Cheap electricity (just cents / kWh) from CHP appliance

Cheapest power by far are my two solar panels on my shed roof. Installed in 2015. They're only 250W each, so I only get about 1 full battery worth per month in the spring/summer/fall but one day I will have more and hopefully they will be more efficient too.

 

Which ever way you choose to go, solar/wind/water power, you're basically deferring the electricity payments for however long it takes to get the ROI.
We are just the two of us and have a 10kw solar system, 1900sqft house, the KONA plus wood/metal working shop and have been electricity neutral for the past 3 years. In BC the power that gets sent back to the grid is credited to your electricity account, we bank enough kw credits during the summer to get us through the winter. We figure with the savings in electricity/gasoline our ROI will be about ten years if there are no major repairs to deal with. I don't include the cost of the car because it's easy to spend $60k+ on a pickup so the cost of the car is on par with a lot of popular ICE vehicles.