diff --git a/homeassistant/components/sensor/bitcoin.py b/homeassistant/components/sensor/bitcoin.py
index ca921f4fca7..dc11f7038c2 100644
--- a/homeassistant/components/sensor/bitcoin.py
+++ b/homeassistant/components/sensor/bitcoin.py
@@ -17,24 +17,24 @@ REQUIREMENTS = ['blockchain==1.1.2']
 _LOGGER = logging.getLogger(__name__)
 OPTION_TYPES = {
     'wallet': ['Wallet balance', 'BTC'],
-    'exchangerate': ['Exchange rate (1 BTC)', ''],
+    'exchangerate': ['Exchange rate (1 BTC)', None],
     'trade_volume_btc': ['Trade volume', 'BTC'],
     'miners_revenue_usd': ['Miners revenue', 'USD'],
     'btc_mined': ['Mined', 'BTC'],
     'trade_volume_usd': ['Trade volume', 'USD'],
-    'difficulty': ['Difficulty', ''],
+    'difficulty': ['Difficulty', None],
     'minutes_between_blocks': ['Time between Blocks', 'min'],
-    'number_of_transactions': ['No. of Transactions', ''],
+    'number_of_transactions': ['No. of Transactions', None],
     'hash_rate': ['Hash rate', 'PH/s'],
-    'timestamp': ['Timestamp', ''],
-    'mined_blocks': ['Minded Blocks', ''],
-    'blocks_size': ['Block size', ''],
+    'timestamp': ['Timestamp', None],
+    'mined_blocks': ['Minded Blocks', None],
+    'blocks_size': ['Block size', None],
     'total_fees_btc': ['Total fees', 'BTC'],
     'total_btc_sent': ['Total sent', 'BTC'],
     'estimated_btc_sent': ['Estimated sent', 'BTC'],
     'total_btc': ['Total', 'BTC'],
-    'total_blocks': ['Total Blocks', ''],
-    'next_retarget': ['Next retarget', ''],
+    'total_blocks': ['Total Blocks', None],
+    'next_retarget': ['Next retarget', None],
     'estimated_transaction_volume_usd': ['Est. Transaction volume', 'USD'],
     'miners_revenue_btc': ['Miners revenue', 'BTC'],
     'market_price_usd': ['Market price', 'USD']
diff --git a/homeassistant/components/sensor/dht.py b/homeassistant/components/sensor/dht.py
index 0e39ef7382f..4f11ba7734f 100644
--- a/homeassistant/components/sensor/dht.py
+++ b/homeassistant/components/sensor/dht.py
@@ -20,7 +20,7 @@ REQUIREMENTS = ['http://github.com/mala-zaba/Adafruit_Python_DHT/archive/'
 
 _LOGGER = logging.getLogger(__name__)
 SENSOR_TYPES = {
-    'temperature': ['Temperature', ''],
+    'temperature': ['Temperature', None],
     'humidity': ['Humidity', '%']
 }
 # Return cached results if last scan was less then this time ago
diff --git a/homeassistant/components/sensor/ecobee.py b/homeassistant/components/sensor/ecobee.py
index 02a2575d88b..91892f63617 100644
--- a/homeassistant/components/sensor/ecobee.py
+++ b/homeassistant/components/sensor/ecobee.py
@@ -36,7 +36,7 @@ DEPENDENCIES = ['ecobee']
 SENSOR_TYPES = {
     'temperature': ['Temperature', TEMP_FAHRENHEIT],
     'humidity': ['Humidity', '%'],
-    'occupancy': ['Occupancy', '']
+    'occupancy': ['Occupancy', None]
 }
 
