It would do plenty if you use 12V lighing (two come with the kit) and it could keep re-chargable batteries for flashlighs, radios, PDA, portable DVD and CD players......
You can get a roof top solar system that will run your entire household ......but it will cost +$30k....excess power can be sold to your local utility. They offer tax credits of up to $10k. Your 45watt system looks more like something for a hobbyist. Fun to play with though.