Duncan Burt, Customers services manager at National Grid, explains how the Grid is working with Government and industry to improve wind connection.

Staff Writer

WindEnergyUpdate: How are you planning to manage the offshore wind boom over the next 5-10 years in terms of transmission and distribution?

Duncan Burt: Offshore wind over the next five to ten years really is focused on transmission, both with the Crown Estate’s Round 3, and with the Scottish territorial waters round and further with the Pentland Firth marine energy development, up in the North of Scotland. The key driving work behind that in terms of network design is the ENSG (Electricity Network Strategy Group) work. The challenge here is that there’s potentially a lot of network to build and a lot of complexity to look at in a short amount of time. Five to ten years in terms of major infrastructure build means now, so we need to be getting on and doing it. The ENSG looks at what network solutions we’ll need onshore and potentially offshore with the undersea cables from Scotland to England, to accommodate high levels of on and offshore renewables built over the next ten years.

The ENSG was done jointly with Government and with Ofgem, with industry stakeholders from across the generator community, and the three transmission owners onshore: ourselves, Scottish Power transmission and Scottish hydroelectric transmission.  That work has identified a set of tranches of investment, some of which we should be getting on with straight away, the second tranche which is the strong need case and the third tranche which we don’t need to action on now. The headline items are the two undersea connecting cables between Scotland to England and Wales, an east coast and west coast connector.

We’re also working very closely with Ofgem on proposals for funding anticipatory investment. Normally we wouldn’t build new networks until we’d got a clear signal from users that they’re needed. But the time to build some of these networks is longer than users are prepared to give in terms of lead times. We’re working with Ofgem to put in place incentives to allow us to get building them now.

WindEnergyUpdate: How will you manage the variability of the wind energy produced?

Duncan Burt: The two major pieces of cross-industry work that are happening on that are the Poyry market study which has recently been completed, looking at how the energy market behaves with high wind. A lot of people are saying the prices would be very volatile and there wouldn’t be enough spare generation, so the report looked at the kind of investment and capital issues associated with that.

And then we’ve also launched this Spring our own consultation, looking at how we’ll operate the system in 2020, with large amounts of wind on it. The wind will come on gradually and therefore the developments that we do will come on gradually as well. We’ve started work on a number of the network reinforcements identified by the ENSG, particularly work on the western link is well under way.

The scale of the options and solutions we need partly depends on the amount of wind we’ve got on the system, certainly up until the levels we expect in 2020, which is around the 30GW mark. We need to make sure we’ve procured sufficient reserve plant, to make sure we can manage reserves safely on the day. This mean the using the best of what we’ve got in terms of energy storage facilities like the pump storage stations in Scotland.

It’s about using demand in a smart grid context, so we can take demand when the wind is blowing. We ‘re looking at a number of different aspects of that, for example, if we see increased levels of electric cars, there could well be options to control the charging of those cars such that they’re only taking power when the wind blows. We’re also looking at aggregating demand on the system, such as refrigeration, so that we can turn appliances off when the wind stops blowing, and back on an hour or two later to help manage those short term intermittent blips. 

WindEnergyUpdate: Are connection waiting times for wind decreasing or increasing?

Duncan Burt: Waiting times for wind are definitely decreasing at the moment. We’ve been working very hard over the last 18 months on getting rid of the queues for transmission access, particularly in Scotland for renewables. As so far we’ve invited 1.3 GW of mainly renewables in Scotland to come forward and connect earlier. Historically we’ve had connection dates up to 2018. But we’ve now offered these dates all prior to 2014.

WindEnergyUpdate: How have you managed to reduce the connection times?

Duncan Burt: By looking at different ways that we can operate the system. The key development has been between ourselves and Ofgem a development of interim connect and manage, which has come out of our access proposals. It’s a framework whereby we connect people and then manage the system very closely ahead of all the transmissions reinforcements. In some cases it will give rise to transmission constraints where we’ll pay people to reduce their output. In most cases it’s more likely that we’ll be reducing a gas fired or coal fired plant rather than wind.

We put in place a commercial framework with Ofgem, which has allowed us to increase the costs of operating the system, to allow people to connect ahead of the reinforcements being done. We incur a bit more cost in the short term in terms of constraints but it means these projects can move forward to connect to the system. The issue of who’s going to pay for it is being debated at the moment. DECC are consulting on the final proposals for transmission access. The favoured option is hybrid connect and manage, which is where the connecting party would pick up some of the additional costs, and the rest of the costs would be picked up by the general charge which fall on all users of the system. The money it costs to reduce connection waiting times in the short term is in the tens of millions.

In the medium term the right answer is that we put in additional network capacity that will remove the constraints on the system and remove those ongoing costs. The ongoing costs might be five million in the first year, ten million in the second year, 15 million in the third year. Gradually over time we will increase the capacity of the links to Scotland, when that comes onstream in 2012, that will increase the capacity by around 50%. We always incur a certain level of costs in operating the system so ongoing costs won’t disappear completely but they will reduce back down.

WindEnergyUpdate: What does national grid have planned regarding updating the grid to incorporate renewable energy over the next five years?

Duncan Burt: Over the next five years, the amount of wind on the system is likely to be such that the fluctuations don’t become very challenging to manage. We can handle the capacities we can expect over the next five years using many of our existing tools. We’ll be refining some of the technology development and looking at how we can operate the system so that we can implement it from 2015 through to 2020. That’s what all the cross industry work at the moment is driving at. The short-term concern for us in the next five years is getting wind farms connected and as system operators we have a big role to play in that.