The Spanish govt paid subsidies for solar cells on Rooves.
People bought them and went 'off grid'.
On grid got so expensive that govts pulled subsidies and started charging the 'off gridders' for being off grid.
They realised that the 'off gridders' were making it more expensive for those left on the grid.
http://reneweconomy.com.au/2015/spa...ar-storage-with-proposed-tax-on-the-sun-45930