We pay less than that in a house of 4 people, I'm at home 5 days a week, older house, teenage + school aged daughters. We live in SA so the price per kWh is more here than anywhere. BUT we have a gas space heater as main living area heating. I understand there are some highly efficient panel style heaters that are much cheaper to run, it might be worth lashing out a couple of hundred on one of those to save a lot more on power over the life of the heater. In the meantime, turn the heater's thermostat down and turn it off an hour or so before you stop using it because it will keep putting out heat for a while.

Also, look at the power settings on your laptop, set up the screen to power down to a low power setting after 10 mins of not using it, and to "sleep" when you're not on it during the day (saves power but starts up quicker). Also if you're using a modem, install a timer on it to switch it off when you're not using it. We have all this stuff set up to happen automatically. I don't mind paying for electricity we use, but i mind very much paying for power that is just leaking away for no reason.