[ResearchAtPlay]

148 g/km seems to be the default number. I got that same number for two different routes that were entirely located within British Columbia and Alberta, respectively. The problem is that British Columbia has an electricity emissions intensity of about 30kg/MWh while Alberta's is about 600kg/MWh. Hence, this website does not use correct electricity emissions data.

Maybe you can partner with the folks over at https://www.electricitymap.org/ to improve the emissions data?