by Anthony Harrington
One of the perennial issues for owners of grid-connected renewable power
generation assets is the obligation to comply with National Grid’s
instructions to stop pumping electricity into the grid when there is
over-supply. Of course, this is just one of any number of maintenance tasks
that come with ownership of renewable power generating assets.
However, as Pieter D’haen, Commercial Director at the renewables
consultancy, Natural Power, explains, perhaps the easiest way of responding
to instructions from National Grid is to outsource the management and
maintenance of the asset to a specialist provider. Natural Power runs a
grid ControlCentre at its offices near Castle Douglas where it manages some
30 per cent of the UK’s installed wind power.
“The UK has very strict wind turbine safety rules. Any activity on a wind
farm site has to be monitored to ensure the highest standards of safety for
any staff. Above all, you want to make sure that the turbine is not
restarted while staff are still in the vicinity,” D’haen notes. All the
client has to do is to call Natural Power’s ControlCentre for permission
for maintenance staff to go onsite and the company can then shut down the
turbine and log the visit and the reason. This provides a clear safety
record for all visits to any of the sites monitored by the Centre.
“Our ControlCentre is manned round the clock, we also look after a number
of high voltage lines and grid infrastructure items from the Centre,” he
Natural Power has a very close relationship with National Grid and will act
on all instructions from them, stopping wind farms and turning them back on
as capacity dictates. While a large number of clients are onshore, the
Centre also looks after a number of offshore assets.
“The infrastructure that runs from the wind farm to the shore, along with
the shore based station, is owned by the offshore transmission operator,
and they generally look to outsource the management of those assets. We
already look after these types of asset for some seven offshore operators
and we are the biggest caretaker of offshore assets,” he notes.
It might seem as if undersea cabling would require little intervention, but
it can require a surprising number of resets over time to cure minor faults.
“We have expanded our capacity in the sector and we will be opening our new
ControlCentre. We carried out an upgrade of our systems so that we can
respond to hundreds of instructions from National Grid. We have some 35
monitors and 10 control desks where operators monitor client networks day
and night,” he notes.
The operational control and monitoring of wind farms is just a part of the
portfolio of services that Natural Power provides. It has a well
established maintenance section where engineers carry out maintenance work
on windfarms. “When turbines come out of warranty or the existing
maintenance contracts come to an end, we’ll bid for the contracts. This is
a very competitive business now,” he notes.
He points out that one of the advantages the company has in bidding for
such contracts is that the depth of experience in the company means it can
work on a range of turbine types and can respond very quickly to faults
across the UK. “We did a study recently which showed we were able to help
clients reduce energy output losses through the winter. This helps the
operator to drive the cost of energy production down and helps to increase
the performance of the asset.”
It is hard to overstate the importance of driving down generation costs for
onshore wind. The sector has been knocked back by the UK Government’s
decision to withdraw subsidies from onshore wind. “The onshore wind sector
is something of a victim of its own success. For the last 10 to 15 years it
has been very successful at driving down the cost per kilowatt hour. We
have had bigger turbines and better optimized turbines and there have been
real cost reductions. However, it remains a struggle to get new onshore
wind farm projects funded without investors being able to see some
underwriting of future revenues by Government,” he notes.
It is not the difficulties of competing in a zero-subsidy generation
environment that is causing the problem for new projects. D’haen points out
that there is now a feeling in the sector that onshore wind has matured to
the point where it can compete without subsidy. But onshore wind farms are
capital-intensive projects, with the bulk of the cost being borne upfront
in the construction phase.
“Upfront capital costs are a real disincentive. Instead of withdrawing
subsidies totally, government would perhaps have been better advised to
have worked out some kind of initial capital grant. The lack of new
projects is a problem that will need to be addressed,” he notes.
The alternative for the owners of a proposed new onshore wind farm would be
to secure a long-term purchase contract for their power from a large
corporate. However, as D’haen observes, such deals are few and far between.
“What we are suggesting to government is that they offer to provide
contracts for difference (CfDs) guaranteeing, say, £40 a kilowatt hour.
Investors are less risk averse than banks so even that low level of
guarantee would be enough to give them sufficient confidence to back
projects. It is very unlikely that the market price would fall below that
level so the whole thing would more than likely be cost-free to
government,” he comments.
What the onshore wind sector needs is a framework from government that
enables projects to go forward, once again. “This is how companies in
Germany and elsewhere are able to get new projects and these countries are
seeing reductions in the generating costs,” he notes.
Despite the difficulties, D’haen says that Natural Power is advising on a
number of proposed projects that are looking at the viability of operating
purely on market pricing or by securing long term corporate power
purchasing agreements in advance of construction.