Home generation using micro CHP is one option, but the economics generally rely on long running hours to cover baseload electricity demand, and finding a use for all the waste heat.
The fundamental issue with going down the CHP route is that it makes it difficult to decarbonise domestic heating unless you have a source biogas which would at least be theoretically near net zero CO2/kWh. Accordingly, I'd prefer to work towards an all electric solution for space heating and a solar hot water/electric immersion top-up solution for domestic hot water.
A new Baxi Ecogen wall hung micro CHP has an installed cost of circa £4500, plus you'd probably want to add in some smart controls to ensure various devices around the house make best use of the power/heat. But as previously discussed it won't produce all your power, and in the summer you'd need to shut it down otherwise you'll have pointless waste heat (unless you have a hot tub, pool or cannabis farm). It would (currently) earn you some feed-in tariff pennies.
The longer term "green" solution would be a ~4kW solar PV install, which just tucks in under the G83 connection regulations, and a battery storage system (Tesla Powerwall or one of the many similar systems). Combined with products from companies like
http://myenergi.uk/ to manage power use and export in a smart way, this could meet a lot of your daily needs (certainly between spring and autumn). The combined system might deliver 70% of your power needs over the mid summer, and on average ~50% across the year. If the battery system can automatically work in "island" mode, this also gives you some resilience in the event of grid power outage whereas a CHP would stop operating if mains power to it's electronics is lost.
There are other products out there like BlueGen which is a fuel cell CHP, the outputs of which are skewed much more towards power generation rather than heat. But, it's big and really aimed at small commercial needs and as part of a bivalent (hybrid) system in which power demand is >10000 kWh/year.
If you have a high heating demand, year round (e.g. swimming pool) then you could readily combine a small CHP with other systems to really get the benefits. Consider:
* small CHP to produce electricity and earn a little bit of Feed in Tariff.
* use the electricity produced to power an air source heat pump (to generate additional heat) and use the waste heat from the CHP too. The ASHP should also qualify for Renewable Heat Incentive.
https://www.renewableenergyhub.co.uk/micro-combined-heat-and-power-micro-chp-information/the-baxi-ecogen-microchp-boiler.htmlhttp://www.solidpower.com/en/bluegen/https://www.ofgem.gov.uk/environmental-programmes/fit/fit-tariff-rates