Did you read the last part, if not here it is: "but these are relatively small."
Subsidies are decomposed into explicit and implicit subsidies. Explicit subsidies occur when the retail price is below a fuel’s supply cost. For a non-tradable product (e.g., coal), the supply cost is the domestic production cost, inclusive of any costs to deliver the energy to the consumer, such as distribution costs and margins. In contrast, for an internationally tradable product (e.g., oil), the supply cost is the opportunity cost of consuming the product domestically rather than selling it abroad plus any costs to deliver the energy to the consumer. Explicit subsidies also include direct support to producers, such as accelerated depreciation, but these are relatively small.