Climate for Change
There are plans for a new 50 megawatt battery storage facility at Whitelee
Renewable energy’s contribution to the generation mix continues to grow.
However, it still faces one major challenge. Producing green electricity is
one thing, but storing it is quite another.
The problem? It’s the weather, stupid. Scotland may be the windiest place
in Europe, but that wind isn’t consistent. When it blows, the turbines
turn, but you don’t always get a breezy force five when and where you need it.
The answer lies in saving the power on blustery days and then using it on
calmer ones. That means battery storage. This may sound a profoundly simple
solution, but until now, its rollout has been hindered by technical
challenges and the cost of the infrastructure.
However, things are changing. Scottish Power has announced plans for a 50
megawatt battery storage facility at its Whitelee wind farm on Eaglesham
Moor outside Glasgow – the biggest in the UK. And another company, RES, is
managing a 20 megawatt storage centre at Broxburn, West Lothian, the first
of its type in Scotland, on behalf of The Renewables Infrastructure Group
We are still catching up with the United States, where some 1.4 gigawatts
of batteries have been deployed in the last year alone. But there is plenty
of optimism. “Our Broxburn project has been operational since last summer,”
says Tim French, RES’s Head of New Technology. “It’s been very successful,
operating at high levels of availability. The customer, National Grid, is
RES has its own Glasgow-based control system that manages the batteries
intelligently and assists with the operation and maintenance.
The stored power is available 24/7 and feeds into the grid automatically
when demand exceeds supply. The energy is stored in thousands of individual
but connected lithium-ion battery cells, stacked in arrays within
containers. These cells have high capacity and respond quickly when needed.
Deploying power in this way is not just environmentally friendly – it has a
positive economic impact, too. National Grid calculates that battery
technology will save it some £200 million, which will ultimately feed
through in lower costs to the end user. This is because this stored and
readily available green energy avoids having to use other, more expensive
generating options to keep supply stable.
“Because the batteries can respond in super-quick time, the grid does not
have to switch into these other sources,”
Tim French explains. “We use lithium- ion technology because it’s very good
at this kind of application. It is able to charge and discharge very
quickly and the energy density within each cell is quite high.”
The combination of renewable power and flexible storage is reckoned to
provide the most cost-effective low carbon solution for consumers. Another
Scottish energy giant, SSE, is also trialling lithium-ion storage including
for solar panels, researching if it could be a cheaper solution than
building new transmission lines.
“The chemistry has been around for a while, with lithium-ion used in all
sorts of applications over the last decade or so, but the main reason
battery storage is now revolutionising the market is cost.
RES currently have more than 1,000 MW (megawatts) of renewable energy
projects constructed, under construction or at advanced planning stages.
“This has come down by as much as 50 per cent in the last three or four
The ultimate aim of this technology is to allow the complete phasing out of
fossil fuel generation over time. “We believe that can happen,” says Tim
“Obviously, we’re on a journey, but one would hope that we could move
quicker than we have until now. By 2030, we’d like to see fossil fuels off
One issue which still needs to be fully addressed is not just how much
power can be provided, but for how long. Typically, batteries can currently
feed into to the supply for one to four hours before they become exhausted.
This is enough most of time, but other technologies are still needed in
order to prove more longevity.
Different types of energy storage are already available, and some have been
around for decades. The venerable Ben Cruachan pump hydro scheme on the
shores of Loch Awe near Oban, for instance, has been generating power
through water and gravity since 1965.
Other solutions include supercapacitors, solid state and lithium-air.
These can be more suitable for short duration, high power applications.
However, lithium-ion is likely to be the lead technology over at least the
next five to 10 years, largely because it is seen as a relatively mature
solution which gives comfort to investors. Cost is also likely to continue
Interestingly, lithium-ion is also the same storage solution used for
electric vehicles (EVs), the use of which is expected to grow incrementally
in coming years, with predictions of 230 million of them on the road across
the globe by 2030.
Rachel Ruffle, who is the Managing Director of RES, share Tim French’s
vision for the Broxburn facility and the wider industry.
“We believe this project will play an important role. Energy storage can
play a large part in supporting the transition to a secure, low carbon, low
This article appeared in The Herald on the 14th March as part of The
Heralds weekely Climate for Change editorial.
The Herald’s Climate for Change initiative supports efforts being made by
the Scottish Government with key organisations and campaign partners.
Throughout the year we will provide a forum in The Herald newspaper, online
at herald.scotland.com and in Business HQ magazine, covering news and
significant developments in this increasingly crucial area.