solar panels on every roof for council housing

In a council estate near mine they are spending 5 million on new roofs kitchens, this I feel is money wasted as in these estates are not going to last long. So instead why don't they invest that 5 million on installing solar panels on every roof in the estate?

That way would reduce bills for people and cut emissions this should be a priority for all estates and would help meet our goals of cutting co2 and help people with bills.