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