Storage radiators are a pretty useless way of heating a house, as they are stone cold when you need that heat, in late afternoons and evenings. But of course, they may be your only option if you are not on the gas main.
However, I have recently started using one of those Halogen room heaters. They are very cheap, as they can be run on only 400w, which is just about OK for a small room. I found one on ebay for £12 including p+p.
They take up hardly any room and can easily be moved about. At £12 its got to be worth investigating.