Ed Conway: 'Plausible theory' reliance on solar and wind played part in power outages chaos Were the power outages something to do with sustainable power sources? Ed Conway, Sky News's economics and data editor, says it is a "plausible theory". He explained: "When you are massively reliant on things like solar and wind and you don't have that much gas-powered generation going on, then it does potentially leave you more vulnerable to things like this happening. "There's something called inertia in the system. "Basically, when you've got lots of generators turning at a certain rpm (revolutions per minute) it means there's the ability of a big power grid to deal with sudden falls." He added: "When you have a lot of solar - when you don't have a lot of those things turning - then you're much more vulnerable. "And that’s the scary thing - is the system more vulnerable to it [when there is a lot of wind and solar]. "The theory would say it is." For context: Spain is one of Europe's biggest producers of renewable energy. Data from Red Electrica, the partly state-owned Spanish energy producer, shows solar photovoltaic (PV) energy was providing almost 59% of Spain's electricity at the time of the blackout, while wind power was providing nearly 12%, nuclear power almost 11% and combined cycle gas plants 5%.