 _LOGGER = logging.getLogger(__name__)
diff --git a/homeassistant/components/sensor/efergy.py b/homeassistant/components/sensor/efergy.py
index 447903a714e..8eba0149408 100644
--- a/homeassistant/components/sensor/efergy.py
+++ b/homeassistant/components/sensor/efergy.py
@@ -16,8 +16,8 @@ _LOGGER = logging.getLogger(__name__)
 _RESOURCE = 'https://engage.efergy.com/mobile_proxy/'
 SENSOR_TYPES = {
     'instant_readings': ['Energy Usage', 'kW'],
-    'budget': ['Energy Budget', ''],
-    'cost': ['Energy Cost', ''],
+    'budget': ['Energy Budget', None],
+    'cost': ['Energy Cost', None],
 }
 
 
diff --git a/homeassistant/components/sensor/forecast.py b/homeassistant/components/sensor/forecast.py
index 42fbe26b9cf..8cbc332678e 100644
--- a/homeassistant/components/sensor/forecast.py
+++ b/homeassistant/components/sensor/forecast.py
@@ -19,13 +19,13 @@ _LOGGER = logging.getLogger(__name__)
 # Sensor types are defined like so:
 # Name, si unit, us unit, ca unit, uk unit, uk2 unit
 SENSOR_TYPES = {
-    'summary': ['Summary', '', '', '', '', ''],
-    'icon': ['Icon', '', '', '', '', ''],
+    'summary': ['Summary', None, None, None, None, None],
+    'icon': ['Icon', None, None, None, None, None],
     'nearest_storm_distance': ['Nearest Storm Distance',
                                'km', 'm', 'km', 'km', 'm'],
     'nearest_storm_bearing': ['Nearest Storm Bearing',
                               '°', '°', '°', '°', '°'],
-    'precip_type': ['Precip', '', '', '', '', ''],
+    'precip_type': ['Precip', None, None, None, None, None],
     'precip_intensity': ['Precip Intensity', 'mm', 'in', 'mm', 'mm', 'mm'],
     'precip_probability': ['Precip Probability', '%', '%', '%', '%', '%'],
     'temperature': ['Temperature', '°C', '°F', '°C', '°C', '°C'],
diff --git a/homeassistant/components/sensor/glances.py b/homeassistant/components/sensor/glances.py
index c2bd96c8eea..eb38e3df265 100644
--- a/homeassistant/components/sensor/glances.py
+++ b/homeassistant/components/sensor/glances.py
@@ -31,11 +31,11 @@ SENSOR_TYPES = {
     'swap_use_percent': ['Swap Use', '%'],
     'swap_use': ['Swap Use', 'GiB'],
     'swap_free': ['Swap Free', 'GiB'],
-    'processor_load': ['CPU Load', ''],
-    'process_running': ['Running', ''],
-    'process_total': ['Total', ''],
-    'process_thread': ['Thread', ''],
-    'process_sleeping': ['Sleeping', '']
+    'processor_load': ['CPU Load', None],
+    'process_running': ['Running', None],
+    'process_total': ['Total', None],
+    'process_thread': ['Thread', None],
+    'process_sleeping': ['Sleeping', None]
 }
 
 _LOGGER = logging.getLogger(__name__)
diff --git a/homeassistant/components/sensor/openweathermap.py b/homeassistant/components/sensor/openweathermap.py
index 84784a19546..a5509904264 100644
--- a/homeassistant/components/sensor/openweathermap.py
+++ b/homeassistant/components/sensor/openweathermap.py
@@ -16,8 +16,8 @@ from homeassistant.helpers.entity import Entity
 REQUIREMENTS = ['pyowm==2.3.0']
 _LOGGER = logging.getLogger(__name__)
 SENSOR_TYPES = {
-    'weather': ['Condition', ''],
-    'temperature': ['Temperature', ''],
+    'weather': ['Condition', None],
+    'temperature': ['Temperature', None],
     'wind_speed': ['Wind speed', 'm/s'],
     'humidity': ['Humidity', '%'],
     'pressure': ['Pressure', 'mbar'],
@@ -71,7 +71,7 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
         pass
 
     if forecast == 1:
-        SENSOR_TYPES['forecast'] = ['Forecast', '']
+        SENSOR_TYPES['forecast'] = ['Forecast', None]
         dev.append(OpenWeatherMapSensor(data, 'forecast', unit))
 
     add_devices(dev)
diff --git a/homeassistant/components/sensor/sabnzbd.py b/homeassistant/components/sensor/sabnzbd.py
index 98d76a302dd..6b42453b5d3 100644
--- a/homeassistant/components/sensor/sabnzbd.py
+++ b/homeassistant/components/sensor/sabnzbd.py
@@ -17,7 +17,7 @@ REQUIREMENTS = ['https://github.com/jamespcole/home-assistant-nzb-clients/'
                 '#python-sabnzbd==0.1']
 
