title: Impact Analysis - Heat - Final Report
Creators: name: Gkogka, A.
name: Cooke, H.
Publisher: name: ETI
Year: 2016
Subjects: subject: Energy Storage and Distribution
subject: OTHER CROSS-CUTTING TECHNOLOGIES or RESEARCH (Energy system analysis)

description: This project assessed the potential impact of selected, identified innovations on specific types of network (relating to heat, gas, electricity and hydrogen). Generic modelled networks will be developed utilising the 2050 Energy Infrastructure Cost Calculator model developed by a separate ETI project to understand the expected costs of certain types of network.The modelled networks will provide ‘business as usual data’ and a useful basis for further understanding of the impact of identified innovations in terms of overall cost and network performance.<br><br>This report considers Gas. Key findings are:-Representative Gas Distribution Model: connecting networks to transport sitesat different capacities for different network lengths, in rural, semi-urban, urban and London contextsContext is a strong influencer of costs, with costs increasing from rural through to urban and London. .Pipe costs dominate the overall network cost, particularly for the longer network lengths.Pipe capacity and hence size has some influence over cost at the longer network lengths where pipe costs are the most significant element.Normalised costs (ie costs per km) fall with increasing network length.Generic decommissioning costs (transmission), 100km length at different capacities / pipe sizes, rural contextDecommissioning costs are of the order of £90k/km.Decommissioning of the pipework comprises around 80%-85% of cost, with the remaining 15%-20% relating to decommissioning the conversion station.Pipe size has a minimal impact on cost.Generic decommissioning costs (distribution)for different contexts and populationsDecommissioning costs range from around £250k/km in London down to £60k/km in rural areas.The relative importance of the different Assemblies in terms of share of cost varies with context: decommissioning the LP network represents the largest share of cost in rural areas (60%) and decommissioning domestic connections represents the largest share of cost in London areas (58%)Generic operational costs associated withremaining part of apartially decommissioned network (distribution)In each context, reduction in Opex with increasing decommissioning is linear.Direct costs represent approximately 80% of the overall Opex for gas distribution infrastructureDecommissioning (abandonment) costs make up a small share of overall costAfter partial decommissioning, NPV of the partially decommissioned network per connection served increases as the percentage of network decommissioned rises.Gas transmission network: repurposing to hydrogen for different network lengths in a rural contextOverall the innovation of repurposing existing natural gas transmission networks to carry hydrogen is roughly half the cost of abandoning those same networks and building hydrogen pipelines from scratchGas transmission network: repurposing to carbon dioxide for single network length in ruralThe task compared repurposing existing gas transmission pipelines to carry gas phase CO<sub>2</sub> compared with building new transmission pipelines to carry dense phase CO<sub>2</sub>.Although operational conditions of pressure and and semi-urban contexts were different, they maintain the same CO<sub>2 </sub>capacity flowBoth first costs and NPV are higher for new build than for repurposing.All costs are higher in a semi-urban context than a rural oneNatural gas conversion: installation of Biomethane to Grid injection points with different network lengths and capacities in rural and urban contextsThe cost of installing Biomethane to Grid plant is higher in urban areas than in less dense rural onesNormalised costs per km fall with increasing network lengthNormalised costs per m<sup>3</sup> gas decrease with increasing gas injection capacities