[betamaxthetape]

This used to be the case in the UK. There were a few companies that would install solar panels on your roof, at no cost to you. You could use the electricity generated by the panels at no cost.

The catch was that the companies took the feed-in tariff (the government subsidy for generating renewable electricity), and that you needed to commit to having the panels on your house for a minimum number of years (making it unviable if you rented, or planned to move in a few years).

In the mid-2010s the UK changed how the subsidies worked, changing from the feed-in scheme where you were paid per unit of electricity generated (regardless of if you consumed that energy or sent it back to the electricity grid) to the Smart Export Guarantee, where you are only paid for the electricity that you sent back to the grid. According to Wikipedia [0] this caused many of the companies operating the "free solar panels" schemes to go out of business.

[0] https://en.wikipedia.org/wiki/Feed-in_tariffs_in_the_United_...