RE:RE:RE:RE:RE:RE:RE:Barging questionsThe reason for the discount is that TAL's oil originaly had an API of 18.5 whereas a light oil would be an API of 35 to 40. This is very much standard. Good news here is recently tested oil has seen an improvement to 19.5.
Here is Wikipedia's summary:
Classifications or grades[edit]
Generally speaking, oil with an API gravity between 40 and 45° commands the highest prices. Above 45°, the molecular chains become shorter and less valuable to refineries.[4]
Crude oil is classified as light, medium, or heavy according to its measured API gravity.
- Light crude oil has an API gravity higher than 31.1° (i.e., less than 870 kg/m3)
- Medium oil has an API gravity between 22.3 and 31.1° (i.e., 870 to 920 kg/m3)
- Heavy crude oil has an API gravity below 22.3° (i.e., 920 to 1000 kg/m3)
- Extra heavy oil has an API gravity below 10.0° (i.e., greater than 1000 kg/m3)
However, not all parties use the same grading.[5] The United States Geological Survey uses slightly different ranges.[6]
Crude oil with API gravity less than 10° is referred to as extra heavy oil or bitumen. Bitumen derived from oil sands deposits in Alberta, Canada, has an API gravity of around 8°. It can be diluted with lighter hydrocarbons to produce diluted bitumen, which has an API gravity of less than 22.3°, or further "upgraded" to an API gravity of 31 to 33° as synthetic crude.[7]