We've just moved and inherited a (fake) aga. It is powered by oil and given the rate it is guzzling fuel we can't afford to run it all year round when for half the year it is just pumping out heat we don't want/need. We could turn it off but then we would only have a gas hob to cook on. Whilst we could get an additional cooker as we have lots of space, the kitchen doesn't have a 30amp supply so we can't just add on an extra electric cooker and the gas is calor gas and I've no idea how we might get the supply to an additional gas cooker. It seems like an awful lot of cooking appliances to have in one room when each is only going to be used for six months at a time.
So although there are lots of pros to an aga type we are thinking of getting rid of it and redoing the kitchen at the same time. Good thing we are made of money..... 
Anyway, the problem is that the only other heating source in the kitchen is one radiator near the end of the room. The kitchen is roughly 4.25m by 8.4m so a large space to heat and there are doors to the outside at either end and double glazed windows along one side. So what am I asking? I guess how do I find out how much radiator is needed for a room of that size, anyone got any other ideas re heating or cooking? help i don't really know what to do!