If you are behind a proxy, you could try adding CURLOPT_PROXY, for example (assuming your proxy is on 192.168.1.2 port 3128):
$ch = curl_init($geocodeURL);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_PROXY, "192.168.1.2:3128");
$result = curl_exec($ch);
Hope this helps.