a big factor here is dogs. if you have your pet with you on a lead, and there are calves(baby cows) in the field, sometimes a normally docile cow herd will be very protective of their offspring. generally if there is no dog, cows realise you are not a threat.
the article states that drax burning wood produces four times the CO2 of radcliffe burning coal; however it fails to mention how much electricity was produced by each one. i expect better from the guardian, but we didn’t get it in this report.