In reply to maxsmith:
A micro sewage treatment plant is an option - about £15k from memory but does need a reasonable amount of electricity for the plant in them (stirring motor I think). Electric supply would be an issue in winter. I’m not sure how well they deal with very intermittent use.
Theres a few people in the USA who sell bacterial digesters with toilet coupling; no idea on legislation in the UK and again they’ll not like being rarely used.
Our local wildfowl and wetlands trust has a modern composting toilet so it is possible. I’d want it in a separate outhouse due to smells however!
You could have macerator and a waste tank that you empty periodically by vehicle.
Bimble solar sometimes have great deals on used solar panels - typically from early upgrades on big solar farms caused by some panels getting storm damaged. Save money and materials by going for “in roof” panel mounting. I’d put way more in than you need if you can possibly afford it. More power is always useful, and it helps you through cloudy days and days far from summer. A free standing mast with a 1 kw wind turbine on it would go a long way towards winter habitability. If I was doing the energy system design I’d add the ability to take power from electric vehicles as another fallback for winter; we have similar at home but it’s too much of a bodge to be standardised or for me to be happy opening it to others. Fast developing area though.
I’ve looked at all the ruins around me - one day in 50 years time with magic flying cars and the ever reducing cost of off grid living, they’re a potential goldmine - beyond my life expectancy probably...
Most UV water purifiers use very old school lamps that don’t survive being turned off and on regularly so you need to budget the power to keep it on 2;x7 throughout the season and to replace the lamp each year. When I last looked LED based units were just coming to market in the USA - much better. You’ll need sub-micron filtration before the UV, and you’ll need to be able to drain all the filters etc before an unheated winter period.
My biggest regret with a rainwater system is not having set it up with a submersible pump - when space is tight that’s a great space saver and reduces the number of couplings that can leak inside the building, as well as providing better ice protection than an unheated building.
Post edited at 19:55