1. What has happened since 2015?
Preesall Underground Gas Storage Scheme
What has happened since 2015?
Market drivers
Technical Development
Contract Strategy
Legacy Brinewell Management

2. Market Drivers Renewable generation continues to expand 20% and rising
Preesall Underground Gas Storage Scheme
Market Drivers
Renewable generation continues to expand
20% and rising
Intermittent generation need expanding
UK gas storage depleted by Rough closure
70% of UK storage lost
13 days down to 4 days
GREATER NEED FOR FAST CYCLE STORAGE

3. Technical Development
Preesall Underground Gas Storage Scheme
Technical Development
Surveys have been undertaken and continue
Operational requirements modelled in detail
DCO compliance commenced
SECTION 106
Regulatory authorities engaged

4. Construction Strategy
Preesall Underground Gas Storage Scheme
Construction Strategy
Delivery strategy developed
Contracts for advanced works being let
Haul road
Brine pipeline
Construction starting in 2018 (Q1)

5. Way Forward Preesall Underground Gas Storage Scheme DCO Decision
July 2015
Project Delivery Planning
Jan-Dec 2016
Liaison, Surveys, Design and Consents
Phase 1 Construction
First Gas
2020   
Brine outfall
Electricity supply
NTS connector
Gas compound
Wellhead compounds etc
Cavern washing
Approvals & operation
Preesall Underground Gas Storage Delivery 5

6. Legacy Brinefield Management
Preesall Underground Gas Storage Scheme
Legacy Brinefield Management
Halite has continued to manage legacy brinefield
Monitoring
Maintenance
Blow out risk
Collapse risk
Subsidence
Well pressures

7. Legacy Brinefield Management
Preesall Underground Gas Storage Scheme
Legacy Brinefield Management
Meeting the HSE annually
Meeting other interested parties
Repairing wellheads
Maintaining fences & tracks
Since 2015 >£250,000 spent

9. In the UK gas is stored underground in: Caverns Depleted reservoirs
Preesall Underground Gas Storage Scheme
SAFETY
In the UK gas is stored underground in:
Caverns
Depleted reservoirs
Pipelines (Linepack)

10. Preesall Underground Gas Storage Scheme
SAFETY

11. Preesall Underground Gas Storage Scheme SAFETY
Normal Rock
Salt

12. At least 300m below the ground surface Shaped for stability
Preesall Underground Gas Storage Scheme
The Caverns
Up to 19 caverns
100m diameter
50m to 200m tall
At least 300m below the ground surface
Shaped for stability
Roof cone
Main chamber
Sump

13. Preesall Underground Gas Storage Scheme
How the Caverns are constructed

14. Salt has a very low porosity Salt has a very low permeability
Preesall Underground Gas Storage Scheme
SAFETY
Why is salt safe?
Salt has a very low porosity
Salt has a very low permeability
Salt is self healing therefore does not fracture like normal rocks
Salt is strong
Gas has been stored in caverns for more than 50 years and there is no case of gas leakage from salt caverns

15. Salt Cavern Fast Cycle Gas Storage
Preesall Underground Gas Storage Scheme
SAFETY
Salt Cavern Fast Cycle Gas Storage
‘huff ‘n puff’
Its most distinguishing characteristic is deliverability (mcm/d), not working gas volume or space
Carbon – shallow salt strata, rapid volume in and out of storage means low energy costs and low CO2.

16. Way Forward Preesall Underground Gas Storage Scheme DCO Decision
July 2015
Project Delivery Planning
Jan-Dec 2016
Liaison, Surveys, Design and Consents
Phase 1 Construction
First Gas
2020   
Brine outfall
Electricity supply
NTS connector
Gas compound
Wellhead compounds etc
Cavern washing
Approvals & operation
Preesall Underground Gas Storage Delivery 16