I have been able to authenticate using the json file associated with a service account using googleAuth and bigQueryR.
googleAuth
bigQueryR
# Load Packa
You can use the function set_service_token()in bigrquery to authenticate with the same service JSON you use in bigQueryR
set_service_token()
bigrquery
library(bigrquery) set_service_token("location-of-service.json")
Source: https://github.com/rstats-db/bigrquery/issues/22