In the news

Oooh.. look at me, just by owning a little boat I am so much better than you!

That article presents A LOT of motivated reasoning behind each claim that they are greener than the average East London resident. There's a complete absence of any side by side numerical analysis.

OK, I will buy the argument about them producing less rubbish. Seems reasonable.
But is their system for disposing of portaloo waste better than me flushing my shit down the municipal sewage system? I don't know the details of the boat dwellers' human waste disposal, but from what I've read about third world slums, a piped sewage system is always considered an improvement. The alternative is often lorries transporting tanks full of poo from place to place.
At least one of the residents has the honesty to admit that her dishwater goes straight into the canal, so us flat dwellers clearly win there. The boat dweller claims to use some greener form of washing up liquid, but again I would like to see proof other than the manufacturer's own claim.
Canal boats typically have smaller spaces to heat up, fair enough, but I would still expect that most council estate flats conserve energy better than these boats. So any savings by living small might easily be cancelled out by the boat's poor insulation. And burning coal in a residential area? Fuck off. I keenly remember my morning commute past the these boats when I lived in Hackney Wick. My impression is that most boats send their smoke straight into the atmosphere with little or no filtering involved.