> Tesla is responsible for 5% market share... that is nowhere near the leader.

My understanding is that a market leader has the largest share among competitors, not a majority. If the next largest company only has 4.5% of the market, then Tesla/SolarCity is the leader.

That being said, if Tesla is the leader then competition is fierce and the market is ripe for consolidation.

The solar installations market is broken down into residential (where SolarCity might be the leader), commercial (office parks) and utility scale.

Residential is the largest by quantity of installations, but when you look at the total production numbers, utility-scale easily blows everyone away https://en.wikipedia.org/wiki/List_of_photovoltaic_power_sta...

First Solar sold 6GW of solar in 2017 in the US alone. Admittedly, that's not installed (current production capacity is around 3GW per annum), but their largest individual installation is 280MW, about half of Tesla's total production.

First Solar is merely the largest US-based solar company; some Chinese companies are even larger in terms of volume.

SolarCity was, until fairly recently, the leading residential solar provider (it's a crowded market, so leading doesn't mean a huge market share like it does in, say, the mobile OS market). For cash position reasons they pivoted away from leases, which cost them the lead to Sunrun, because leases are still a big part of the market.