>> Why are we choosing rooftops instead of a central location for solar, like we do for all other types of electricity generation?

solar is different to say coal, because the economics of home-generation, and grid generation are not miles apart. In other words it's not like I can have a coal-fired power station at home, but I can have solar panels. Up to now electricity generation has been constrained to large-scale (hydro, coal, nuclear etc). The advent of solar, and to a lesser extend small-scale wind and hydro, makes local generation more accessible.

>> rather than now having to pay expensive home solar panel loans and maintain them.

Solar maintenance is minimal. (Again, not like a turbine generator.) Loans are a function of capital. It takes capital to populate a home roof, and capital to build a power plant. If you have no capital then the point is moot. As an individual I have enough capital to fund my solar system without loans. (I get about a 14% return on that capital.) I don't have enough capital to fund a power station.

Other benefits of home generation include more resilience should the grid fail. So for example, after a storm, power lines may be down, but I get electricity during the day. That's a bonus though, not the main driver.

So to answer your question - it's not either or, it's both. There's a lot of roof-top solar in my city (measured in gigawatts), there's also solar farms generating power.

Lastly' I'll point out that distribution _from_ my house is cheaper than from a plant, because I generate a few spare kw, and the wire already coming into my hose is sufficient for that. So no new (grid) hardware is required.

> In other words it's not like I can have a coal-fired power station at home, but I can have solar panels.

Not that it matters to your point, but you can, they're just awful — there many reasons why everyone moved away from heating homes with open fireplaces.

(My current apartment in Berlin is old enough to have a chimney, but there's no unit attached to it; likewise the house I grew up in back in the UK has a chimney, but it was bricked off since before I could remember, possibly before I was born).

That’s just heat generation, not power. For power generation a larger generator will be more efficient than a small one.

For heating this does not matter.

Indeed, but that all adds to the reasons why, despite it being possible, nobody does it.

There's relatively little economy of scale in placing solar panels (compared to other energy sources). A lot of the scale advantage has already been achieved by mass producing identical panels.

We are choosing central locations. Google utility-scale solar.

transmission of electricity has losses.

And 2 solar panels only make 2x as much energy if exposure is the same. So go where the sun is already done if the sun is above your head.