 SENSOR_TYPES = {
-    'current_status': ['Status', ''],
+    'current_status': ['Status', None],
     'speed': ['Speed', 'MB/s'],
     'queue_size': ['Queue', 'MB'],
     'queue_remaining': ['Left', 'MB'],
diff --git a/homeassistant/components/sensor/transmission.py b/homeassistant/components/sensor/transmission.py
index 62afdd39bf4..26062cbba4d 100644
--- a/homeassistant/components/sensor/transmission.py
+++ b/homeassistant/components/sensor/transmission.py
@@ -15,7 +15,7 @@ from homeassistant.helpers.entity import Entity
 
 REQUIREMENTS = ['transmissionrpc==0.11']
 SENSOR_TYPES = {
-    'current_status': ['Status', ''],
+    'current_status': ['Status', None],
     'download_speed': ['Down Speed', 'MB/s'],
     'upload_speed': ['Up Speed', 'MB/s']
 }
diff --git a/homeassistant/components/sensor/verisure.py b/homeassistant/components/sensor/verisure.py
index e7c6a30b558..dec678677b4 100644
--- a/homeassistant/components/sensor/verisure.py
+++ b/homeassistant/components/sensor/verisure.py
@@ -67,7 +67,7 @@ class VerisureThermometer(Entity):
         return TEMP_CELCIUS  # can verisure report in fahrenheit?
 
     def update(self):
-        ''' update sensor '''
+        """ update sensor """
         verisure.update_climate()
 
 
@@ -96,5 +96,5 @@ class VerisureHygrometer(Entity):
         return "%"
 
     def update(self):
-        ''' update sensor '''
+        """ update sensor """
         verisure.update_climate()
diff --git a/homeassistant/components/sensor/yr.py b/homeassistant/components/sensor/yr.py
index 24f565feb48..08abffb758d 100644
--- a/homeassistant/components/sensor/yr.py
+++ b/homeassistant/components/sensor/yr.py
@@ -21,7 +21,7 @@ REQUIREMENTS = ['xmltodict']
 
 # Sensor types are defined like so:
 SENSOR_TYPES = {
-    'symbol': ['Symbol', ''],
+    'symbol': ['Symbol', None],
     'precipitation': ['Condition', 'mm'],
     'temperature': ['Temperature', '°C'],
     'windSpeed': ['Wind speed', 'm/s'],
diff --git a/homeassistant/helpers/entity.py b/homeassistant/helpers/entity.py
index fd2611889c9..980504d1829 100644
--- a/homeassistant/helpers/entity.py
+++ b/homeassistant/helpers/entity.py
@@ -101,17 +101,18 @@ class Entity(object):
         state = str(self.state)
         attr = self.state_attributes or {}
 
-        if ATTR_FRIENDLY_NAME not in attr and self.name:
-            attr[ATTR_FRIENDLY_NAME] = self.name
+        if ATTR_FRIENDLY_NAME not in attr and self.name is not None:
+            attr[ATTR_FRIENDLY_NAME] = str(self.name)
 
-        if ATTR_UNIT_OF_MEASUREMENT not in attr and self.unit_of_measurement:
-            attr[ATTR_UNIT_OF_MEASUREMENT] = self.unit_of_measurement
+        if ATTR_UNIT_OF_MEASUREMENT not in attr and \
+           self.unit_of_measurement is not None:
+            attr[ATTR_UNIT_OF_MEASUREMENT] = str(self.unit_of_measurement)
 
-        if ATTR_ICON not in attr and self.icon:
-            attr[ATTR_ICON] = self.icon
+        if ATTR_ICON not in attr and self.icon is not None:
+            attr[ATTR_ICON] = str(self.icon)
 
         if self.hidden:
-            attr[ATTR_HIDDEN] = self.hidden
+            attr[ATTR_HIDDEN] = bool(self.hidden)
 
         # overwrite properties that have been set in the config file
         attr.update(_OVERWRITE.get(self.entity_id, {}))