Having covered solar in the last couple of episodes, I thought I'd take a look at what to do when the sun doesn't shine. I've been through several generators since I've been afloat - and this is a summary of my experience, thoughts, and conclusions about generators on a narrowboat.
I was asked for costs so here they are. Each item was purchased used off ebay!
B&D genny £220 - it was barely used.
Stephill genny £350 - used in good condition
Diesel genny £200 Well used but ran fine (if somewhat noisily)
Stanley genny £200 - barely used (though not without it's issues!)

The Stephill and the diesel ones were resold, and I recouped my costs.