(value) and value >= 0 else None
+
 
 def get_value(obj, key, def_value=None, sep='.'):
     keys = f'{key}'.split(sep)
diff --git a/custom_components/xiaomi_miot/sensor.py b/custom_components/xiaomi_miot/sensor.py
index 3faed42f3..197b746ca 100644
--- a/custom_components/xiaomi_miot/sensor.py
+++ b/custom_components/xiaomi_miot/sensor.py
@@ -13,6 +13,8 @@
     SensorDeviceClass,
     SensorStateClass,
 )
+from homeassistant.core import callback
+from homeassistant.helpers.event import async_track_time_change
 from homeassistant.helpers.restore_state import RestoreEntity, RestoredExtraData
 from homeassistant.helpers.update_coordinator import DataUpdateCoordinator
 
@@ -33,7 +35,13 @@
     MiotSpec,
     MiotService,
 )
-from .core.utils import local_zone, get_translation
+from .core.utils import (
+    POWER_COST_PATTERN,
+    get_translation,
+    local_zone,
+    normalize_power_cost_value,
+    power_cost_period,
+)
 
 _LOGGER = logging.getLogger(__name__)
 DATA_KEY = f'{ENTITY_DOMAIN}.{DOMAIN}'
@@ -130,6 +138,47 @@ def on_init(self):
     def get_state(self) -> dict:
         return {self.attr: self._attr_native_value}
 
+    async def async_added_to_hass(self):
+        await super().async_added_to_hass()
+        if not POWER_COST_PATTERN.search(self.attr):
+            return
+        now = datetime.now(local_zone(self.hass))
+        current_period = power_cost_period(self.attr, now)
+        self._power_cost_period = current_period
+        restored = await self.async_get_last_state()
+        if restored:
+            restored_value = normalize_power_cost_value(restored.state)
+            restored_at = restored.last_changed.astimezone(
+                local_zone(self.hass)
+            )
+            restored_period = power_cost_period(
+                self.attr,
+                restored_at,
+            )
+            if restored_value is None or restored_period != current_period:
+                self._attr_native_value = None
+            else:
+                self._attr_native_value = restored_value
+        self.async_on_remove(
+            async_track_time_change(
+                self.hass,
+                self._reset_power_cost_period,
+                hour=0,
+                minute=0,
+                second=0,
+            )
+        )
+
+    @callback
+    def _reset_power_cost_period(self, now: datetime):
+        """Reset accumulated power at an observed local period boundary."""
+        period = power_cost_period(self.attr, now)
+        if not period or period == self._power_cost_period:
+            return
+        self._power_cost_period = period
+        self._attr_native_value = 0
+        self.async_write_ha_state()
+
     def set_state(self, data: dict):
         value = self.conv.value_from_dict(data)
         prop = self._miot_property
@@ -144,8 +193,33 @@ def set_state(self, data: dict):
                     value = round(float(value), 3)
             except (TypeError, ValueError):
                 value = None
+            period = power_cost_period(
+                self.attr,
+                datetime.now(local_zone(self.hass)),
+            )
+            if period:
+                value = normalize_power_cost_value(value)
+                if value is None:
+                    return
             if self.device_class == SensorDeviceClass.TIMESTAMP:
                 value = datetime_with_tzinfo(value)
+            previous = getattr(self, '_attr_native_value', None)
+            if (
+                period
+                and getattr(self, '_power_cost_period', None) == period
+                and previous is not None
+                and value < previous
+            ):
+                self.log.warning(
+                    'Ignore decreasing power cost in the same period: '
+                    '%s: %s -> %s',
+                    self.attr,
+                    previous,
+                    value,
+                )
+                return
+            if period:
+                self._power_cost_period = period
             self._attr_native_value = value
 
     @cached_property