Drupal rule to provide free shipping on all shipping services using calculation rules.

commerce-free-shipping.json

{ "rules_free_shipping_offer" : {
    "LABEL" : "Free Shipping offer",
    "PLUGIN" : "reaction rule",
    "REQUIRES" : [ "rules", "commerce_line_item", "commerce_shipping" ],
    "ON" : [ "commerce_shipping_calculate_rate" ],
    "IF" : [
      { "data_is" : { "data" : [ "commerce-line-item:type" ], "value" : "shipping" } },
      { "data_is" : {
          "data" : [ "commerce-line-item:order:commerce-order-total:amount" ],
          "op" : "\u003E",
          "value" : "15000"
        }
      }
    ],
    "DO" : [
      { "commerce_line_item_unit_price_amount" : {
          "commerce_line_item" : [ "commerce_line_item" ],
          "amount" : "0.00",
          "component_name" : "shipping",
          "round_mode" : "1"
        }
      }
    ]
  }
}