As the Chair of the Office for Renewable Energy Deployment, I’ve been following with interest the recent blog posts by the Guardian and the Global Warming Policy Foundation who take opposing views on the viability of wind turbines as part of the UK’s energy mix.
So what is our view at DECC?
We know that the carbon intensity of electricity generation, at any point on any given day, depends on a range of factors. Not only whether the wind is blowing but also on the power flows between Great Britain and its neighbours, the shape of the demand curve on that day, whether any big power plants are out for maintenance, and various other factors.
Given this, we do not think it is meaningful to take short snapshots of time and extrapolate them forwards into the future, and use that to draw overall conclusions – but that is what the GWPF report tries to do.
The report argues that each MW of wind generating capacity has to be backed up by approximately one MW of generating plant. But this is not strictly correct as any backup plant would be needed anyway to cover other fluctuations such as surges in demand - for example, a major TV event such as England taking part in a World Cup penalty shootout could cause a demand spike of around two to three GW, which would need to be backed up.
So we need to think about the whole system and wind plays a key role in that. For example, Sizewell B nuclear power plant was out of commission for seven months in 2010 and during that time, wind was producing the electricity for hundreds of thousands of homes.
Wind is a cost-effective technology that is helping us meet our energy security objectives in a low carbon way. As wind is a free resource, the only costs reside in the manufacture, construction and maintenance of the infrastructure. For example for onshore wind, the energy used during build and installation is paid back within 4-6 months of operation. And electricity generated from wind power has one of the lowest carbon footprints, compared with other forms of generation.
We accept that some older power stations nearing the end of their life are being used as system back up - but this includes covering demand spikes and other station outages, as well as wind generation, and would be the case whether wind generation were connected or not. Several of these older power plants will close over the next few years as emissions legislation results in their owners deciding to close them, rather than invest more in the mitigation of emissions.
Furthermore, recent announcements make clear that a number of coal fired power stations will convert to biomass in the next few years. This means that, to the extent backup for variable renewables is required, much of it will come from low carbon generation such as biomass.
We know that the transition to a cleaner overall generation mix will take a period of years and it is important to ensure that during the course of this transition we do not set perverse incentives. That is why we are drawing on the data we have available from National Grid and other industry players, to inform our market design decisions as we finalise the operational details of our Electricity Market Reform (EMR) programme.
Our current and potential future interconnection with Denmark, Ireland and Norway, makes use of their renewable power and studies in Denmark have shown that Danish and UK wind speeds are generally unconnected, thereby providing good back up.
It is our vision that the power system post-2020 should look very different to what we see today. In the long run, EMR will aim to create the market conditions where the capacity to back up wind is provided by a mixture of newer, more efficient power plants, interconnection and demand response and storage.
If these ambitions are realised, wind could provide a viable, sustainable alternative, powering the country and helping the UK meet its decarbonisation targets.