This document summarises the findings of an external independent review of the storage plan for
the proposed Peterhead Carbon Capture and Storage project which aims to store up to 20 million
tonnes (Mt) of CO2 within the framework of the European Directive on the geological storage of
CO2.
The Peterhead Carbon Capture and Storage Project proposes to capture carbon dioxide (CO2)
from an existing gas-fired power-station at Peterhead and to store this in geological strata at a
depth of around 2600 m beneath the outer Moray Firth. The plan is to store 10 - 15 Mt of CO2
over a ten to fifteen-year period commencing around 2020, but the site is being qualified for 20
Mt to allow for potential extension of the injection period. Storage will utilise the depleted
Goldeneye gas condensate field with the Captain Sandstone reservoir as the primary storage
container. The Storage Site covers some 70 km2, and comprises the Captain Sandstone and
underlying strata of the Cromer Knoll Group, bounded by a polygon some 2 to 3 km outside of
the original Goldeneye oil-water contact. The Storage Complex is larger, around 154 km2,
bounded some 2 to 7 km outside of the original oil-water contact, and extending upwards to the
top of the Dornoch Mudstone at a depth of more than 800 m. The top-seal of the primary
container is a proven caprock for natural gas and is formed by the mudstones of the Upper
Cromer Knoll Group, the overlying Rodby and Hidra formations and the Plenus Marl. A number
of additional seals are present in the overburden within the Storage Complex, as are a number of
potential secondary containers which could also serve as monitoring horizons.
The geological interpretation of the storage site is based on the comprehensive datasets acquired
during the discovery, appraisal and development of the Goldeneye field, and also data from other
wells, fields and seismic surveys in the surrounding area. The static geological model of the
storage site and adjacent aquifer has been stress tested for the key uncertainties, and it is
considered to be robust. The storage capacity of the Goldeneye structure has been calculated
using both static (volumetric) methods and dynamic flow modelling together with uncertainty
analysis. Total estimated capacity of the structural closure is in the range 25 to 47 Mt and so
robustly exceeds the proposed injected amount.