diff --git a/checks/__init__.py b/checks/__init__.py
index 3d1d5a5..3065c04 100644
--- a/checks/__init__.py
+++ b/checks/__init__.py
@@ -21,6 +21,7 @@ from checks import load_in_browser
 from checks import page_content
 from checks import url_canonicalization
 from checks import url_reachability
+from checks import green_power
 
 from checks.config import Config
 
@@ -50,6 +51,7 @@ def perform_checks(input_url):
         ('load_favicons', load_favicons),
         ('load_feeds', load_feeds),
         ('load_in_browser', load_in_browser),
+        ('green_power', green_power),
     ]
 
     results = {}
diff --git a/checks/green_power.py b/checks/green_power.py
new file mode 100644
index 0000000..4f448ab
--- /dev/null
+++ b/checks/green_power.py
@@ -0,0 +1,56 @@
+"""
+This check looks up the domain of site against the Green Web Foundation API,
+to confirm that sites in the green party, run on green power, rather
+than fossil fuels.
+"""
+
+import logging
+
+import requests
+from urllib.parse import urlparse
+
+from checks.abstract_checker import AbstractChecker
+
+logger = logging.getLogger(__name__)
+
+
+class Checker(AbstractChecker):
+
+    API_ENDPOINT = "http://api.thegreenwebfoundation.org/greencheck/"
+
+    def __init__(self, config, previous_results=None):
+        super().__init__(config, previous_results)
+
+    def run(self):
+        """Executes the check routine, returns result dict"""
+
+        results = {}
+
+        urls = list(self.config.urls)
+        for url in urls:
+            hostname = urlparse(url).hostname
+            results[url] = self.check_for_green_power(hostname)
+
+        return results
+
+    def check_for_green_power(self, url):
+        """
+        Checks the url passed in agains the Green web Foundation API
+        to see if the domain known to be running on green power.
+        """
+        # use the "big tarp" to catch the error, but don't crash the program
+        # returning false because we didn't come back with any  evidence that
+        # the site uses green power
+        # more on the big tarp:
+        # https://www.loggly.com/blog/exceptional-logging-of-exceptions-in-python/
+        check_url = f"{self.API_ENDPOINT}{url}"
+
+        try:
+            result = requests.get(check_url)
+            return result.json().get('green')
+        except Exception:
+            logger.exception("Requesting data from the API failed")
+
+            return False
+
+
diff --git a/checks/green_power_test.py b/checks/green_power_test.py
new file mode 100644
index 0000000..dec9ec8
--- /dev/null
+++ b/checks/green_power_test.py
@@ -0,0 +1,22 @@
+import unittest
+
+from checks import green_power
+from checks.config import Config
+
+class TestGreenPower(unittest.TestCase):
+
+    def test_is_green(self):
+        """Check that we get a green result for green powered site"""
+        # google is green, Koch Industries. predictably is not
+        # TODO mock the result, so we don't need to hit a live API
+        config = Config(urls=['https://google.com/'])
+        checker = green_power.Checker(config=config)
+        result = checker.run()
+        self.assertEqual(result['https://google.com/'], True)
+
+    def test_is_not_green(self):
+        """Check that we get a grey result for grey powered site"""
+        config = Config(urls=['http://www.kochind.com/'])
+        checker = green_power.Checker(config=config)
+        result = checker.run()
+        self.assertEqual(result['http://www.kochind.com/'], False)
\ No newline at end of file
diff --git a/rating/__init__.py b/rating/__init__.py
index 4d247b5..9c09097 100644
--- a/rating/__init__.py
+++ b/rating/__init__.py
@@ -22,6 +22,7 @@ from rating import responsive_layout
 from rating import social_media_links
 from rating import use_specific_fonts
 from rating import www_optional
+from rating import green_power
 
 
 def calculate_rating(results):
@@ -51,6 +52,7 @@ def calculate_rating(results):
         'SOCIAL_MEDIA_LINKS': social_media_links,
         'USE_SPECIFIC_FONTS': use_specific_fonts,
         'WWW_OPTIONAL': www_optional,
+        'GREEN_POWER': green_power,
     }
 
     output = {}
diff --git a/rating/green_power.py b/rating/green_power.py
new file mode 100644
index 0000000..d6ee97d
--- /dev/null
+++ b/rating/green_power.py
@@ -0,0 +1,31 @@
+"""
+This checks the result for an url using green power, and returns
+a boolean based on whether it's using green power or not
+"""
+
+from rating.abstract_rater import AbstractRater
+
+class Rater(AbstractRater):
+
+    rating_type = 'boolean'
+    default_value = False
+    depends_on_checks = ['green_power']
+    max_score = 1
+
+    def __init__(self, check_results):
+        super().__init__(check_results)
+
+    def rate(self):
+        value = self.default_value
+        score = 0
+
+        if check_results['green_power']:
+            value = True
+            score = self.max_score
+
+        return {
+            'type': self.rating_type,
+            'value': value,
+            'score': score,
+            'max_score': self.max_score,
+        }
\ No newline at end of file