Industrial CCS industrial strategy regional growth cost-competitive CCS Cost Challenge Taskforce CCS Technology CCS Clusters CCUS Spending Review 2015 energy intensive industries CO2-EOR Joint Industry Project carbon £85/MWh oil and gas CCS Costs Phase 2 Delivering CCS CCS Strategy Oil and Gas Authority CCS Clean Growth Strategy CCSA UNFCCC CCUS Cost Challenge Taskforce Cost Reduction low-carbon heat Paris Agreement COP21 CO2MultiStore Energy Bill 2015 hydrogen fifth carbon budget infrastructure CCS Lessons Learned SCCS CCS competition climate change energy demand North Sea