That article is quoting the cost of halogen heaters at a max output 1500 Kw.
I have the halogen heater on its lowest 400 Kw setting which costs about 12p an hour - compare that with the running costs of oil filled rads and electric fires.
The electric fires and oil filled rads give CONVECTED heat. Halogen heaters give RADIANT heat and when near a person in a small room provide adequate heating for comfort at the lowest setting for the cheapest cost.
It's really very simple.