Wind turbines and solar panels are a waste of money if Britain wants reliable low carbon electricity supplies through the winter, the late Professor Sir David MacKay said in his final interview.
Prof MacKay, who served as chief scientific advisor to the Department of Energy and Climate Change for five years until 2014, died from cancer last month.
In an interview with the science writer Mark Lynas, filmed 11 days before his death and released posthumously, Prof Mackay said the “sensible thing” for the UK to do was to focus on nuclear and on carbon capture and storage technology, which traps the emissions from power stations.
He criticised the “appalling delusion” that renewable sources of power could simply be scaled up and paired with battery storage to provide all the UK’s energy needs, citing the high costs and large areas of land that would be required.
Prof MacKay was renowned in the energy world for his bookSustainable Energy – Without the Hot Air, which examined the potential limitations of renewable power, but said he had “always tried to avoid advocating particular solutions”.
However in his final interview – in which he stressed he would be “content with any plan that adds up” – he set out for the first time his own recommendation for “the rational thing to do in the UK”, explaining: “Maybe [as] the time is getting thinner, I should call a spade a spade.”
“For the UK, I think we want a zero carbon solution and it has to work in the winter,” he said.
The British public also seemed to care about the cost of energy, he said, so “we should be looking for a low carbon solution that is low cost”.
Prof MacKay said: “If you just cost-optimise and say it has to keep working in the winter, even if there’s no wind for seven days at time and obviously no sun… the sensible thing to do for a country like the UK, I think, is to focus on carbon capture and storage (CCS), which the world needs anyway, and nuclear.
“Then if you ask, what is the optimal amount of wind and solar to add in as well? The answer is going to be almost zero.”
Prof MacKay said he loved wind turbines, describing them as “the cathedrals of the modern age”, but said that if the country managed to build enough low-carbon supplies to get it through periods of no wind or sun in winter, then there was “actually no point in having any wind or solar”.
Wind turbines were a “waste of money” in that scenario since “when the wind blows you are going to have to either turn those wind turbines down or something else down that you have already paid for like the nukes or the CCS”, he said.
While advocates of renewable technologies often cite the potential for electricity storage to deal with their intermittency, Prof MacKay said that balancing wind-based power supplies would require “hundreds of flooded valleys” for hydroelectric storage.
Powering the UK from solely solar and batteries would require “absurdly large” batteries, while the cost of battery technology would need to come down “by a factor of 100” for it to be a realistic option, he said.
He alleged that solar panels had been subsidised in the UK against the advice of civil servants, due to their popularity with MPs and the work of solar lobbyists.
However, Prof MacKay emphasised that the best energy solutions would vary from country to country depending on their demands and political priorities.
Solar panels were a “really good idea” in hot countries where solar power supplies correlated with times of high demand, he said, while a combination of wind and storage might make sense in a country where “price doesn’t matter”.