Government spending is only useful for creating the infrastructure for the private sector (the police, army, NHS, schools etc.), government can't generate wealth itself. It's the private sector that creates real wealth. Too much government means the private sector can't support it, and the nation ends up in debt. Too little government and the private sector doesn't have the infrastructure to survive. Government can *never* create productive jobs.
Don't even get me started on the perverse incentives of the Green Deal. A few months ago, I insulated my roof. Now, as I understand it, I will be forced by law to pay extra for my electricity, in order to subsidise those without insulation. Not fair, and an example of big government sapping the initiative of the individual.
Let's have a carbon tax-back scheme instead.