Abstract
Tidal stream energy (TSE) is an emerging renewable energy source that could make a meaningful
contribution to global net zero ambitions. Compared with other renewable energy sources, a key
benefit of TSE is that it is highly predictable, both in terms of the quantity and timing of its power.
This could provide crucial balancing support to electricity grids, particularly as more intermittent
renewable energy generation sources are added to networks. In the case of the UK, studies have
shown that TSE could lower the costs of operating the energy system in the order of £100m - £1bn
per year, due to reduced requirements for grid upgrades, storage systems and electricity
imports.
The predictability of TSE also lends itself to alternative offtakes that have consistent demand and
require stable energy supply and costs. Preliminary studies have shown that TSE could be highly
effective for green hydrogen production and the replacement of fossil fuel generation in off-grid
communities.
This study investigates the feasibility of using TSE to meet the energy demands of data centres, which
are increasingly being built to run digital services necessitated by modern society, including AI and
cloud computing. A key challenge to this rapid development is that data centres require significant
amounts of electricity. For example, data centres currently consume around 2.5% of the UK’s
electricity and this is expected to rise four-fold by 2030. This has put additional pressure on already
strained grid infrastructure. Limited grid capacity means it can take years to get permission to
connect to the national grid.
There are also concerns about the sustainability of data centres. Major data centre operators have
committed to achieving voluntary sustainability targets by 2030. They support renewable energy
projects through green power purchase agreements (PPA), although it is disputed whether green
PPAs contribute to tangible decarbonisation. Some operators have co-located wind and solar with
data centres to meet a portion of their energy demands, while others are exploring nuclear power,
including small modular reactors, as a source of clean, reliable power.
The assessment presented here considers a range of TSE scenarios combined with a battery energy
storage system (BESS) to evaluate the effectiveness of this arrangement in meeting the energy
demands of a data centre. A logic model was developed to determine how power should be
distributed between the combined tidal-BESS-data centre arrangement.